taxonID	type	description	language	source
1D03E8542C4DCE29FC23C5939A6CFD63.taxon	type_taxon	Type species. Lophoplax bicristata Tesch, 1918, by original designation. Gender of genus feminine. Included species. Lophoplax bicristata Tesch, 1918; L. takakurai Sakai, 1935 a.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C4DCE29FC23C5939A6CFD63.taxon	diagnosis	Diagnosis. Carapace subquadrate; only protogastric and intestinal areoles visible; epigastric region gently convex, smooth but setose, not areolate; cardiac region raised but not areolate, granulate and setose; hepatic areole absent, with only tubercle present; intestinal region forming small areole, adjacent areas slightly raised, granulate and setose, no visible intestino-branchial areole; surface adjacent to posterior carapace margin gently concave, not raised, not forming ridge, no transverse channel visible; orbit clearly visible in dorsal view, supraorbital margin breaking general carapace outline, forming distinct concavity; eyes freely movable, ocular peduncle relatively long; lateral lobe of frontal margin low, indistinct; anterolateral margin with 4 teeth (including external orbital tooth), with 2 tubercles on posterolateral margin; posterolateral margins gently converging towards posterior carapace margin. Endostome not obliquely recessed posteriorly into buccal cavern, subparallel to adjacent pterygostomial surface, low, short endostomial ridges present. Posterior margin of epistome with distinct median lobe, separated from lateral lobes by distinct fissure. Third maxilliped ischium subquadrate, length about 1.2 × width. Adult male chelipeds slightly asymmetrical; dorsal surface of carpus with quadrate areole with raised margins; chela relatively enlarged with external median surface smooth. Ambulatory legs elongate, slender, P 4 longest, about 1.8 × carapace width; merus without obvious crest on extensor margin, instead P 2 – 4 lined with low, broad well-spaced setose prominences or low tooth; P 5 extensor margin smooth, outer surface smooth, without medio-longitudinal swelling; P 4 merus length about 5 × height, distinctly longer than half carapace width. G 1 sinuous, relatively stout, tip strongly recurved.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C4DCE29FC23C5939A6CFD63.taxon	discussion	Remarks. Lophoplax sensu stricto is distinct in its carapace ornamentation and the length and slenderness of the ambulatory legs. Lophoplax is separable from Myopilumnus and Hosekia, new genus, in the following characters: the hepatic surface of the carapace is ornamented only with a tubercle (Fig. 2 A) (versus with a large, prominent areole; cf. Figs. 6 A, 7 C, D); the intestino-branchial areole is absent with only a low intestinal areole visible (Fig. 2 A) (versus intestino-branchial areole large and distinct; cf. Figs. 6 A, 7 C, D); the surface adjacent to the posterior carapace margin is relatively wide, not forming a channel as no intestino-branchial areole is present (Fig. 2 A) (versus with distinct channel between intestino-branchial areole and posterior carapace margin; cf. Figs. 6 A, 7 C, D); and the absence of a dorsal crest on the ambulatory merus (Figs. 2 A, B, 3 C, D) (versus with prominent crest; cf. Ng & Rahayu, 2023: fig. 7 G – L). The adult male chela is relatively more enlarged, with the external median surface almost smooth (Fig. 2 C, D) (versus chelae not enlarged and the outer surface of the chela densely covered with granules; cf. Fig. 6 F). The ambulatory legs are also comparatively slender (P 4 merus length about 5 × height) and more elongated (P 4 length about 1.8 × carapace width), with the merus surface lacking a medio-longitudinal swelling or ridge (Figs. 2 A, 3 C, D) (versus median part swollen, P 4 merus length 3.0 – 3.5 × height; cf. Ng & Rahayu, 2023: fig. 7 G – L). Lophoplax, like Myopilumnus, further differs from Hosekia, in having four instead of three anterolateral carapace teeth (Figs. 6 A, 7 C, D versus Figs. 1 A, 2 A). Lophoplax superficially resembles Striacoeloma, new genus, in the slender ambulatory legs (albeit with P 4 merus length about 5 × height, versus 4 × height) and in having blunt prominences along most of the lateral margins of the carapace, but is immediately distinguished by the position of the orbits: on the anterior margin and fully visible dorsally in Lophoplax, versus submarginal and scarcely visible dorsally in Striacoeloma (resembling the condition in Cryptocoeloma Miers, 1884). Serène & Soh (1976: 4, 21) recorded a small male specimen of “? Lophoplax takakurai ” from the Andaman Sea stating only that “ Like takakurai the present specimen has no elevation, but it differs by its anterolateral teeth much less clearly separated one from the other ”. On this basis, it seems unlikely to be Myopilumnus andamanicus, which was also described from the Andaman Sea (Deb, 1989; see also Trivedi et al., 2022). Serène & Soh’s (1976) record was subsequently repeated in the checklists of the Thai fauna by Naiyanetr (1980, 1998, 2007) and Ng & Davie (2002); it requires confirmation.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C4FCE2CFC7BC2B39BEDFEA3.taxon	description	(Figs. 2, 3)	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C4FCE2CFC7BC2B39BEDFEA3.taxon	materials_examined	Material examined. Lectotype (here designated): RMNH-ZMA D 103002, male (5.8 × 4.3 mm), 2.3 miles from north point of Nuhu Jaan, northwest of Kei Islands, Indonesia, 5 ° 36.5 ′ S 132 ° 55.2 ′ E, 90 m, Siboga Expedition station 260, coll. M. Weber, 16 – 18 December 1899. Paralectotype (here designated): RMNH-ZMA D 103001, male (4.5 × 3.7 mm), Borneo Bank, Strait of Makassar, Indonesia, 59 m, Siboga Expedition station 77, coll. coll. M. Weber, 10 June 1899.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C4FCE2CFC7BC2B39BEDFEA3.taxon	diagnosis	Diagnosis. Carapace frontal margin almost straight, granulate, not distinctly produced anteriorly, lateral lobe very low but just visible (Fig. 2 A, B); epigastric areole low but visible; protogastric areolet distinct, smooth (Fig. 2 A, B); metabranchial region with prominent raised granules (Fig. 2 A); median lobe on posterior margin of epistome obtusely triangular (Fig. 3 B). Distal margin of ischium of third maxilliped smooth (Fig. 3 A). Cheliped carpus dorsal surface with subquadrate areole with crenulate ridged margins (Fig. 2 A – C); proximal basal part of male chela almost smooth or with very low tubercles (Fig. 2 D). P 2 – 4 merus extensor margin distinctly crenulated, with low lobes. P 5 merus unarmed (Fig. 3 C, D). Male thoracic sternum anteriorly relatively wide (Fig. 2 E). G 1 gently sinuous, distal strongly recurved (Fig. 3 F – I). G 2 about ¼ length of G 1.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C4FCE2CFC7BC2B39BEDFEA3.taxon	description	Description. Carapace subquadrate; frontal and anterolateral margins with scattered tufts of short and long setae, not brush-like, not concealing margins; regions well demarcated with few areoles distinct: protogastric areole transversely ovate, distinct; epigastric region low, visible when denuded, not areolate; hepatic region with 1 tubercle, no areole visible; cardiac region raised, covered with granules, setose, not areolate, lateral parts with raised patches of granules, but no visible cardio-branchial areole; gastro-cardiac region depressed, with grooves visible but not deep (Fig. 1 A, B); intestinal region convex, forming rounded areole, adjacent surfaces gently raised, with small granules, setose, separated from cristate posterior carapace margin by wide space, no obvious channel (Fig. 1 A, B); meso- and metabranchial regions each with 1 gently raised area covered with granules; metabranchial region with tubercle just posterior to raised patch of granules (Fig. 1 A). Subhepatic and suborbital regions slightly rugose to almost smooth; pterygostomial region with small granules. Frontal margin weakly bilobed, almost straight, with shallow median concavity, margins granulate; lateral lobe, small, low, just visible in dorsal view (Fig. 1 A). Supraorbital margin short, sinuous, with distinct submedian lobe, without fissure or cleft (Fig. 1 A). Orbit dorsal, supraorbital margin, eyes clearly visible in dorsal view; eyes freely movable, ocular peduncle relatively long, filling orbit (Fig. 1 A). Anterolateral margin with 4 small, sharp teeth (including external orbital tooth), external orbital tooth broader, next 3 teeth acutely triangular, tip slightly enlarged (Fig. 2 A, B). Posterolateral margin uneven, with 2 tubercles, each with smaller basal granules; margins gently converging towards posterior carapace margin (Fig. 1 A). Antennules rectangular, relatively large; antennules folding laterally. Basal antennal article subquadrate; flagellum entering orbital hiatus. Epistome with median lobe of posterior margin obtusely triangular, no obvious fissure in frontal view; lateral parts sinuous with small cleft (Fig. 3 B). Endostome distinct, sloping gradually posteriorly into buccal cavern, endostomial ridges low, short. Third maxilliped with ischium relatively short, subquadrate, length 1.2 × width, with shallow median oblique sulcus; merus subquadrate, anterolateral angle gently auriculiform. Exopod relatively stout, tip reaching to just before distal edge of merus (Fig. 3 A). Male thoracic sternum surface relatively smooth, slightly rugose; sternites 1 and 2 completely fused, wide, lateral margins gently concave; sternites 3 and 4 fused with only very shallow median groove and lateral notches visible; suture between sternites 2 and 3 almost straight (Fig. 2 E). Sternite 8 clearly visible as subrectangular plate adjacent to pleonal somite 2 when pleon closed (Fig. 3 E). Tubercle of male pleonal locking mechanism on anterior third of thoracic somite 5. Adult male chelipeds almost symmetrical, stout (Fig. 1 A, B). Basis-ischium fused but suture visible; extensor margins uneven but unarmed (Fig. 1 C). Merus short, surface slightly rugose; flexor and extensor margins with tubercles and granules; inner distal angle dentiform with subdistal angle tuberculate (Fig. 1 C). Carpus surface granulate; dorsal surface with subquadrate areole with crenulate ridged margins; inner distal angle with low sharp tooth (Fig. 1 A – C). Chela with dorsal surface covered with granules; inner surface almost smooth; median and ventral surfaces almost smooth or with very low tubercles; margins of chela with scattered long and short setae, not dense or brush-like; fingers relatively slender, slightly shorter than palm, pigmented brown along distal half; occlusal margins with low teeth, forming small gape when closed (Fig. 1 C, D). Ambulatory legs long, P 4 longest, about 1.8 × carapace width; P 4 merus length about 5 × height, distinctly longer than half carapace width; outer surface slightly rugose to almost smooth; coxa rounded; merus elongate, P 2 – 4 extensor margin not cristate with low, broad, well-spaced setose prominences, P 5 merus extensor margin smooth, fully setose; surface of P 2 – 5 gently convex, without median swelling or ridge; P 2 – 5 carpus relatively smooth, with very low submarginal ridge, lowest in P 5; propodus laterally flattened, unarmed, relatively long in P 2 – 4, shortest in P 5; P 2 – 4 dactylus falciform, unarmed, P 5 dactylus shorter, slightly upturned; dactylo-propodal lock visible (Figs. 2 A, 3 C, D). Male pleon triangular, all somites and telson free; somite 1 broadly rectangular, reaching base of P 5 coxae; somite 2 transversely much narrower than somite 1, trapezoidal; somite 3 broadly subtrapezoidal, widest, somites 4 – 6 trapezoidal, gradually decreasing in width with somite 6 almost rectangular; telson slightly wider than long, rounded, slightly narrowly distally, lateral margins convex, longer than somite 6 (Fig. 3 E). G 1 relatively stout, gently sinuous, distally tapering to narrowly rounded tip, strongly hooked inwards; subdistal surface with 2 long stout setae (Fig. 3 F – I). G 2 sigmoid, about ¼ length of G 1 (Fig. 3 J). Females not known. Remarks. Lophoplax bicristata is only known from two males collected from relatively near each other (Kei Islands and Borneo Bank, Indonesia). Both are mature and were covered with silt and mud, suggesting they live on soft substrates. They were collected from depths of 59 – 90 m.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C4ACE22FC0AC1739CF3F98B.taxon	description	(Figs. 4, 5)	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C4ACE22FC0AC1739CF3F98B.taxon	materials_examined	Material examined. 1 male (5.0 × 4.2 mm) (NSMT-Cr S 1254), Futami Bay, Chichi-jima [= Island], Ogasawara Islands, Japan, 27 ° 04.77 ′ N 142 ° 11.68 ′ E to 27 ° 04.76 ′ N 142 ° 11.73 ′ E, 42.2 – 41.6 m, R / V Koyo, 2010 cruise, station KY- 10 - 25, 9 July 2010.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C4ACE22FC0AC1739CF3F98B.taxon	diagnosis	Diagnosis. Carapace frontal margin gently convex, smooth, produced anteriorly, lateral lobe not visible (Fig. 4 A, B); epigastric areole barely visible; protogastric lobe low, with granular surface (Fig. 4 B); metabranchial region with low granules (Fig. 4 B); median lobe on posterior margin of epistome subtruncate in form (Figs. 4 E, 5 E). Distal margin of ischium of third maxilliped with row of closely set low granules (Fig. 4 C). P 2 – 5 merus extensor margin P 2 – 5 with low proximal tooth (Fig. 5 F, G). Cheliped carpus dorsal surface with longitudinal areole separated by groove from swollen lateral margin (Fig. 4 A, I); proximal basal part of male chela covered with strong tubercles (Fig. 4 G). Male thoracic sternum anteriorly relatively narrower (Fig. 4 F). G 1 strongly sinuous, distal part of G 1 gently recurved (Fig. 5 I, J). G 2 sigmoid, about ¼ length of G 1.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C4ACE22FC0AC1739CF3F98B.taxon	discussion	Remarks. Lophoplax takakurai was described on the basis of a female (11.0 × 9.0 mm) collected off Yoshihama, west of Sagami Bay, and later reported from off Mikawa Bay (south of Nagoya) (Sakai, 1935 a, b, 1976). Takeda (1993) subsequently recorded the species from Shibushi Bay in Kagoshima, with Takeda & Komatsu (2018, 2023) recording it from the Ogasawara Islands. The whereabouts of the type specimen is not known but appears to be lost. The present specimen matches the type description and figures of Sakai (1935 a, 1939, 1976) well, especially in the general carapace features and proportions of the ambulatory legs. Significantly, Sakai (1935 a: text-fig. 15 c; present Fig. 5 B) figured the third maxilliped showing a row of closely set granules on the distal margin of the ischium, a character also distinct in the present male specimen (Fig. 4 C). As such, we are confident of its identity. For the moment, L. takakurai, as defined by Takeda & Komatsu (2018) and the present study, is clearly recognisable, so a neotype designation does not appear to be necessary. Although L. takakurai differs markedly from L. bicristata in many characters of the carapace and pereopods, both species have generally similar carapace shape and features. In addition, both species have a stouter G 1 (Figs. 3 F – I, 5 I, J) compared to more typical pilumnids. It is therefore reasonable to retain both species in Lophoplax for the time being. Lophoplax takakurai occurs on muddy bottoms 41.6 – 100 m in depth (Sakai, 1976; Takeda & Komatsu, 2018).	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C44CE23FEF7C6AB9C41FBE3.taxon	type_taxon	Type species. Myopilumnus andamanicus Deb, 1989 by monotypy. Gender of genus masculine. Included species. Myopilumnus andamanicus Deb, 1989; M. pannosus (Ng & Rahayu, 2023), new combination; M. sculptus (Stimpson, 1858), new combination; M. sordidus (Ng & Rahayu, 2023), new combination; M. vermiculatus (A. Milne-Edwards, 1873), new combination.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C44CE23FEF7C6AB9C41FBE3.taxon	diagnosis	Diagnosis. Carapace subhexagonal; epigastric, protogastric, hepatic, cardio-branchial and intestino-branchial areoles prominent, smooth, glabrous; posterior carapace margin cristate, adjacent to transversely narrow but prominent intestino-branchial areole forming transverse channel extending to sub-branchial region; orbit clearly visible in dorsal view, supraorbital margin breaking general carapace outline, forming distinct concavity; eyes freely movable, ocular peduncle relatively long; lateral lobe of frontal margin not visible; anterolateral margin with 4 distinct teeth or lobes (including external orbital tooth), with additional lobe or small tubercle posteriorly; posterolateral margins distinctly converging towards posterior carapace margin. Epistome with median lobe of posterior margin obtusely triangular. Endostome not obliquely recessed posteriorly into buccal cavern, subparallel to adjacent pterygostomial surface, endostomial ridges short. Third maxilliped ischium subrectangular, length about 1.4 × width. Adult male chelipeds symmetrical or almost so, not enlarged; dorsal surface of carpus with 2 – 4 ovate areoles; outer surface of chela densely covered with granules and setae. Ambulatory legs short, P 4 longest, length about 1.3 × carapace width; merus wide, stout, extensor margin cristate, outer surface with medio-longitudinal swelling or ridge; P 4 merus length about 3.0 – 3.5 × height, about half carapace width. G 1 relatively stout, tip strongly recurved.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C44CE23FEF7C6AB9C41FBE3.taxon	discussion	Remarks. The recognition of this group of species at the genus level requires the reinstatement of the name Myopilumnus Deb, 1989. Deb (1989) established the genus for one new species, M. andamanicus Deb, 1989, from the Andaman Sea. Trivedi et al. (2022) redescribed the species, known only from one female, and showed that it was morphologically closest to L. sculpta Stimpson, 1858. As such, they placed M. andamanicus in Lophoplax, thereby also synonymising Myopilumnus under it. As concluded herein, L. sculpta and its allied species differ markedly from L. bicristata Tesch, 1918, the type species of Lophoplax, requiring the recognition of Myopilumnus as a valid genus. All of the species herein assigned to Myopilumnus were figured and redescribed (as species of Lophoplax) by Trivedi et al. (2022) and Ng & Rahayu (2023).	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C45CE23FE8AC4339B6AFC20.taxon	type_taxon	Type species. Pseudocryptocoeloma symmetrinuda Edmondson, 1951, by present designation. Gender of genus feminine. Included species. Only Hosekia symmetrinuda (Edmondson, 1951).	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C45CE23FE8AC4339B6AFC20.taxon	diagnosis	Diagnosis. Carapace transversely ovate-subhexagonal; epigastric, protogastric, hepatic, cardiac and intestinal areoles glabrous, prominent, smooth; intestino-branchial areole large, transversely ovate; posterior carapace margin cristate, adjacent to large intestino-branchial areole forming transverse groove extending to edge but not reaching sub-branchial region; orbit clearly visible in dorsal view, supraorbital margin breaking general carapace outline, forming distinct concavity; eyes freely movable; ocular peduncle relatively long; lateral lobe of frontal margin not visible; anterolateral margin with 3 distinct teeth or lobes (including external orbital tooth), without additional lobe or small tubercle posteriorly; without lobe or tubercle at junction between antero- and posterolateral margins; posterolateral margins distinctly converging towards posterior carapace margin. Epistome with median lobe of posterior margin obtusely triangular. Endostome not obliquely recessed posteriorly into buccal cavern, subparallel to adjacent pterygostomial surface; endostomial ridges short. Third maxilliped ischium short, quadrate, length 1.2 × width. Adult male chelipeds symmetrical or almost so, stout, outer surface of chela densely covered with granules. Ambulatory legs short, P 4 longest, about 1.2 × carapace width; merus wide, stout, extensor margin bluntly rounded, surface without medio-longitudinal swelling; P 4 merus length about 2.2 – 2.4 × height, less than half carapace width. G 1 strongly sinuous, distally gently curved outwards, not hooked.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C45CE23FE8AC4339B6AFC20.taxon	etymology	Etymology. The name is derived from the Japanese word “ hoseki ” for jewel. Marumura & Takeda (2012: fig. 2 A) and Maenosono (2019: fig. 8 B) figured the beautiful bright red jewel-like epigastric, protogastric, and hepatic areoles of the type species, to which the genus name alludes. The gender of the genus is feminine.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C45CE23FE8AC4339B6AFC20.taxon	discussion	Remarks. Ng & Rahayu (2023: 430) argued that among the species of Lophoplax, L. symmetrinuda was distinctive and in a group of its own because of its transversely ovate carapace, large expansive areoles, low anterolateral teeth, and smooth posterolateral margin. Our re-examination of the material reinforces their suspicions, and confirms that the species should be referred to its own genus.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C45CE26FC93C3F39D57F943.taxon	description	(Figs. 6, 7)	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C45CE26FC93C3F39D57F943.taxon	materials_examined	Material examined. Holotype: BPBM 5109, male (6.5 × 5.0 mm), Siufaga, Tau, Samoa, low tide, table reef, coll. W. Harris, 1937. Others: RUMF-ZC- 5199, 1 male (7.6 × 4.2 mm), Bise, Motobu, Okinawa, Ryukyus, Japan, coll. T. Maenosono, 10 February 2016; RUMF-ZC- 7536, 1 female (9.7 × 6.9 mm), Odo Beach, Itoman, Okinawa, Ryukyus, Japan, coll. T. Maenosono, 7 April 2020.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C45CE26FC93C3F39D57F943.taxon	diagnosis	Diagnosis. As for genus.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C45CE26FC93C3F39D57F943.taxon	description	Description. Carapace transversely ovate-subhexagonal; frontal and anterolateral margins with scattered tufts of short and long setae, not brush-like, not concealing margins; regions well demarcated with areoles smooth, prominent: epigastric areoles distinct; protogastric areole well developed, extending obliquely to branchial region, approximately separated by median constriction; cardio-branchial areole transversely ovate, well-developed; gastro-cardiac region depressed, with grooves barely visible (Figs. 6 A, B, 7 A, C, D); intestino-branchial areoles prominent, transversely ovate, one on each side of low intestinal region; posterior carapace margin cristate, adjacent to prominent intestino-branchial areole, forming narrow channel extending to beginning of sub-branchial region; no ridges on sub-branchial region (Figs. 6 A, B, 7 A, C, D). Subhepatic and suborbital regions slightly rugose to almost smooth; pterygostomial region with numerous closely packed small granules (Fig. 6 C – E). Frontal margin bilobed, gently convex, with narrow, small median notch, without lateral lobe (Figs. 6 A – D, 7 C, D). Supraorbital margin short, sinuous, with low lobe on posterior half (formed by anterior margin of hepatic areole), without fissure or cleft (Figs. 6 A, 7 C, D). Orbit dorsal, supraorbital margin appears confluent with general carapace outline, eyes clearly visible in dorsal view; eyes mobile, ocular peduncle short, filling orbit (Fig. 6 B – D). Anterolateral margin with 3 distinct teeth (including external orbital tooth), first 2 broadly triangular with cristate margin, last tooth lower, more rounded; distinct groove visible adjacent to margin, formed with outer margin of hepatic lobe (Figs. 6 A, 7 C, D). Posterolateral margin gently convex, smooth, unarmed; margins distinctly converging towards posterior carapace margin (Figs. 6 A, 7 C, D). Antennules rectangular, relatively large; antennules folding laterally (Fig. 6 C, D). Basal antennal article subquadrate; flagellum enters orbital hiatus (Fig. 6 C, D). Epistome with biconcave posterior margin, median lobe triangular with very short median fissue (Fig. 6 C, D). Endostome distinct, sloping gradually posteriorly into buccal cavern, endostomial ridges, short, low (Fig. 6 C, D). Third maxilliped with ischium relatively short, subquadrate, length 1.2 × width; merus quadrate, anterolateral angle gently auriculiform. Exopod relatively stout, tip reaching to just before distal edge of merus (Figs. 6 D, E, 7 B). Male thoracic sternum surface relatively smooth; sternites 1 and 2 completely fused, lateral margins gently concave; sternites 3 and 4 fused with only very shallow median groove and lateral notches visible; suture between sternites 2 and 3 gently concave towards buccal cavity (Figs. 6 D, E, 7 E). Tubercle of male pleonal locking mechanism on anterior third of somite 5 (Fig. 6 E). Adult male chelipeds symmetrical, stout (Fig. 7 A). Basis-ischium fused but suture visible, flexor margin with low granules (Fig. 7 E). Merus short, surface slightly rugose; flexor and extensor margins with small granules; inner distal angle sharp visible but not with subdistal angle not elongate (Fig. 7 E). Carpus surface granulate; inner distal angle with low sharp tooth (Fig. 7 A). Chela with dorsal surface densely covered with granules; inner surface almost smooth; margins of chela with scattered long and short setae, not dense or brush-like; fingers relatively slender, shorter than palm, pigmented brown along distal ⅔; occlusal margins with low teeth, forming small gape when closed (Fig. 6 F). Ambulatory legs short, P 4 longest, about 1.2 × carapace width; P 4 merus length about 2.2 – 2.4 × height, less than half carapace width; outer surface slightly rugose to almost smooth; coxa rounded; merus short, extensor margin not cristate, surface of P 2 – 5 gently convex, without ridge; P 2 – 5 carpus smooth, with low submarginal ridge, lowest in P 5; propodus laterally flattened, unarmed, relatively short in P 2 – 4, shortest in P 5; P 2 – 4 dactylus falciform, unarmed, P 5 dactylus shorter, tip slightly upturned; dactylo-propodal lock distinct (Fig. 7 A). Male pleon triangular, all somites and telson free; somite 1 broadly rectangular, reaching base of P 5 coxae; somite 2 transversely narrower than somite 1, trapezoidal; somites 3 – 6 trapezoidal, gradually decreasing in width. Telson wider than long, rounded-subtriangular, lateral margins weakly convex, longer than somite 6 (Fig. 7 E). G 1 strongly sinuous, distally gently curved outwards, tip mucronate; with short row of setae subdistally. G 2 sigmoid, about ¼ length of G 1. Female pleon longitudinally ovate; with 6 somites and telson, all free; not completely covering thoracic sternum; somite 1 broadly subrectangular, just reaching base of P 5 coxae; somite 2 transversely narrower than somite 1, trapezoidal; somite 3 widest, somite 4 as wide as somite 2; somites 3 – 6 trapezoidal, gradually decreasing in width; telson triangular with convex lateral margins, longer than somite 6. Sternopleonal cavity shallow (Fig. 7 F; vulva large, obliquely ovate, covering anterior ⅔ on sternite 6, without vulvar projections (Fig. 7 F).	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C45CE26FC93C3F39D57F943.taxon	discussion	Remarks. Hosekia symmetrinuda is a reef species currently known only from Samoa and southern Japan. The specimens from both locations are nearly identical and we are confident they are conspecific. Nothing else is known about its biology except that it occurs in the intertidal zone (Maenosono, 2019).	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C40CE27FE89C6D39FC8FD80.taxon	type_taxon	Type species. Lophoplax sextuberculata Takeda & Kurata, 1984, by present designation. Gender of genus feminine. Included species. Only Lophoplax sextuberculata Takeda & Kurata, 1984.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C40CE27FE89C6D39FC8FD80.taxon	diagnosis	Diagnosis. Carapace rectangular; epigastric, postorbital and hepatic areoles well developed with anterior margin cristate to subcristate; epigastric region gently convex, smooth, setose, not areolate; protogastric, cardiac, mesobranchial and cardiobranchial regions may be raised to form areole in larger specimens, barely or not visible in smaller specimens; intestinal region not prominently raised, no visible intestino-branchial areole; surface adjacent to posterior carapace margin almost flat, not forming ridge, no transverse channel visible; orbit clearly visible in dorsal view, supraorbital margin breaking general carapace outline, forming distinct concavity; eyes freely movable, ocular peduncle relatively long; lateral lobe of frontal margin low, indistinct; anterolateral margin with 4 visible teeth or spines (including external orbital tooth), last one often small; posterolateral margins sinuous, gently converging towards posterior carapace margin. Endostome not obliquely recessed posteriorly into buccal cavern, subparallel to adjacent pterygostomial surface, low, short endostomial ridges. Posterior margin of epistome entire, without lateral fissures, median part triangular, lateral parts distinctly concave. Third maxilliped ischium subquadrate, length about 1.3 × width. Adult male chelipeds almost symmetrical; dorsal surface of carpus with prominent longitudinal areole, separated from swollen lateral fringe by groove; chela relatively slender with external surface covered with tubercles and granules. Ambulatory legs elongate, slender, P 4 longest, about 2.0 × carapace width; P 2 – 5 merus without crest on extensor margin, distally unarmed, outer surface smooth, without medio-longitudinal swelling; P 4 merus length about 4.3 × height, distinctly longer than half carapace width. G 1 strongly sinuous, tip recurved.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C40CE27FE89C6D39FC8FD80.taxon	etymology	Etymology. The genus is named after Masatsune Takeda, whose work on the genus has been invaluable in the present revision, and we thank him for encouraging us to “ finish the job ” by revising the generic position of all species previously placed in Lophoplax. The name is derived from his family name, in arbitrary combination with Lophoplax. Gender is feminine.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C40CE27FE89C6D39FC8FD80.taxon	discussion	Remarks. The six prominent areolets on the anterior half of the carapace of Lophoplax sextuberculata is the only character that links the species to Lophoplax, although the position of the areolets are different. Compared to Lophoplax sensu stricto, however, L. sextuberculata has a distinctly wider carapace which appears rectangular in form, in sharp contrast to the more quadrate form. Most markedly, it differs in having the posterior margin of the epistome entire, without any lateral fissures (Figs. 8 E, 9 D). In Lophoplax sensu stricto, as well as Myopilumnus, Hosekia, new genus, and Striacoeloma, new genus, the posterior epistomial margin is divided into three distinct lobes by well-defined fissures (e. g., Figs. 3 B, 4 E, 5 E, 6 C, D). The form of the epistome is the same as in the pilumnid genus Pseudolitochira Ward, 1942 (sensu Ng et al., 2021). Species of Pseudolitochira, however, are very setose, with long silky setae that partially or completely obscure the margins and surfaces, and lack any trace of areoles on the carapace, with the regions smooth and hardly demarcated (Ng & Clark, 2022 a, b; Ng & Lin, 2023; Ng, 2024 a). In the general appearance of the carapace, especially in the overall shape and the reduced size of the fourth anterolateral tooth / spine, Lophoplax sextuberculata is superficially similar to Viaderiana typica Ward, 1942, the type species of Viaderiana Ward, 1942. Viaderiana typica (and congeners), however, have the extensor margin of the ambulatory merus armed with at least one spine, the regions are never prominently raised to form granules, the ischium of the third maxilliped is distinctly more elongate, and the posterior epistomal margin is divided into three distinct lobes by distinct fissures (see Ng, 2023, 2024 b). As such, Lophoplax sextuberculata is made the type species of Takedaplax, new genus.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C41CE3AFF4AC2939D57FE63.taxon	description	(Figs. 8, 9)	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C41CE3AFF4AC2939D57FE63.taxon	materials_examined	Material examined. 1 male (4.0 × 3.2 mm) (NSMT-Cr S 1253), west of Chichi-jima [= Island], Ogasawara Islands, Japan, 27 ° 04.55 ′ N 142 ° 09.16 ′ E – 27 ° 04.73 ′ N 142 ° 09.31 ′ E, 83 – 81 m, R / V Koyo, 2008 cruise, station KY- 08 - 15, 28 October 2008.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C41CE3AFF4AC2939D57FE63.taxon	diagnosis	Diagnosis. As for genus.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C41CE3AFF4AC2939D57FE63.taxon	description	Description. Carapace rectangular; frontal and anterolateral margins with scattered tufts of short and medium-length setae, not brush-like, not concealing margins; regions well demarcated with 6 anterior areoles always large, distinct: epigastric areole with cristate anterior margin; postorbital areole transversely wide, anterior margin subcristate; hepatic areole rounded with subcristate anterior margin; protogastric, cardiac, mesobranchial and cardiobranchial regions gently convex to barely discernible in smaller specimens, gently raised to low areoles in larger specimens; gastro-cardiac with grooves shallow (Fig. 8 A, B); intestinal region not prominently raised, no visible intestino-branchial areole; surface adjacent to posterior carapace margin almost flat, not forming ridge, no transverse channel visible (Fig. 8 B); mesobranchial regions smooth; metabranchial regions covered with granules (Fig. 8 B). Subhepatic and suborbital regions almost smooth; pterygostomial region with scattered small granules (Fig. 8 D). Frontal margin distinctly bilobed, convex, with deep median cleft, lateral lobe very low, just visible in dorsal view (Fig. 8 A, B). Supraorbital margin long, sinuous, with distinct submedian lobe, without fissure or cleft (Fig. 8 B). Orbit dorsal, supraorbital margin, eyes clearly visible in dorsal view; eyes freely movable, ocular peduncle relatively long, filling orbit (Fig. 8 B, D). Anterolateral margin with 4 visible teeth or spines (including external orbital tooth), external orbital tooth triangular, next 3 teeth acutely triangular to spiniform, last tooth smallest (Fig. 8 A, B). Posterolateral margin sinuous, unarmed, margins gently converging towards almost straight posterior carapace margin (Fig. 8 A, B). Antennules rectangular, relatively large; antennules folding laterally (Fig. 8 D). Basal antennal article subquadrate; flagellum entering orbital hiatus. Posterior margin of epistome entire, without lateral fissures, median part triangular, lateral parts distinctly concave (8 E, 9 D). Endostome not obliquely recessed posteriorly into buccal cavern, subparallel to adjacent pterygostomial surface, low, short endostomial ridges present. Third maxilliped with ischium relatively short, subquadrate, length 1.3 × width, with shallow median oblique sulcus; merus subquadrate, anterolateral angle slightly auriculiform. Exopod relatively stout, tip just reaching to before distal edge of merus (Figs. 8 C, 9 C). Male thoracic sternum surface smooth; sternites 1 and 2 completely fused, wide, lateral margins gently concave to sinuous; sternites 3 and 4 fused with only very shallow median groove and lateral notches visible; suture between sternites 2 and 3 gently sinuous (Fig. 8 F). Sternite 8 clearly visible as subovate plate adjacent to pleonal somite 2 when pleon closed (Fig. 9 G). Tubercle of male pleonal locking mechanism on anterior one-third of somite 5. Adult male chelipeds almost symmetrical, relatively slender (Fig. 8 A, G, H). Basis-ischium fused but suture visible; extensor margins granulated (Fig. 1 C). Merus short, surface slightly rugose; flexor and extensor margins with tubercles and granules; inner distal angle dentiform with low subdistal angle (Fig. 8 A, H). Carpus surface granulate; dorsal surface of carpus with prominent longitudinal areole, separated from swollen lateral fringe by groove; inner distal angle with sharp tooth (Figs. 8 A, H, 9 B). Chela with dorsal surface covered with granules; inner surface almost smooth; median and ventral surfaces covered with tubercles and granules; margins of chela with scattered long and short setae, not dense or brush-like; fingers slender, slightly shorter than palm, pigmented brown along distal half; occlusal margins with low teeth, forming distinct gape when closed (Fig. 8 G, H). Ambulatory legs long, P 4 longest, about 2.0 × carapace width; P 4 merus length about 4.3 × height, distinctly longer than half carapace width; outer surface almost smooth; coxa rounded; merus elongate, P 2 – 5 extensor margin not armed, entire, lined with short and long setae that does not obscure surface; surface of P 2 – 5 gently convex, without median swelling or ridge; P 2 – 5 carpus relatively smooth, with very low submarginal ridge, lowest or barely visible in P 5; propodus laterally flattened, unarmed, relatively long in P 2 – 4, shortest in P 5; P 2 – 4 dactylus falciform, unarmed, P 5 dactylus shorter, slightly upturned; dactylo-propodal lock visible (Figs. 8 A, 9 E, F). Male pleon triangular, all somites and telson free; somite 1 broadly rectangular, reaching base of P 5 coxae; somite 2 transversely narrower than somite 1, subtrapezoidal; somite 3 broadly subtrapezoidal, as wide as somite 1, somites 4 and 5 trapezoidal, somite 6 and telson missing (Fig. 9 G). G 1 strongly sinuous, distally recurved, tapering to slightly rounded tip, hooked inwards; subdistal surface with 1 long stout seta (Fig. 9 H, I). G 2 short, about ¼ length of G 1, sigmoid (Fig. 9 J).	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C41CE3AFF4AC2939D57FE63.taxon	discussion	Remarks. Lophoplax sextuberculata was described from the female holotype (8.2 × 6.2 mm) and two male paratypes (both 5.2 × 3.8 mm) collected from inside a fish stomach from Takinoura Bay, Ani-jima [= Island], Ogasawara Islands, and a paratype male (5.5 × 4.5 mm) from Tanegashima [= Island] (southern Kyushu) (Takeda & Kurata, 1984; Takeda, 1993). Takeda & Marumura (1995) reported additional specimens from the Kii Peninsula and Ryukyus. They noted that while the median and posterior surfaces of the carapace were smooth in the type specimens from the Ogasawara Islands (as in the case of the present specimen; see also Takeda & Komatsu, 2018: fig. 6 H); the specimens from Tanegashima [= Island] and Kii Peninsula had seven additional areoles in two transverse rows on the following regions: two on the protogastric, one each on anterior parts of the mesobranchials, one cardiac and one each on the cardiobranchials (see Takeda & Marumura, 1995: 89, 91, fig. 1). They noted that the only specimen they had from the Ryukyus was small (4.8 × 4.0 mm) and had the median and posterior parts of the carapace smooth (Takeda & Marumura, 1995: 91). As such, Takeda & Marumura (1995: 91) observed that “ … there may be some individual differences as for the development of the areolets on the posterior part, but it is concluded that Lophoplax sextuberculata is characterised by having 13 areolets, not 6 mentioned in the original description and scientific name ”. Examining the present specimen from the Ogasawara Islands, we note that its protogastric, mesobranchial, cardiac, and cardiobranchial regions are only gently convex and smooth, and barely discernible as areolets in dorsal view (Fig. 8 A, B, D). In the colour figure of this specimen (Takeda & Komatsu, 2018: fig. 6 H), we note that these regions are also slightly more orangish than the surrounding beige surface as described by Takeda & Marumura (1995) for their specimens. As such, it seems likely that these areolets are present but not always discernible, probably becoming more prominent in larger individuals. Ng & Rahayu (2023) reported a similar situation for Myopilumnus sordidus and M. vermiculatus, where the areoles are relatively poorly developed in young specimens.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C5CCE3AFEF1C1B39A31FB83.taxon	type_taxon	Type species. Striacoeloma tubur, new species, by present designation. Gender of genus neuter. Included species. Only Striacoeloma tubur, new species.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C5CCE3AFEF1C1B39A31FB83.taxon	diagnosis	Diagnosis. Carapace subhexagonal; frontal and anterolateral margins with scattered tufts of short and long setae, not brush-like; surface appearing irregularly transversely corrugated, partly eroded; gastric and cardiac regions prominently raised, forming transverse swellings extending to branchial region, almost to lateral margin; surface adjacent to posterior carapace margin raised, with prominent wide rounded transverse ridge adjacent to the posterior carapace margin, forming channel extending to sub-branchial region; orbit submarginal, supraorbital margin almost confluent with general carapace outline, eyes only partially visible in dorsal view; eyes scarcely movable, ocular peduncle short, filling orbit, scarcely movable; lateral lobe of frontal margin small but distinct; anterolateral margin with 4 distinct teeth (including external orbital tooth), first 2 broad, lobiform, with 2 additional tubercles on posterolateral margin; posterolateral margins distinctly converging towards posterior carapace margin. Epistome with shallow biconcave posterior margin, median lobe subtruncate. Endostome short, recessed posteriorly into buccal cavern oblique to plane of adjacent pterygostomial surface, endostomial ridges low, short. Third maxilliped ischium short, quadrate, length 1.2 × width; merus with anterolateral angle distinctly auriculiform. Adult female chelipeds symmetrical or almost so, stout, outer surface of chela with margins rugose and covered with granules, median part smoother; margins not lined with dense brush-like setae. Ambulatory legs short, P 4 longest, about 1.3 × carapace width; merus slender, length about 4 × height, extensor margin not cristate, with evenly, widely spaced row of blunt, prominent nodules, outer surface slightly raised medio-longitudinally; P 4 merus length about 4 × height, length half carapace width.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C5CCE3AFEF1C1B39A31FB83.taxon	etymology	Etymology. The name is an arbitrary combination of the Latin word “ stria ”, for ridge, in arbitrary combination with part of the genus name, Cryptocoeloma, in recognition of the ridged carapace surface and close relationship to the pilumnid genus. Gender is feminine.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C5CCE3AFEF1C1B39A31FB83.taxon	discussion	Remarks. Whereas Striacoeloma, new genus, is superficially similar to various planopilumnids (now in the Pseudozioidea Alcock, 1898) (cf. Ng, 2010), it is clearly a pilumnid based the form of its carapace and chelipeds. The new genus is morphologically more similar to Cryptocoeloma Miers, 1884 than Lophoplax, Myopilumnus, or Hosekia, new genus. In Striacoeloma, like Cryptocoeloma, the orbits are submarginal, so the supraorbital margin does not form a strong concavity that noticeably breaks the general carapace outline. The eyes too, are relatively smaller in Striacoeloma and scarcely movable, compared with the proportionally larger, freely movable eyes of Lophoplax, Myopilumnus, and Hosekia. The chelae of Striacoeloma and Cryptocoeloma are also stouter than in Lophoplax and allies, and both have a shallow biconcave posterior margin of the epistome with the median lobe broader and subtruncate (Fig. 10 D) (versus median lobe broadly triangular; Ng et al., 2022: fig. 3 F). Striacoeloma, however, differs from Cryptocoeloma in having the dorsal surface of carapace ornamented with transverse, corrugated swellings (Fig. 10 A – C) (versus surface granulate and rugose but without swellings and regions well demarcated; Ng et al., 2022: fig. 2); the frontal and anterolateral margins have tufts of short and long setae but not dense or brush-like (Fig. 10 A, B) (versus margins evenly lined with dense short and long setae, appearing brush-like; Ng et al., 2022: figs. 1 A, B, 2 A, B, 5 A, B, 7 A, B); the outer surface of the chelae are covered with scattered long and short setae, not dense or brush-like (Fig. 10 A) (versus lined with dense brush-like setae; Ng et al., 2022: figs. 1 A, B, 2 A, B, 5 A, B, 7 A, B); the ischium of the third maxilliped is subquadrate and shorter (Fig. 10 E) (length 1.2 × width versus 1.3 ×; Ng et al., 2022: fig. 4 A); and the ambulatory merus is dentate along the extensor margin (Fig. 11 D) (versus smooth; Ng et al., 2022: figs. 2, 4 B); and the vulva is proportionately larger, occupying most of the space of sternite 5 (Fig. 11 B) (versus vulva smaller, occupying two-thirds the space of sternite 5; Ng et al., 2022: fig. 7 E, F).	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C5CCE39FC07C4939E8AFD03.taxon	description	(Figs. 10, 11)	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C5CCE39FC07C4939E8AFD03.taxon	materials_examined	Material examined. Holotype: AM P 107758, female (8.6 × 6.3 mm), Middle Arm, Darwin Harbour, Northern Territory, Australia, 12 ° 35 ′ 17 ″ S 130 ° 52 ′ 17 ″ E, 5 – 7 m, coll. Cardno Pty Ltd.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C5CCE39FC07C4939E8AFD03.taxon	etymology	Etymology. Named tubur for the tubercle-like protrusions on the extensor margins of the ambulatory legs; used as a noun in apposition.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C5CCE39FC07C4939E8AFD03.taxon	diagnosis	Diagnosis. As for genus.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C5CCE39FC07C4939E8AFD03.taxon	description	Description of holotype female. Carapace subhexagonal; frontal and anterolateral margins with scattered tufts of short and long setae, not brush-like; surface appearing irregularly corrugated, partly eroded; gastric regions prominently raised, forming 2 transverse swellings extending to branchial region, with posterior one reaching to lateral margin; gastro-cardiac region depressed, with grooves visible; cardiac region with transverse swelling, extends almost to posterolateral margin (Fig. 10 A – C); surface adjacent to posterior carapace margin raised, with prominent wide rounded transverse ridge adjacent to the posterior carapace margin, forming channel extending to sub-branchial region (Fig. 10 A, B). Subhepatic and suborbital regions slightly rugose; pterygostomial region with numerous fine granules (Fig. 10 D). Frontal margin bilobed, almost straight, lined with granules, with shallow median notch, lateral lobe small but distinct, not visible in dorsal view (Fig. 10 A – D). Supraorbital margin sinuous, with low lobe on posterior third, with 2 short fissures (Fig. 10 B, C). Orbit submarginal, supraorbital margin appearing almost confluent with general carapace outline, eyes partially visible in dorsal view; eyes scarcely movable, ocular peduncle short, filling orbit, scarcely movable (Fig. 10 C, D). Anterolateral margin with 4 distinct teeth (including external orbital tooth), first 2 broad, lobiform, with surface adjacent to them eroded, each with median oblique depression; last 2 dentiform (Fig. 10 A, B). Posterolateral margin with 2 distinct tubercles, margins distinctly converging towards posterior carapace margin (Fig. 10 A, B). Antennules rectangular, relatively large; antennules folding laterally (Fig. 10 D). Basal antennal article subquadrate; flagellum entering orbital hiatus (Fig. 10 D). Epistome with shallow biconcave posterior margin, median lobe subtruncate with short median fissue (Fig. 10 D). Endostome short, recessed posteriorly into buccal cavern oblique to plane of adjacent pterygostomial surface, endostomial ridges low, short. Third maxilliped ischium short, quadrate, length 1.2 × width; merus with anteroexternal angle distinctly auriculiform; exopod stout, tip reaching distal edge of merus (Fig. 10 E). Thoracic sternum surface smooth; sternites 1 and 2 completely fused, lateral margins sinuous; sternites 3 and 4 fused with only lateral notches demarcating sternites; suture between sternites 2 and 3 almost straight (Fig. 11 A). Adult chelipeds symmetrical or almost so, not enlarged (Fig. 10 A). Basis-ischium fused but suture visible, flexor margin with short sharp granules (Fig. 11 A). Merus short, surface rugose; flexor and extensor margins with low sharp tubercles and granules; inner distal angle sharp but not elongate, with subdistal tooth (Figs. 10 A, 11 A). Carpus rugose; inner distal angle with strong sharp tooth (Fig. 10 A). Chela with dorsal surface rugose and covered with granules, median part smoother; ventral surface near pollex covered with small granules; inner surface smooth; margins of chela with scattered long and short setae, not dense or brush-like; fingers relatively slender, shorter than palm, pigmented brown along distal ⅔; occlusal margins with low teeth, forming small gape when closed (Figs. 10 A, 11 C). Ambulatory legs relatively short, P 4 longest, about 1.3 × carapace width; outer surface gently rugose; coxa with distal angle slightly raised, no visible serrated flange; P 2 – 4 with outer surface slightly raised medio-longitudinally, indistinct on P 5; merus relatively slender, extensor margin not cristate, with evenly, widely spaced row of blunt, prominent nonsetose nodules; P 4 merus length about 4 × height, length half carapace width; P 2 – 4 carpus with outer submarginal ridge, absent on P 5; propodus laterally flattened, elongate in P 2 – 4, short in P 5; P 2 – 4 dactylus falciform, unarmed, P 5 dactylus shorter, gently upturned; dactylo-propodal lock visible (Figs. 10 A, 11 D). Female pleon longitudinally ovate; with 6 somites and telson, all free; not completely covering thoracic sternum; somite 1 broadly rectangular, just reaches base of P 5 coxae; somite 2 transversely narrower than somite 1, trapezoidal; somites 3 – 6 trapezoidal, gradually decreasing in width, somite 6 longest; telson semicircular with convex lateral margins, distinctly longer than somite 6 (Fig. 11 A). Sternopleonal cavity shallow (Fig. 11 B); vulva large, obliquely ovate, covering most of space on sternite 6, without vulvar projections (Fig. 11 B). Male. Not known.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
1D03E8542C5CCE39FC07C4939E8AFD03.taxon	discussion	Remarks. Striacoeloma tubur, new genus and species, is currently known only from the female holotype. Nothing is known about the ecology other than it was collected from soft, muddy substrates. The carapace and pereopods were partially encrusted with what appear to be light-brown, possibly ferric, precipitates, suggestive of reducing or anoxic environs.	en	Ng, Peter K. L., Ahyong,, Shane T. (2024): Redefining Lophoplax Tesch, 1918: recognising Myopilumnus Deb, 1989, and the establishment of three new genera, Hosekia, Takedaplax, and Striacoeloma (Crustacea: Brachyura: Pilumnidae). Raffles Bulletin of Zoology 72: 335-355, DOI: 10.26107/RBZ-2024-0027
