Salmoneus cristatus (Coutière, 1897), RS

Ashrafi, Hossein, Anker, Arthur & Ďuriš, Zdeněk, 2023, Revision of (Coutière, 1897) and Allied Forms (Decapoda: Caridea: Alpheidae)., Zoological Studies 62 (53), pp. 1-31 : 5-23

Salmoneus cristatus (Coutière, 1897) ( Figs. 2–5 )

Jousseaumea cristata Coutière 1897a: 234 ; Coutière 1899: 70, figs. 22, 23.

Salmoneus cristatus — Holthuis 1958: 18, fig. 7; (?) Bruce 1976: 44; Banner and Banner 1981: 54, fig. 6: Banner and Banner 1983: 88 (part.).

Not Salmoneus cristatus — Banner and Banner 1983: 88 [= S. chadwickae Ďuriš and Horká, 2016 or S. auroculatus Anker and Marin, 2006 , see below].

Not Salmoneus cristatus — Anker 2003: 108, fig. 6 [possibly = S. franseni sp. nov., see below].

Not Salmoneus cristatus — Wang and Sha 2016: 1586, figs. 1–4 [= S. paracristatus sp. nov., see below]

Not Salmoneus cristatus — Sha, Wang, and Cui 2019: 206, figs 2.121 –2.124 [= S. paracristatus sp. nov., see below]

Not Salmoneus cristatus — Banner and Banner 1966: 40, fig. 10 [possibly = S. paracristatus sp. nov., see below].

Material examined: Neotype: ovig. specimen (cl 2.5 mm), FLMNH UF 36069 , Red Sea , Saudi Arabia, off Thuwal, Shib Nazar East, 22°19'19.94"N, 38°51'17.99"E, coral reef, depth 0 20 m, coll. A. Anker et al., 16.03.2016 (BDJRS-2832) . Additional material: 1 non-ovig. specimen (cl 2.9 mm), FLMNH UF 68811, Red Sea, Saudi Arabia, north of Rabigh, 22°55'32.17"N, 38°51'21.45"E, back reef, shallow lagoon with sand and coral rubble, in coral rubble crevices, hand and hammer, depth 1 m, coll. A. Anker et al., 23.06.2022 (AA-22- 140); 1 ovig. specimen (cl 3.5 mm), RMNH. CRUS. D.14354, Red Sea, Gulf of Aqaba, Israel, 03.12.1955, coll. H. Steinitz; 1 ovig. specimen (cl 3.3 mm), MNHN- IU-2019-3851, Persian Gulf, Iran, Abu-Musa Island, Qadir Park, sandy/rocky bottom with corals, shallow subtidal (depth less than 2 m), 17.07.2019, coll. H. Ashrafi; 1 ovig. specimen (cl 3.2 mm), MNHN- IU-2019-3852, same data as for previous specimen; 1 ovig. specimen (cl 4.4 mm), MNHN-IU-2021-9769, Madagascar, Toliara (Tuléar), probably around 1977– 1979, coll. M. Peyrot-Clausade.

Redescription: Small-sized alpheid shrimps (cl range 2.5–4.4 mm). Carapace ( Fig. 3A–C ) covered by short setae, with prominent mid-dorsal carina reaching to about distal fourth of carapace; frontal region entirely concealing eyes in dorsal view, distinctly elevated from anterolateral portion of carapace, shoulder-like; rostrum triangular in dorsal view, with subacute tip, reaching to about distal margin of second antennular article, approximately as long as broad; rostral carina prominent, continued by mid-dorsal carina on carapace; orbital teeth small, subacute, reaching to proximal third of first antennular article, distinctly longer than wide; anterolateral suture present, pterygostomial angle broadly rounded, cardiac notch deep.

Pleon ( Fig. 3E ) covered with short setae; pleura of first to forth pleonites rounded anteroventrally and posteroventrally; fifth pleuron subrounded posteroventrally; sixth pleuron with subtriangular projection flanking each side of telson, posteroventral suture incomplete.

Telson ( Fig. 3D ) subrectangular, tapering distally, about 4.5 times as long as distal width, covered by scattered short setae; dorsal surface with two pairs of spiniform setae located at about 0.5 and 0.8 telson length, respectively; posterior margin with broadly U-shaped, central notch furnished with 4 plumose setae, and two pairs of spiniform setae, mesial ones about 1.6 times as long as lateral ones and about 4 times as long as spiniform setae on dorsal surface.

Antennule ( Fig. 3B, C ) with peduncle relatively stout; first article approximately as long as broad; stylocerite robust, with blunt tip, reaching to or slightly overreaching second article; second article about 0.8 times as long as broad; third article about 1.2 times as long as second article; lateral antennular flagellum biramous, fused portion with two subdivisions, shorter ramus well developed, reaching to about sixth subdivision of longer ramus, with six or so groups of aesthetascs.

Antenna ( Fig. 3B, C ) with stout basicerite, its distoventral margin armed with subacute tooth and blunt subdistal projection, superior margin projecting as small subacute tooth; scaphocerite reaching to about middle of third article of antennular peduncle, lateral tooth slightly overreaching blade; carpocerite almost reaching distal margin of second article of antennular peduncle; flagellum not particularly stout, with second subdivision distinctly longer than others.

Third maxilliped ( Fig. 5A, B ) with coxa bearing strap-like epipod and broadly rounded lateral plate; antepenultimate article slender, about six times as long as broadest part; penultimate article relatively short, about 0.5 times as long as antepenultimate article; ultimate article about twice as long as penultimate article, distally armed with small, subapical, spiniform seta; exopod slender, reaching to about distal margin of antepenultimate article; arthrobranch normally developed.

First pereiopods (chelipeds) ( Fig. 4 ) very different in size and shape. Major cheliped ( Fig. 4A–D ) robust, carried flexed under body when not in use; coxa with strap-like epipod and setobranch; ischium slender, four times as long as wide, unarmed ventrally; merus widening distally, about 2.3 times as long as ischium, with slightly concave ventral margin; carpus small, cupshaped; chela enlarged, swollen, as long as combination of basis to carpus; palm robust, about twice as long as wide, subcylindrical, slightly flattened dorsally and with shallow depression mid-dorsally and deep complex groove proximally, about 1.4 times as long as fingers; fingers relatively slender, slightly twisted, with strongly crossing fingertips, not gaping when closed; pollex with cutting edge armed with about 15 teeth, proximal fourth of cutting edge concave and with eight small teeth, distal three-fourths of cutting edge straight and with seven teeth enlarging towards distal margin; dactylus with deep depression on proximal third part of mesial surface accommodating convex margin of opposed margin of pollex, with 11 teeth on cutting edge enlarging in size towards distal margin. Minor cheliped ( Fig. 4E, F ) significantly smaller and weaker than major cheliped; coxa with strap-like epipod and setobranch; ischium slender, about four times as long as broad, unarmed ventrally; merus slender, slightly longer than ischium; carpus slightly shorter than merus, widening distally; chela simple, with palm approximately as long as fingers; cutting edges of fingers unarmed.

Second pereiopod ( Fig. 5C ) moderately long, short, slender; coxa with strap-like epipod and setobranch; ischium about 6.5 times as long as wide, unarmed ventrally; merus slender, slightly longer than ischium; carpus 1.2 times as long as merus, with five subdivisions, proximal one as long as sum of others; chela about 0.3 times as long as carpus, palm and fingers subequal in length.

Third pereiopod ( Fig. 5D ) moderately slender; coxa with strap-like epipod and setobranch; ischium slightly widening distally, about 2.6 times as long as wide, with small spiniform seta on ventrolateral surface; merus slightly inflated, about 1.6 times as long as ischium; carpus slenderer and slightly shorter than merus, eight times as long as wide, with small spiniform seta on distoventral margin; propodus slightly shorter than carpus, ventral margin armed with two spiniform setae in addition to distal pair of spiniform setae flanking dactylar base; dactylus simple, moderately slender, slightly curved, about half as long as propodus. Fourth pereiopod ( Fig. 5E ) generally similar to third one, somewhat more slender; ischium unarmed ventrally; propodus with one spiniform seta on ventral margin and one distal pair of spiniform setae adjacent to dactylus. Fifth pereiopod ( Fig. 5F ) similar to fourth pereiopod in length; coxa without strap-like epipod, with setobranch; carpus as long as merus, unarmed; propodus about 1.3 times as long as carpus, bearing seven rows of microserrulate setae on distoventral margin and two spiniform setae on ventral margin in addition to distal pair.

Uropods ( Fig. 3D, E ) with lateral lobe of protopod elongate, subacute distally; exopod ovate, distolateral margin with small triangular tooth adjacent to stout spiniform seta, diaeresis sinuous, with blunt lobe mesial to spiniform seta; endopod slightly longer than exopod, slender, ovoid, without specific features.

Colour in life: Background translucent whitish; carapace with several bright red bands disposed as following: one narrow, longitudinal band along anterior half of mid-dorsal carina; two narrow, oblique-transverse bands, one on each anterolateral surface, extending from just below each eye towards pterygostomial region; and moderately broad, transverse band across posterior one-fifth of carapace continued by narrower oblique band on each flank; pleon with six transverse, moderately broad, bright red bands, one per pleonite; antennular peduncles, telson and uropods with red markings; remaining appendages colourless; major cheliped hyaline white; fresh eggs bright yellow-orange; ovaries (visible by translucence) yellow ( Fig. 2 ).

Variation: The present description is consistent for the neotype as well as Iranian material. However, one of the specimens from the Red Sea ( FLMNH UF 68811) differs from the others in the armature of the ischium of the minor cheliped and that of the second pereiopod. In this specimen, each of these articles is armed with a small spiniform seta on the ventrolateral surface, contrasting to the unarmed ischia in the other specimens examined. Since the colour pattern of this specimen does not differ from that of the neotype or the Iranian specimen ( Fig. 2 ) and since it is also genetically not different from the neotype ( Fig. 1 ), there is no doubt that it represents S. cristatus .

Type locality: Djibouti (Coutière 1897).

Distribution: Red Sea (Coutière 1897 1899; locality not specified), including Gulf of Suez, Egypt ( Banner and Banner 1981), Gulf of Aqaba, Israel ( Holthuis 1958), and central coast of Saudi Arabia: Thuwal reefs and Rabigh (present study); Gulf of Aden: Djibouti ( Coutière 1897a 1899; Banner and Banner 1981); Persian Gulf: Abu Musa Island, Iran (present study); Kenya: Malindi ( Bruce 1976; Banner and Banner 1983); Madagascar: Toliara ( Banner and Banner 1983); and Seychelles: Mahé ( Banner and Banner 1983).

Remarks: The originally designated type specimen(s) of S. cristatus in Coutière (1897) could not be found in the MNHN collection neither by Banner and Banner (1981) nor by the present authors, and therefore, should be considered as non-extant. The topotypic specimen of S. cristatus collected by Ch. Gravier in Djibouti and illustrated by Banner and Banner (1981) (deposited under MNHN Na-2781) was also not located in the MNHN collection, despite several search attempts by the authors (HA, AA, pers. obs.). However, it must be noted that it is unlikely that this apparently lost specimen represented the original type (or one of the types) of S. cristatus in Coutière (1897). Since the herein reported material from the Red Sea fully aligns with Coutière’s (1897 1899) descriptions and illustrations, as well as with the topotypic specimen examined by Banner and Banner (1981), one of the specimens from Saudi Arabia ( FLMNH UF 36069) is designated as neotype for S. cristatus .

The ovigerous specimen from the Gulf of Aqaba reported by Holthuis (1958) ( RMNH. CRUS.D.14354) is missing its major cheliped and therefore cannot be confirmed as S. cristatus , although nothing in its overall morphology (carapace, telson, third pereiopod, etc.) indicates the contrary. The original lot from Toliara (Tuléar), Madagascar, (MNHN-IU-2021-9769), which was reported by Banner and Banner (1983) under S. cristatus , contained three specimens. However, during our re-examination of this lot, only two specimens were found, and both lack all their pereiopods. One specimen appears to be S. cristatus , based on the general shape of the frontal region. However, the frontal region of the second specimen (separated under MNHN- IU-2021-9770 as S. cf. chadwickae ) resembles more that of S. chadwickae or S. auroculatus .

Salmoneus paracristatus sp. nov. ( Figs. 6–9 ) urn:lsid:zoobank.org:act:B510DE87-C798-4445-977E-AD43442CEB9D

Salmoneus aff. cristatus — Ďuriš and Horká 2016: 783 (part.), fig. 11 a–c [not S. cristatus (Coutière, 1897) ].

(?) Salmoneus cristatus — Anker 2003: 108, fig. 6 [not S. cristatus (Coutière, 1897) ].

Material examined: Holotype: non-ovig. specimen (cl 2.9 mm), MNHN-IU-2014-199, Papua New Guinea, New Ireland, off Cape Nuan, Kavieng 2014 expedition, sta. KS13, 2°33'28.08"S, 150°47'25.98"E, sand with coral, depth 13 m, coll. MNHN team, 05.06.2014 . Paratypes: 1 non-ovig. specimen (cl 5.8 mm), MNHN- IU-2014-205, Papua New Guinea, New Ireland, E of North Cape, Kavieng 2014 expedition, sta. KB8, 2°33'10.02"S, 150°48'9"E, reef slope, brushing of dead corals, depth 13 m, coll. MNHN team, 05.06.2014 [infected with bopyrid isopod]; 1 non-ovig. specimen (cl 4.1 mm), MNHN-IU-2014-294, Papua New Guinea, New Ireland, between Big Nusa and Little Nusa Islands, Kavieng 2014 expedition, sta. KB16, 2°34'33.66"S, 150°46'20.88"E, oceanic front reef, brushing of dead corals, depth 13 m, coll. MNHN team, 07.06.2014.

Etymology: The new species’ name integrates the Greek-derived prefix para - for beside, near, and the adjective cristatus for crested, referring to its morphological similarity with S. cristatus .

Description: small-sized alpheid shrimps (cl range of type material 2.9–5.8 mm). Carapace ( Fig. 7A– C ) sparsely setose, with prominent mid-dorsal carina reaching to about distal fourth of carapace; frontal region entirely concealing eyes in dorsal view, distinctly elevated from anterolateral portion of carapace, shoulder-like; rostrum triangular in dorsal view, with subacute tip, tapering distally, reaching to about distal margin of second antennular article, slightly longer than broad, rostral carina prominent, continued by mid-dorsal carina on carapace; orbital teeth small, subacute, approximately as long as broad; anterolateral suture present, pterygostomial angle broadly rounded, cardiac notch deep.

Pleon ( Fig. 7D ) sparsely covered by short setae; pleura of first to fourth pleonites rounded anteroventrally and posteroventrally; fifth pleuron subrounded posteroventrally; sixth pleuron with small triangular projection flanking each side of telson, posteroventral suture incomplete.

Telson ( Fig. 7D, E ) sub-rectangular, tapering distally, about 5.2 times as long as distal width, proximal margin about 2.4 times as broad as distal margin; dorsal surface with two pairs of spiniform setae located at about 0.5 and 0.8 telson length; posterior margin with broadly U-shaped, central notch furnished with 2 plumose setae, and two pairs of spiniform setae, mesial pair slightly shorter than plumose setae, about 1.8 times as long as lateral one and about five times as long as spiniform setae on dorsal surface.

Antennule ( Fig. 7B, C ) with peduncle relatively stout; first antennular article approximately as long as broad, stylocerite relatively robust, with blunt tip, reaching to distal margin of second article; second article about 1.3 times as broad as long; third antennular article about 1.7 times as long as second one, slightly longer than broad; lateral antennular flagellum biramous, fused portion with two subdivisions, shorter ramus well-developed, reaching to about seventh subdivision of longer ramus, with 9 or so groups of aesthetascs.

Antenna ( Fig. 7B, C ) with stout basicerite, its distoventral margin armed with subacute tooth and blunt subdistal projection, superior margin projecting as small subacute tooth; scaphocerite overreaching mid-length of third antennular article, blade slightly surpassing lateral tooth; carpocerite stout, slightly overreaching second antennular article, flagellum not particularly stout, second subdivision of flagellum remarkably longer than others.

Third maxilliped ( Fig. 9A, B ) with coxa bearing strap-like epipod and broadly rounded lateral plate; antepenultimate article slender, about 7.5 times as long as proximal width; penultimate article relatively short, about 0.3 times as long as antepenultimate article; ultimate article about 2.5 times as long as penultimate article, distally armed with small, subapical, spiniform seta; exopod slender, reaching to about distal margin of antepenultimate article; arthrobranch normally developed.

First pereiopods ( Fig. 8 ) very different in size and shape. Major cheliped ( Fig. 8A–C ) robust, carried flexed under body when not in use; coxa with strap-like epipod and setobranch; ischium relatively slender, about four times as long as proximal width, unarmed ventrally; merus about 1.7 times as long as ischium, slightly widening distally; carpus vase-shaped, about 1.7 times as long as proximal width; chela enlarged, swollen, as long as sum of basis to carpus; palm robust, about 1.8 times as long as wide, subcylindrical, slightly flattened dorsally with shallow depression mid-dorsally and deep complex groove proximally, approximately as long as fingers; fingers with strongly crossing fingertips, not gapping when closed, pollex with cutting edge armed with about 11 evenly distributed teeth slightly enlarging toward distal margin, dactylus without depression on mesio-proximal side, armed with 10 evenly distributed teeth slightly enlarging towards distal margin. Minor cheliped ( Fig. 8D, E ) significantly smaller and weaker than major cheliped; coxa with strap-like epipod and setobranch; ischium slender, slightly widening distally, about four times as long as mid-width, unarmed ventrally; merus slightly swollen, slightly longer than ischium; carpus slightly longer than merus, widening distally; chela with palm approximately as long as fingers, cutting edge of fingers unarmed.

Second pereiopod ( Fig. 9C ) moderately long, slender; coxa with strap-like epipod and setobranch; ischium slender, about 8 times as long as wide, unarmed ventrally; merus slender, as long as ischium; carpus slender, 1.2 times as long as merus, with five subdivisions, proximal subdivision longest, slightly longer than sum of others, third and fourth subdivisions subequal, second subdivision slightly longer than third one, last subdivision as long as second and third ones combined, chela about 0.3 times as long as carpus, palm and fingers subequal in length.

Third pereiopod ( Fig. 9D ) moderately slender; coxa with strap-like epipod and setobranch; ischium slightly widening distally, about four times as long as widest part, with small spiniform seta on ventrolateral surface; merus slightly inflated, about 1.5 times as long as ischium; carpus slenderer and slightly shorter than merus, 6.5 times as long as distal width, with small spiniform seta on distoventral margin; propodus slender, about 1.2 times as long as carpus, ventral margin with five spiniform setae in addition to distal pair of spiniform setae flanking dactylar base; dactylus simple, moderately slender, slightly curved, about 0.4 times as long as propodus. Fourth pereiopod ( Fig. 9E ) generally similar to third one but slightly slenderer; propodus armed with four spiniform setae on ventral margin in addition to distal pair. Fifth pereiopod missing.

Uropods ( Fig. 7D ) with lateral lobe of protopod broadly triangular; exopod ovate, anterolateral margin with small triangular tooth adjacent to relatively stout spiniform seta, diaeresis sinuous; endopod slightly longer than exopod, ovoid, without specific feature.

Colour in life: Body largely translucent with fawnyellow tinge; pleon with faint, buff-yellow, transverse bands; antennular and antennal flagella pale orange; major cheliped hyaline white with orange-yellow tinge on fingers; remaining appendages colourless or with buff-yellow tinge ( Fig. 6 ).

Type locality: Papua New Guinea (present study).

Distribution: Papua New Guinea: New Ireland ( Ďuriš and Horká 2016, as S. aff. cristatus ; present study); possibly Australia: Ashmore Reef off Queensland ( Anker 2003, as S. cristatus ).

Salmoneus franseni sp. nov. ( Figs. 10–13 ) urn:lsid:zoobank.org:act:A78DCC3C-0544-44B0-A086-63040293219A

Salmoneus aff. cristatus — Ďuriš and Horká 2016: 783 (part.) [not S. cristatus (Coutière, 1897) ].

Salmoneus cristatus — Wang and Sha 2016: 1586, figs. 1–4 [not S. cristatus (Coutière, 1897) ].

Salmoneus cristatus — Sha, Wang, and Cui 2019: 206, figs 2.121 – 2.124 [not S. cristatus (Coutière, 1897) ].

(?) Salmoneus cristatus — Banner and Banner 1966: 40, fig. 10 [not S. cristatus (Coutière, 1897) ].

Material examined: Holotype: non-ovig. specimen (cl 3.2 mm), MNHN-IU-2014-881, Papua New Guinea, Kavieng 2014 expedition, sta. KB60, 2°32'30"S, 150°35'18"E, sand and coarse rubble, brushing of dead corals, depth 20 m, coll. MNHN team, 23.06.2014 . Additional material: 1 non-ovig. specimen (cl 2.7 mm), MNHN-IU-2014-933, same collection data as for holotype (see discussion below).

Etymology: The species is named after Dr. Charles H.J.M. Fransen (Naturalis Biodiversity Center, Leiden) for his major contribution to taxonomy of caridean shrimps, including description of a peculiar cave species of Salmoneus ( Fransen 1991) .

Description: Small-sized alpheid shrimps (cl 3.2 mm in holotype). Carapace ( Fig. 11A–C ) with prominent mid-dorsal carina reaching to about posterior fourth of carapace; frontal region fully concealing eyes in dorsal view, mid-dorsal carina prominent and reaching to about posterior fourth of carapace, distinctly elevated from anterolateral portion of carapace, shoulder-like; rostrum triangular in dorsal view, with subacute tip, reaching to about distal margin of second antennular article, as long as broad, rostral carina prominent, continued by mid-dorsal carina on carapace; orbital teeth small, subacute, as long as broad; anterolateral suture present, pterygostomial angle broadly rounded, cardiac notch deep.

Pleon ( Fig. 11D ) scarcely furnished with fine setae; pleura of first to third pleonites rounded anteroventrally and posteroventrally; fourth pleuron subrounded posteroventrally; fifth pleuron with small subacute projection posteroventrally; sixth pleuron with small subacute projection flanking each side of telson, posteroventral suture incomplete.

Telson ( Fig. 11D, E ) sub-rectangular, tapering distally, about 4.3 times as long as distal width, proximal margin about twice as broad as distal margin; dorsal surface with two pairs of spiniform setae located at about 0.5 and 0.8 telson length, respectively; posterior margin with broadly U-shaped, central notch furnished with two plumose setae, and two pairs of spiniform setae, mesial pair about 1.5 times as long as lateral one and about four times as long as spiniform setae on dorsal surface.

Antennule ( Fig. 11B, C ) with peduncle relatively stout; first antennular article approximately as long as broad, stylocerite relatively robust, with blunt tip, reaching to about distal margin of second article; second article about 1.6 times as broad as long; third article about 1.6 times as long as second article, slightly longer than wide; lateral antennular flagellum biramous, fused portion composed of one subdivision, shorter ramus well-developed, reaching to about ninth subdivision of longer ramus, with eight or so groups of aesthetascs.

Antenna ( Fig. 11B, C ) with stout basicerite, its distoventral margin armed with subacute tooth and blunt subdistal projection, superior margin projecting as small subacute tooth; scaphocerite reaching to about mid-length of third antennular article, blade slightly surpassing lateral tooth; carpocerite stout, slightly overreaching second antennular article.

Third maxilliped ( Fig. 13A, B ) with coxa bearing strap-like epipod and broadly rounded lateral plate; antepenultimate article slender, about nine times as long as proximal width; penultimate article relatively short, about 0.3 times as long as antepenultimate article; ultimate article about twice as long as penultimate article, distally armed with two subapical spiniform setae; exopod slender, reaching to about distal margin of antepenultimate segment; arthrobranch normally developed.

First pereiopods ( Fig. 12 ) very different in size and shape. Major cheliped ( Fig. 12A–D ) robust, carried flexed under body when not in use; coxa with strap-like epipod and setobranch; ischium relatively slender, about 4.3 times as long as proximal width, unarmed ventrally; merus slightly widening distally, about twice as long as ischium, ventral margin somehow flattened; carpus vase-shaped; chela enlarged, swollen, as long as combination of basis to carpus; palm robust, about 1.7 times as long as wide, subcylindrical, slightly flattened dorsally and with shallow depression mid-dorsally and deep complex groove proximally, approximately as long as fingers; fingers with strongly crossing fingertips, without gap when closed, with nine (dactylus) or 10 (pollex) evenly distributed teeth slightly enlarging towards distal margin; dactylus without concavity on proximal part of mesial surface. Minor cheliped ( Fig. 12E, F ) significantly smaller and weaker than major cheliped; coxa with strap-like epipod and setobranch; ischium slender, about 4.5 times as long as mid-width, unarmed ventrally; merus slightly swollen, slightly longer than ischium; carpus slightly longer than merus, widening distally; chela simple, with palm approximately as long as fingers, cutting edge of fingers unarmed.

Second pereiopod ( Fig. 13C ) slender; coxa with strap-like epipod and setobranch; ischium slender, about eight times as long as broad, unarmed ventrally; merus slender, as long as ischium; carpus slender, 1.5 times as long as merus, with five subdivisions, proximal subdivision longest, slightly longer than sum of other subdivisions, third and fourth subdivisions subequal, second subdivision slightly longer than the third, last subdivision as long as second and third subdivisions combined; chela about 0.3 times as long as carpus, palm and fingers subequal in length.

Third pereiopod ( Fig. 13D ) moderately slender; coxa with strap-like epipod and setobranch; ischium slightly widening distally, about four times as long as distal margin, unarmed ventrally; merus slightly inflated, about 1.5 times as long as ischium; carpus more slender and slightly shorter than merus, 7.5 times as long as distal width, with spiniform seta on distoventral margin; propodus slender, approximately as long as carpus, ventral margin armed with four spiniform setae in addition to distal pair flanking dactylar base; dactylus simple, moderately slender, slightly curved, about 0.5 times as long as propodus. Fourth pereiopod ( Fig. 13E ) generally similar to third one but slightly more slender; propodus 1.2 times as long as carpus, ventrally armed with three spiniform setae and one distal pair. Fifth pereiopod ( Fig. 13F ) generally similar to fourth one; coxa without strap-like epipod; carpus slightly shorter than merus; propodus about 1.3 times as long as carpus, ventrally armed with six spiniform setae and one distal pair, bearing 7 rows of microserrulate setae on distoventral margin.

Uropod ( Fig. 11D ) with lateral lobe of protopod broadly triangular; exopod ovate, distolateral margin with small triangular tooth adjacent to spiniform seta, diaeresis sinuous; endopod slightly longer than exopod, ovoid, without specific features.

Colour in life: Body largely translucent with pale yellow or pale orange tinge; pleon with faint, buff-yellow, transverse bands; antennular and antennal flagella pale yellow; major cheliped whitish with orange-yellow tinge on fingers; remaining appendages colourless or with buff-yellow tinge ( Fig. 10 ).

Type locality: Papua New Guinea (present study).

Distribution: Papua New Guinea: New Ireland ( Ďuriš and Horká 2016; present study); southern China: Xisha Islands ( Wang and Sha 2016; Sha et al. 2019 as S. cristatus ); probably also in Thailand: Phuket ( Banner and Banner 1966, as S. cristatus ).

Salmoneus alius sp. nov. ( Figs. 14–17 ) urn:lsid:zoobank.org:act:E68C3BB2-FB39-4DA9-95E1-FF54979FEB59

Material examined: Holotype: 1 non-ovig. specimen (cl 2.7 mm), MNHN-IU-2019-3495, New Caledonia, Koumac 2019 expedition, sta. HR2, Hienghène, 20°44'59.35"S, 165°16'34.86"E, reef slope, depth 10–34 m, coll. MNHN team, 09.11.2019 . Paratypes: 1 ovig. specimen (cl 3.8 mm), FLMNH- UF-60000, Solomon Islands, New Georgia, Munda, Sosu Hite Island (informal name), shallow reef flat, less than 1.5 m, under corals and coral rubble, coll. A. Anker, 20.09.2016 (SOL-035); 1 specimen (cl not measured), MNHN-IU-2013-1471, Papua New Guinea, Madang 2012 expedition, sta. PR119, Madang lagoon, northern side of North Kranket Island, 5°11'20.04"S, 145°49'27.03"E, silty reef, depth 1–10 m, coll. A. Anker & Z. Ďuriš, 28.11.2012.

Etymology: The new species name is the Latin adjective alius for another or different, referring to yet another new species described in the genus Salmoneus , adding to over 40 species described over the last two decades.

Description: Small-sized alpheid shrimp (cl 2.7 mm). Carapace ( Fig. 15A, B ) with prominent mid-dorsal carina reaching to about posterior margin of eyes, frontal region entirely concealing eyes in dorsal view, distinctly elevated from anterolateral portion of carapace, shoulder-like; rostrum triangular in dorsal view, with subacute tip, reaching to about distal margin of second antennular article, slightly broader than long, rostral carina prominent, continued by mid-dorsal carina on carapace; orbital teeth small, subacute, as long as broad; anterolateral suture present, pterygostomial angle broadly rounded, cardiac notch deep.

Pleon ( Fig. 15C ) scarcely furnished with long fine setae; pleura of first to third pleonites rounded anteroventrally and posteroventrally; fourth and fifth pleura angular posteroventrally; sixth pleuron with subtriangular projection flanking each side of telson, posteroventral suture incomplete.

Telson ( Fig. 15C, D ) sub-rectangular, slightly tapering distally, about four times as long as distal width, proximal margin about 1.6 times as broad as distal margin; dorsal surface with two pairs of spiniform setae located on 0.6 and 0.8 telson length, respectively; posterior margin with broadly U-shaped, central notch furnished with two plumose setae, and two pairs of spiniform setae, mesial pair slightly shorter than plumose setae, much thicker than lateral pair, about 1.5 times as long as lateral one, about five times as long as spiniform setae on dorsal surface.

Antennule ( Fig. 15A, B ) with peduncle relatively stout; first article approximately as long as broad, stylocerite relatively robust, with blunt tip, slightly overreaching distal margin of second antennular article; second article about 1.5 times as broad as long; third article about 1.3 times as long as second article, as long as broad; lateral antennular flagellum biramous, fused portion with two subdivisions, shorter ramus well-developed, reaching to about seventh subdivision of longer ramus, with seven or so groups of aesthetascs.

Antenna ( Fig. 15A, B ) with stout basicerite, distoventral margin with subacute tooth, superior margin projecting as small subacute tooth; scaphocerite slightly overreaching mid-length of third antennular article, blade slightly surpassing lateral tooth; carpocerite stout, slightly overreaching second antennular article, flagellum not particularly stout, with second subdivision distinctly longer than others.

Third maxilliped ( Fig. 17A, B ) with coxa bearing strap-like epipod and broadly rounded lateral plate; antepenultimate article slender, about 7.6 times as long as proximal width; penultimate article relatively short, about 0.2 times as long as antepenultimate article; ultimate article about 2.5 times as long as penultimate article, distally armed with two subapical spiniform setae; exopod slender, falling short of reaching distal margin of antepenultimate segment; arthrobranch normally developed.

First pereiopods ( Fig. 16 ) very different in size and shape. Major cheliped ( Fig. 16A D ) robust, carried flexed under body when not in use; coxa with strap-like epipod and setobranch; ischium relatively slender, about 3.3 times as long as proximal width, unarmed ventrally; merus about 1.9 times as long as ischium, slightly widening distally, ventral margin somehow flattened; carpus vase-shaped; chela enlarged, swollen, slightly shorter than combination of basis to carpus; palm robust, swollen, about 1.7 times as long as wide, subcylindrical, slightly flattened dorsally and with shallow depression mid-dorsally, with obsolete ridge on mid-lateral margin and small shallow depression on mid-ventral side of ridge, and with deep complex groove proximally, approximately as long as fingers; fingers with strongly crossing fingertips, no gapping when closed, with 10 (dactylus) or 12 (pollex) evenly distributed teeth slightly enlarging toward distal margin; dactylus without depression proximal part of mesial surface. Minor cheliped ( Fig. 16E, F ) significantly smaller and weaker than major cheliped; coxa with strap-like epipod and setobranch; ischium slender, about four times as long as mid-width, unarmed ventrally; merus slightly swollen, slightly longer than ischium; carpus slightly shorter than merus, widening distally; chela simple, with palm approximately as long as fingers; cutting edge of fingers unarmed.

Second pereiopod ( Fig. 17C ) moderately long, slender; coxa with strap-like epipod and setobranch; ischium slender, about 6.5 times as long as wide, unarmed ventrally; merus slender, slightly longer than ischium; carpus slender, 1.3 times as long as merus, with five subdivisions, proximal subdivision longest, slightly longer than sum of other subdivisions, third and fourth subdivisions subequal, second subdivision slightly longer than third one, distal subdivision as long as second and third subdivisions combined; chela about 0.4 times as long as carpus, palm and fingers subequal in length.

Third pereiopod ( Fig. 17D ) moderately slender, coxa with strap-like epipod and setobranch; ischium slightly widening distally, about three times as long as distal margin, with two strong spiniform setae on ventrolateral surface; merus slightly inflated, about 1.7 times as long as ischium; carpus slenderer and shorter than merus, 5.3 times as long as distal width, with spiniform seta on distoventral margin; propodus slender, approximately as long as carpus, with ventral margin armed with four spiniform setae in addition to distal pair of spiniform setae flanking dactylar base; dactylus simple, moderately slender, slightly curved, about 0.4 times as long as propodus. Fourth pereiopod ( Fig. 17E ) generally similar to the third, more slender somewhat; propodus 1.1 times as long as carpus, ventral margin armed with three spiniform setae and one pair distally. Fifth pereiopod ( Fig. 17F ) generally similar to fourth; coxa without strap-like epipod; ischium unarmed ventrally; carpus slightly longer than merus; propodus about 1.3 times as long as carpus, ventral margin armed with five spiniform setae and one pair distally, bearing seven rows of microserrulate setae on distoventral margin; dactylus conical, somewhat blunt distally (probably due to usage).

Uropod with lateral lobe of protopod broadly triangular; exopod ovate, distolateral margin with small triangular tooth adjacent to spiniform seta; diaeresis sinuous, with blunt lobe mesial to spiniform seta; endopod ovoid, without specific features.

Colour in life: Body largely translucent with yellow tinge; pleon with faint, yellow, transverse bands; antennular and antennal flagella pale yellow; major cheliped whitish with buff tinge on fingers; remaining appendages colourless; developing ovaries and eggs orange ( Fig. 14 ).

Type locality: New Caledonia (holotype); additional type material from Papua New Guinea and Solomon Islands (present study).

Distribution: Presently known from the northeastern coast of New Caledonia, Papua New Guinea (Kavieng), and the Solomon Islands (New Georgia).

Figures

Fig. 2. Salmoneus cristatus (Coutière, 1897), shrimps in life; A, B, ovigerous specimen (cl 3.3 mm) from Abu-Musa Island, Iran (MNHN- IU-2019-3851), in dorsal (A) and dorsolateral (B) views [photographs courtesy of Rashed Abdollahi]; C, D, neotype, ovigerous specimen (cl 2.5 mm) from Shib Nazar East reef off Thuwal, Saudi Arabia (FLMNH UF 36069), in dorsal (A) and dorsolateral (B) views [photographs by AA].

Fig. 3. Salmoneus cristatus Coutière, 1897, ovigerous specimen (cl 3.3 mm) from Abu-Musa Island, Iran (MNHN-IU-2019-3851): A, carapace, dorsal view; B, anterior region of carapace and frontal appendages, lateral view; C, same, dorsal view; D, telson and uropods, dorsal view; E, posterior pleonites, telson and right uropod, lateral view.

Fig. 4. Salmoneus cristatus Coutière, 1897, ovigerous specimen (cl 3.3 mm) from Abu-Musa Island, Iran (MNHN-IU-2019-3851): A, left (major) cheliped, lateral view; B, same, chela, lateral view; C, same, mesial view; D, same, distal half of palm and fingers open, lateral view; E, right (minor) cheliped, lateral view.

Fig. 5. Salmoneus cristatus Coutière, 1897, ovigerous specimen (cl 3.3 mm) from Abu-Musa Island, Iran (MNHN-IU-2019-3851): A, third maxilliped, lateral view; B, same, ultimate article, mesial view; C, second pereiopod, lateral view; D, third pereiopod, lateral view; E, fourth pereiopod, lateral view; F, fifth pereiopod, lateral view.

Fig. 1. Bayesian and Maximum Likelihood concatenated tree (based on 16S and COI) of selected species of Salmoneus with focus on the S. cristatus species group, showing two different clades morphologically allied to S. cristatus. Numbers above or under each branch are bootstrap supports and Bayesian posterior probabilities, respectively (supports and probabilities under 60/0.6 are not shown). Insert photographs show S. franseni sp. nov. (yellow clade) and S. cristatus (red clade). Abbreviations used: FA, French Antilles; FP, French Polynesia; PG, Persian Gulf; PH, Philippines; PNG, Papua New Guinea; RS, Red Sea; HT, holotype; NT, neotype; PT, paratype. Sequences for S. aduncus, S. auroculatus, S. chadwickae, and S. shojaei were obtained from GenBank (see Ďuriš and Horká 2016; Komai 2022; Ashrafi et al. 2022).

Fig. 6. Salmoneus paracristatus sp. nov., shrimps photographed post-mortem: A, paratype, non-ovigerous specimen (cl 5.8 mm) from New Ireland, Papua New Guinea (MNHN-IU-2014-205), in lateral view; B, paratype, non-ovigerous specimen (cl 4.1 mm) from New Ireland, Papua New Guinea (MNHN-IU-2014-294), in lateral view [photographs by ZĎ].

Fig. 7. Salmoneus paracristatus sp. nov., holotype, non-ovigerous specimen (cl 2.9 mm) from New Ireland, Papua New Guinea (MNHN- IU-2014-199): A, carapace, dorsal view; B, anterior region of carapace and frontal appendages, lateral view; C, same, dorsal view; D, posterior pleonites, telson and right uropod, lateral view; E, telson, dorsal view.

Fig. 8. Salmoneus paracristatus sp. nov., holotype, non-ovigerous specimen (cl 2.9 mm) from New Ireland, Papua New Guinea (MNHN- IU-2014-199): A, left (major) cheliped, lateral view; B, same, chela, mesial view; C, same, lateral view; D, right (minor) cheliped, lateral view; E, same, chela, mesial view.

Fig. 9. Salmoneus paracristatus sp. nov., holotype, non-ovigerous specimen (cl 2.9 mm) from New Ireland, Papua New Guinea (MNHN- IU-2014-199): A, third maxilliped, lateral view; B, same, ultimate article, mesial view; C, second pereiopod, lateral view; D, third pereiopod, lateral view; E, fourth pereiopod, lateral view.

Fig. 10. Salmoneus franseni sp. nov., holotype, non-ovigerous specimen (cl 3.2 mm) from New Ireland, Papua New Guinea (MNHN-IU-2014-881), shrimp in life in dorsolateral (A) and lateral (B) views [photographs by ZĎ].

Fig. 11. Salmoneus franseni sp. nov., holotype, non-ovigerous specimen (cl 3.2 mm) from New Ireland, Papua New Guinea (MNHN-IU-2014-881): A, carapace, dorsal view; B, anterior region of carapace and frontal appendages, lateral view; C, same, dorsal view; D, posterior pleonites, telson and left uropod, lateral view; E, telson, dorsal view.

Fig. 12. Salmoneus franseni sp. nov., holotype, non-ovigerous specimen (cl 3.2 mm) from New Ireland, Papua New Guinea (MNHN-IU-2014-881): A, right (major) cheliped, lateral view; B, same, chela, mesial view; C, same, lateral view; D, same, distal portion of palm and fingers slightly open, lateral view; E, left (minor) cheliped, lateral view; F, same, chela, mesial view.

Fig. 13. Salmoneus franseni sp. nov., holotype, non-ovigerous specimen (cl 3.2 mm) from New Ireland, Papua New Guinea (MNHN-IU-2014-881): A, third maxilliped, lateral view; B, same, ultimate article, mesial view; C, second pereiopod, lateral view; D, third pereiopod, lateral view; E, fourth pereiopod, lateral view; F, fifth pereiopod, lateral view.

Fig. 14. Salmoneus alius sp. nov., holotype, non-ovigerous specimen (cl 2.7 mm) from New Caledonia (MNHN-IU-2019-3495), shrimp in life in dorsal view (A) lateral view (B); paratype, ovigerous specimen (cl 3.8 mm) from the Solomon Islands (FLMNH-UF-60000), shrimp in life in lateral view (C). [photographs A, B by ZĎ; and C by AA].

Fig. 15. Salmoneus alius sp. nov., holotype, non-ovigerous specimen (cl 2.7 mm) from New Caledonia (MNHN-IU-2019-3495): A, anterior region of carapace and frontal appendages, lateral view; B, same, dorsal view; C, posterior pleonites, telson and left uropod, lateral view; D, telson, dorsal view.

Fig. 16. Salmoneus alius sp. nov., holotype, non-ovigerous specimen (cl 2.7 mm) from New Caledonia (MNHN-IU-2019-3495): A, right (major) cheliped, lateral view; B, same, chela, lateral view; C, same, mesial view; D, same, distal portion of palm and fingers open, lateral view; E, left (minor) cheliped, lateral view; F, same, chela, mesial view.

Fig. 17. Salmoneus alius sp. nov., holotype, non-ovigerous specimen (cl 2.7 mm) from New Caledonia (MNHN-IU-2019-3495): A, third maxilliped, lateral view; B, same, ultimate article, mesial view; C, second pereiopod, lateral view; D, third pereiopod, lateral view; E, fourth pereiopod, lateral view; F, fifth pereiopod, lateral view.