Platynereis hemeiensis, Hsueh, 2022

Hsueh, Pan-Wen, 2022, Fig. 14 in An Integrative Description of Two New Species (Tardigrada: Eutardigrada: Macrobiotidae) with Updated Genus Phylogeny., Zoological Studies 61 (30), pp. 1-13 : 2-11

Family Nereididae Blainville, 1818 Subfamily Nereidinae Blainville, 1818 Genus Platynereis Kinberg, 1865

Platynereis hemeiensis sp. nov. ( Figs. 1A–C , 2A–F , 3A–E ) urn:lsid:zoobank.org:act:05DBCFA0-D0A7-4797-B485-8BF223C3729B

Material examined: Holotype, NMNS8390-1 , Hemei (25°2.6'N 121°55.8'E), Gongliao District , New Taipei City, Taiwan, intertidal rocky habitats, coll. S.-M. Chao, 12 Mar. 1989 . Paratype: 1 specimen, NMNS 8390- 2, Longdong (25°5.1'N 121°55.2'E), Gongliao District, New Taipei City, Taiwan, intertidal rocky habitats, coll. H.- T. Hong, 3 Jun. 1996.

Etymology: The name is derived from the name of the nearby village, Hemei, in northeastern Taiwan where the holotype was collected.

Diagnosis: Platynereis with longest tentacular cirri reaching chaetiger 4. Dark brown jaws, each with 4 lateral teeth; paragnath pattern: I = 0; II = 0; III = 5 groups of pectinate paragnaths, each group with 2–3 parallel transverse rows; IV = 6–8 parallel diagonal lines of pectinate paragnaths, innermost 2–3 lines incomplete in the middle; V = 0; VI = 2 parallel transverse rows of pectinate paragnaths on each side; VII –VIII = 5 groups of pectinate paragnaths, each group with 2 parallel transverse rows. Notopodial prechaetal lobe present on anterior to mid-body chaetigers. Neuropodial postchaetal lobe present throughout. Notochaetae with homogomph spinigers throughout, without homogomph falcigers. Neurochaetae with homogomph spinigers throughout; dorsal fascicle with heterogomph spinigers on chaetigers 1–4, short-bladed heterogomph falcigers with recurved tip and serrations present throughout except chaetigers 1–4; ventral fascicle with heterogomph spinigers on chaetigers 1–4 and mid-body to posterior chaetigers, short-bladed heterogomph falcigers with recurved tip and serrations present throughout except chaetigers 1–4.

Description: Holotype complete, 39.0 mm long, 86 chaetigers, chaetiger 10 width 2.0 mm (2.5, n = 1), excluding parapodia; beige in alcohol ( Fig. 1A ). Prostomium slightly longer than wide, lateral antennae separated basally, as long as palps; palpophores globose, palpostyles half as long as palpophores, blunt, medially widest, four pairs of tentacular cirri, longest one reaching chaetiger 4. Two pairs of eyes, in trapezoidal arrangement, separated from each other, subequal in size; anterior eyes 1/7–1/8 as wide as prostomium. Tentacular belt about 1.2 times (1.5 times, n = 1) longer than chaetiger 1. Pharynx with dark brown jaws, each with 4 lateral teeth; paragnath pattern: I = 0; II = 0; III = 5 groups of pectinate paragnaths, each group with 2–3 parallel transverse rows; IV = 6–7 (7–8, n = 1) parallel diagonal lines of pectinate paragnaths, innermost 2–3 lines incomplete in the middle; V = 0; VI = 2 parallel transverse rows of pectinate paragnaths on each side; VII –VIII = 5 groups of pectinate paragnaths, each group with 2 parallel transverse rows ( Fig. 1B–C ). Ridge pattern of Areas VI – V – VI, υ-shaped ( Fig. 1A–B ).

Dorsal cirri tapered, basally attached to dorsal ligule throughout, about as long as dorsal ligule on anterior chaetigers, about 0.7–0.8 times as long as dorsal ligule on mid-body to posterior chaetigers ( Fig. 2A–F ). Notopodial prechaetal lobe present on anterior to mid-body chaetigers ( Fig. 2C, D ).

Dorsal ligule narrow conical on anterior-most chaetigers, conical from chaetiger 5 to 11 (5 to 12, n = 1), narrow conical with blunt tip on second-half portion of anterior to posterior chaetigers ( Fig. 2A–F ); base of dorsal ligule slightly bulged on anterior chaetigers, elongate and broader on mid-body chaetigers, markedly elongate and broader on posterior chaetigers ( Fig. 2A– F ); small, beige glandular patches present on anterior chaetigers, glandular patches becoming light yellow, enlarged and fused into large mass on mid-body to posterior chaetigers ( Fig. 2A–F ).

Median ligule subconical on anterior-most chaetigers, about 0.9 as long as dorsal ligule; conical from chaetiger 5 to 11 (5 to 12, n = 1), subconical with blunt tip on posterior portion of anterior to posterior chaetigers, about 0.8 times as long as dorsal ligule ( Fig. 2A–F ).

Neuroacicular ligule subconical acute on anterior chaetigers, subconical blunt tip on mid-body to posterior chaetigers, about 0.4–0.5 times as long as ventral ligule ( Fig. 2A–F ). Neuropodial postchaetal lobe present throughout, subconical on anterior-most chaetigers, about 1.8 times longer than neuroacicular ligule; conical on chaetiger 5 to 11 (5 to 12, n = 1), about 0.5 times as long as neuroacicular ligule; subconical on mid-body to posterior chaetiger, about as long as neuroacicular ligule ( Fig. 2A–F ).

Ventral ligule narrow conical on anterior-most chaetigers, conical on chaetiger 5 to 11 (5 to 12, n = 1), narrow conical on mid-body to posterior chaetigers ( Fig. 2A–F ). Ventral cirri basally attached to ventral edge of parapodia, about as long as ventral ligule on anterior-most chaetigers, about 1.5 times longer than ventral ligule on chaetiger 5 to 11 (5 to 12, n = 1), about 0.8 times as long as ventral ligule on mid-body to posterior chaetigers ( Fig. 2A–F ).

Notochaetae present from chaetiger 3 to posterior chaetigers, homogomph spinigers present throughout, homogomph falcigers absent. Neurochaetae dorsal fascicle: homogomph spinigers present throughout, heterogomph spinigers present on chaetigers 1–4, short-bladed heterogomph falcigers with recurved tip and serrations present throughout except chaetigers 1–4. Neurochaetae ventral fascicle: heterogomph spinigers present on chaetigers 1–4 and mid-body to posterior chaetigers, short-bladed heterogomph falcigers with recurved tip and serrations present throughout except chaetigers 1–4 ( Fig. 3A–E ).

Type locality: Hemei, New Taipei City, Taiwan.

Distribution: Only known from the type locality and Longdong, New Taipei City, Taiwan.

Remarks: Platynereis hemeiensis sp. nov. is similar to P. abnormis ( Horst, 1924) , P. australis (Schmarda, 1861) , P. hutchingsae de Leon-Gonzalez, Solis-Weiss & Valadez Rocha, 2001 , and P. sinica Sun, Wu and Shen, 1978 in term of lacking notopodial homogomph falcigers in adults ( Horst 1924: 164; Read 2007: 6; de Leon Gonzalez et al. 2001: 390–391; Sun and Young 2004: 220; Fig. 3 ). Of the latter four species, only P. australis has paragnath patterns somewhat similar to that of P. hemeiensis sp. nov. However, P. hemeiensis sp. nov. differs from P. australis by having fewer transverse rows or diagonal lines in Areas III, IV, VI and VII –VIII (2–3, 6–8, 2 and 2 versus 5, 10, 4 and 4, respectively), in addition to the shape of dorsal cirri on anterior-most chaetigers and the length of dorsal cirri to dorsal ligule in posterior chaetigers (see the Key) ( Read 2007: 6–7, fig. 1A–D, F; Fig. 1A–C, F ). Platynereis hemeiensis sp. nov. can be distinguished from P. abnormis and P. sinica by having parallel transverse rows of pectinate paragnaths in Area III (versus no pectinate paragnaths) ( Horst 1924: 20; Wu et al. 1981; Sun and Young 2004: 210; Fig. 1B–C ). Platynereis hemeiensis sp. nov. can be readily differentiated from P. hutchingsae by having long-bladed heterogomph spinigers (versus short-bladed heterogomph spinigers) and short-bladed heterogomph falcigers with recurved tip and serrations (versus short-bladed heterogomph falcigers without recurved tip) in dorsal fascicle of neuropodia ( de Leon Gonzalez et al. 2001: 390–391, fig. 1e, g; Fig. 3C ).

Platynereis jihueiensis sp. nov. ( Figs. 4A–F , 5A–F , 6A–F ) urn:lsid:zoobank.org:act:AE4C0ACA-A334-4674-95BA-18AEB2CD8D4F

Material examined: Holotype ( NMNS 8390- 3 ), Jihuei (23°6.97'N 121°24.31'E), Taitung County, Taiwan, intertidal rocky habitats, coll. Li, Y.-H., 7 October 2010.

Etymology: The name is derived from the name of the nearby village, Jihuei, where the worm was collected.

Diagnosis: Platynereis with longest tentacular cirri reaching chaetiger 7. Light brown jaws, each with 5–6 lateral teeth; paragnath pattern: I = 0; II = 0; III = 3 groups of pectinate paragnaths, each group with 1 or 2 parallel transverse rows; IV = 6 parallel transverse rows and one oblique row of pectinate paragnaths (left), 7 parallel transverse rows and one oblique row of pectinate paragnaths (right); V = 0; VI = 3 parallel transverse rows of pectinate paragnaths on each side; VII –VIII = 7 groups of transverse rows, middle groups each with 3 parallel rows of pectinate paragnaths and 2 outer most groups each with 1 or 2 paragnaths. Notopodial prechaetal lobe present from about chaetiger 15 to posterior end. Neuropodial postchaetal lobe present throughout. Notochaetae with homogomph spinigers throughout, anchylosed falcigers present from chaetiger 12 to posterior end with three anchylosed falcigers on anterior chaetigers, two on mid-body chaetigers and one along posterior chaetigers. Neurochaetae with homogomph spinigers throughout; dorsal fascicle with heterogomph spinigers on chaetigers 1–4, short-bladed heterogomph falcigers with recurved tip and serrations present throughout except chaetigers 1–4; ventral fascicle with heterogomph spinigers on chaetigers 1–4 and mid-body to posterior chaetigers, short-bladed heterogomph falcigers with recurved tip and serrations present throughout except chaetigers 1–4.

Description: Holotype complete, 39.0 mm long, 79 chaetigers mm, chaetiger 10 width 1.5 mm, excluding parapodia; beige in alcohol ( Fig. 4A, B ). Prostomium as long as wide, lateral antennae as long as palps; palpophores globose, palpostyles globose, as long as wide, four pairs of tentacular cirri, longest one reaching chaetiger 7. Two pairs of eyes, in trapezoidal arrangement, subequal in size, almost fused to each other laterally; anterior eyes 1/6 as long as prostomial width. Tentacular belt about as long as chaetiger 1. Pharynx with light brown jaws, with 5–6 lateral teeth; paragnath pattern: I = 0; II = 0; III = 3 groups of pectinate paragnaths, each group with 1 or 2 parallel transverse rows ( Fig. 4C–D ); IV = 6 parallel transverse rows and one oblique row of pectinate paragnaths (left), 7 parallel transverse rows and one oblique row of pectinate paragnaths (right) ( Fig. 4C ); V = 0; VI = 3 parallel transverse rows of pectinate paragnaths on each side ( Fig. 4C, E ); VII –VIII = 7 groups of transverse rows, middle groups each with 3 parallel rows of pectinate paragnaths and 2 outer most groups each with 1 or 2 paragnaths ( Fig. 4F ). Ridge pattern of Areas VI – V – VI, υ-shaped ( Fig. 4E ).

Dorsal cirri tapered, basally attached to dorsal ligule throughout, about 1.2–1.4 times longer than dorsal ligule on anterior chaetigers, about 1.1 times longer than dorsal ligule on mid-body chaetigers, about 0.9–1.0 times as long as dorsal ligule on posterior chaetigers; dorsal cirrus lamellae present on chaetiger 17 to about chaetiger 70 ( Fig. 5A–F ). Notopodial prechaetal lobe present from about chaetiger 15 to posterior end ( Fig. 5D–F ).

Dorsal ligule conical on chaetigers 1 – 10, subconical thereafter ( Fig. 5A–F ); base of dorsal ligule slightly bulged on anterior chaetigers, elongate and broader on mid-body chaetigers, markedly elongate and broader on posterior chaetigers; small, beige glandular patches present on anterior chaetigers, glandular patches becoming light yellow, enlarged and partially or complete fused into large mass on mid-body to posterior chaetigers ( Fig. 5A–F ).

Median ligules conical on chaetigers 1–10, subconical thereafter ( Fig. 5A–F ).

Neuroacicular ligules subequal throughout. Neuropodial postchaetal lobe present throughout, about 2.0 times than neuroacicular ligules on anterior most chaetigers, about as long as, or shorter than neuroacicular ligules thereafter; neuropodial postchaetal lamellae present on chaetiger 17 to about chaetiger 65 ( Fig. 5A– F ).

Ventral ligule conical on chaetigers 1–10, subconical thereafter. Ventral cirri mid-ventrally attached to ventral edge of parapodia, about as long as ventral ligule on chaetigers 1–10, about 1.2 times longer than ventral cirri thereafter; ventral cirrus lobe present on dorsal surface of ventral cirrus from chaetiger 17 to about chaetiger 65 ( Fig. 5A–F ).

Notochaetae present from chaetiger 3 to posterior chaetigers, homogomph spinigers present throughout, anchylosed falcigers present from chaetiger 12 to posterior end with three anchylosed falcigers on anterior chaetigers, two on mid-body chaetigers and one along posterior chaetigers. Neurochaetae dorsal fascicle: homogomph spinigers present throughout, heterogomph spinigers present on chaetigers 1–4, short-bladed heterogomph falcigers with recurved tip and serrations present throughout except chaetigers 1–4. Neurochaetae ventral fascicle: heterogomph spinigers present on chaetigers 1–4 and mid-body to posterior chaetigers, short-bladed heterogomph falcigers with recurved tip and serrations present throughout except chaetigers 1–4 ( Fig. 6A–F ).

Type locality: Jihuei, Taitung City, Taiwan.

Distribution: Known only from the type locality.

Remarks: Platynereis jihueiensis sp. nov. is similar to P. bicanaliculata (Baird, 1863) and P. shihmenensis sp. nov., which have bifid tip of notopodial anchylosed falcigers ( Imajima 1972: 77–78, fig. 18i; Sun and Young 2004: 212, fig. 122H; Fig. 6B ). However, P. jihueiensis sp. nov. differs from P. bicanaliculata by having: 1) one to two parallel transverse rows of pectinate paragnaths in Area III (versus a broad oval patch); 2) six to seven parallel transverse rows and one oblique row of pectinate paragnaths in Area IV (versus a crescentic group of four or five rows); 3) seven groups of pectinate paragnaths, middle groups each with three parallel transverse rows and two outer most groups each with one or two paragnaths in Areas VII –VIII (versus seven groups, each group with two transverse rows); and 4) dorsal cirrus shorter than dorsal ligule in posterior chaetigers (versus longer than dorsal ligule) ( Imajima 1972: 77–78, fig. 18d, h; Fig. 4C, D, F ). The morphological differences between P. jihueiensis sp. nov. and P. shihmenensis sp. nov. are discussed below.

Platynereis shihmenensis sp. nov. ( Figs. 7A–C , 8A–F , 9A–F ) urn:lsid:zoobank.org:act:2DFD4A22-7215-4F0A-A01B-323223F7F76E

Material examined: Holotype: NMNS8390-4 , Shihmen (25°17.84'N 121°34.23'E), New Taipei City, Taiwan, intertidal rocky habitats, coll. P.-W. Hsueh, 2 Nov. 2003.

Etymology: The name is derived from the name of the nearby village, Shihmen, where the worm was collected.

Diagnosis: Platynereis with longest tentacular cirri reaching chaetiger 9. Light brown jaws, each with 5–6 lateral teeth; paragnath pattern: I = 0; II = 0; III = 0; IV = 4 parallel transverse rows and one oblique row of pectinate paragnaths toward jaws (left), 4 parallel transverse rows and one oblique row of pectinate paragnaths toward jaws (right); V = 0; VI = 3 non-parallel rows of pectinate paragnaths (left), 4 non-parallel transverse rows of pectinate paragnaths (right); VII –VIII = 5 groups of parallel transverse rows of pectinate paragnaths, middle groups each with 1–2 rows and 2 outer most groups each with 1 paragnath. Notopodial prechaetal lobe present throughout. Neuropodial postchaetal lobe present throughout. Notochaetae with homogomph spinigers throughout, anchylosed falciger present from chaetiger 11 to posterior end with one anchylosed falciger on each chaetiger throughout. Neurochaetae with homogomph spinigers throughout; dorsal fascicle with heterogomph spinigers on chaetigers 1–4, short-bladed heterogomph falcigers with recurved tip and serrations present throughout except chaetigers 1–4; ventral fascicle with heterogomph spinigers on chaetigers 1–4 and mid-body to posterior chaetigers, short-bladed heterogomph falcigers with recurved tip and serrations present throughout except chaetigers 1–4.

Description: Holotype complete, 37.0 mm long, 75 chaetigers, chaetiger 10 width 1.5 mm, excluding parapodia; beige in alcohol ( Fig. 7A–B ). Prostomium longer than wide, lateral antennae as long as palps; palpophores globose, palpostyles conical, four pairs of tentacular cirri, longest one reaching chaetiger 9. Two pairs of eyes, in trapezoidal arrangement, subequal in size. Tentacular belt about twice longer than chaetiger 1. Pharynx with light brown jaws, each with 5–6 teeth; paragnath pattern: I = 0; II = 0; III = 0; IV = 4 parallel transverse rows and one oblique row of pectinate paragnaths toward jaws (left), 4 parallel transverse rows and one oblique row of pectinate paragnaths toward jaws (right) ( Fig. 7C ); V = 0; VI = 3 non-parallel rows of pectinate paragnaths (left), 4 non-parallel transverse rows of pectinate paragnaths (right) ( Fig. 7D ); VII – VIII = 5 groups of parallel transverse rows of pectinate paragnaths, middle groups each with 1–2 rows and 2 outer most groups each with 1 paragnath. Ridge pattern of Areas VI – V – VI, υ-shaped ( Fig. 7D ).

Dorsal cirri tapered, basally attached to dorsal ligule throughout, about 1.0–1.1 times longer than dorsal ligule on anterior to mid-body chaetigers, about 0.9 times as long as dorsal ligule on posterior chaetigers ( Fig. 8A–F ). Small glandular patches present along the inner surface of dorsal cirri on mid-body to posterior chaetigers ( Fig. 8E ). Notopodial prechaetal lobe present throughout ( Fig. 8A–F ).

Dorsal ligule subconical on chaetigers 1–4, conical on chaetigers 5–10, triangular, blunt thereafter ( Fig. 8A– F ); base of dorsal ligule slightly elongate, broader on mid-body to posterior chaetigers; small, beige glandular patches present on anterior chaetigers, glandular patches becoming light yellow, enlarged and fused into large mass on mid-body to posterior chaetigers ( Fig. 8A–F ).

Median ligule subconical on chaetigers 1–4, conical on chaetigers 5–10, subconical with round tipped thereafter ( Fig. 8A–F ).

Neuroacicular ligules subequal in length throughout. Neuropodial postchaetal lobe present throughout, about 2.5 times longer than neuroacicular ligule on chaetigers 1–4, as long as neuroacicular ligule thereafter ( Fig. 8A–F ).

Ventral ligule subconical throughout, truncate along chaetigers 5–10. Ventral cirri mid-ventrally attached to ventral edge of parapodia, about 0.7–0.8 times as long as ventral ligule throughout ( Fig. 8A–F ).

Notochaetae present from chaetiger 3 to posterior chaetigers, homogomph spinigers present throughout, anchylosed falcigers present from chaetiger 11 to posterior end with one anchylosed falciger on each chaetiger throughout. Neurochaetae dorsal fascicle: homogomph spinigers present throughout, heterogomph spinigers present on chaetigers 1–4, short-bladed heterogomph falcigers with recurved tip and serrations present throughout except chaetigers 1–4. Neurochaetae ventral fascicle: heterogomph spinigers present on chaetigers 1–4 and mid-body to posterior chaetigers, short-bladed heterogomph falcigers with recurved tip and serrations present throughout, except chaetigers 1–4 ( Fig. 9A–F ).

Type locality: Shihmen, New Taipei City, Taiwan.

Distribution: Known only from the type locality.

Remarks: Of the nine currently known Platynereis to East Asia, P. jihueiensis sp. nov. is the only species with Area IV paragnath pattern somewhat similar to that of P. shihmenensis sp. nov., which both species have several parallel transverse rows and one oblique row of pectinate paragnaths in Area IV ( Figs. 4C , 7C ). Platynereis shihmenensis sp. nov., however, can be distinguished from P. jihueiensis sp. nov. by having: 1) no pectinate paragnaths in Area III (versus three groups of pectinate paragnaths, each group with one or two transverse rows); 2) four transverse rows of pectinate paragnaths in Area IV (versus 6–7 transverse rows); 3) three to four non-parallel transverse rows of pectinate paragnaths in Area VI (versus three parallel transverse rows); 4) five groups of transverse rows of pectinate paragnaths in Areas VII –VIII, middle groups each with 1–2 rows and two outer most groups each with one paragnath (versus seven groups of pectinate paragnaths, middle groups each with three rows and two outer most groups each with one and two paragnaths); and 5) one notopodial homogomph falciger present in each parapodium of all body regions (versus three, two and one notopodial homogomph falciger present in each parapodium of anterior, mid-body and posterior chaetigers, respectively) ( Figs. 4C–F , 7C–D ).

Figures

Fig. 1. Platynereis hemeiensis sp. nov.; holotype (NMNS 8390-1): A, anterior region, dorsal view; B, dorsal view of the pharynx; C, frontal view of the pharynx. Roman numerals indicate Area number of the pharynx. Scale bars: A = 1.0 mm; B–C = 0.5 mm.

Fig. 2. Platynereis hemeiensis sp. nov.; holotype (NMNS 8390-1): A, left parapodium, anterior view, chaetiger 4; B, left parapodium, posterior view, chaetiger 4; C, left parapodium, anterior view, chaetiger 10; D, left parapodium, anterior view, chaetiger 29; E, left parapodium, anterior view, chaetiger 50; F, left parapodium, anterior view, chaetiger 70. Abbreviations: DC, dorsal cirrus; NeAL, neuropodial acicular lobe; NePL, neuropodial postchaetal lobe; NeVL, neuropodial ventral ligule; NoDL, notopodial dorsal ligule; NoPL, notopodial prechaetal lobe; NoVL, notopodial ventral ligule; VC, ventral cirrus. Scale bars: A–F = 0.1 mm.

Fig. 3. Platynereis hemeiensis sp. nov.; A–C, E, paratype (NMNS 8390-2); D, holotype (NMNS 8390-1): A, notochaeta, homogomph spiniger, chaetiger 38; B, neurochaeta of dorsal fascicle, homogomph spiniger, chaetiger 38; C, neurochaeta of dorsal fascicle, short-bladed heterogomph falciger, chaetiger 38; D, neurochaeta of ventral fascicle, heterogomph spiniger, chaetiger 70; E, neurochaeta of ventral fascicle, short-bladed heterogomph falciger, chaetiger 38. Scale bars:A–E = 0.01 mm.

Fig. 4. Platynereis jihueiensis sp. nov.; holotype (NMNS 8390-3): A, whole animal; B, anterior body; C, paragnaths of the maxillary and oral rings; D, close-up of Area III; E, close-up of Area VI; F, close-up of Area VII/VIII. Roman numerals indicate Area of the pharynx. Scale bars: A = 2.0 mm; B = 1.0 mm; C = 0.5 mm; D = 0.1 mm; E–F = 0.2 mm.

Fig. 5. Platynereis jihueiensis sp. nov.; holotype (NMNS 8390-3): A, left parapodium, anterior view, chaetiger 3 (notopodial postchaetal lobe hindered by notopodial ventral ligule); B, left parapodium, posterior view, chaetiger 3; C, left parapodium, anterior view, chaetiger 10; D, left parapodium, anterior view, chaetiger 30; E, left parapodium, anterior view, chaetiger 50; F, left parapodium, anterior view, chaetiger 68. Abbreviations: DCLa, dorsal cirrus lamellae; NePL, neuropodial postchaetal lobe; NePLa, neuropodial postchaetal lamellae; NoPL, notopodial prechaetal lobe; VC, ventral cirrus; VCLo, ventral cirrus lobe. Scale bars: A–F = 0.1 mm.

Fig. 6. Platynereis jihueiensis sp. nov.; holotype (NMNS 8390-3): A, notochaeta, homogomph spiniger, chaetiger 50; B, notochaeta, anchylosed falciger, chaetiger 30; C, neurochaeta of dorsal fascicle, homogomph spiniger, chaetiger 50; D, neurochaeta of dorsal fascicle, short-bladed heterogomph falciger, chaetiger 50; E, neurochaeta of ventral fascicle, heterogomph spiniger, chaetiger 69; F, neurochaeta of ventral fascicle, shortbladed heterogomph falciger, chaetiger 50. Scale bars: A–F = 0.01 mm.

Fig. 7. Platynereis shihmenensis sp. nov.; holotype (NMNS 8390-4): A, whole animal; B, anterior body; C, close-up of Area IV, right side; C, closeup of Area VI. Scale bars: A = 2.0 mm; B = 1.0 mm; C–D = 0.1 mm.

Fig. 8. Platynereis shihmenensis sp. nov.; holotype (NMNS 8390-4): A, right parapodium, anterior view, chaetiger 4; B, right parapodium, posterior view, chaetiger 4; C, right parapodium, anterior view, chaetiger 8; D, right parapodium, anterior view, chaetiger 11; E, right parapodium, anterior view, chaetiger 35; F, right parapodium, anterior view, chaetiger 50. Abbreviation: NeAL, neuropodial acicular lobe; NePL, neuropodial postchaetal lobe; NoPL, notopodial prechaetal lobe. Scale bars: A–F = 0.1 mm.

Fig. 9. Platynereis shihmenensis sp. nov.; holotype (NMNS 8390-4): A, notochaeta, homogomph spiniger, chaetiger 35; B, notochaeta, anchylosed falciger, chaetiger 65; C, neurochaeta of dorsal fascicle, homogomph spiniger, chaetiger 65; D, neurochaeta of dorsal fascicle, short-bladed heterogomph falciger, chaetiger 65; E, neurochaeta of ventral fascicle, heterogomph spiniger, chaetiger 65; F, neurochaeta of ventral fascicle, shortbladed heterogomph falciger, chaetiger 65. Scale bars: A–F = 0.01 mm.