Perinereis aibuhitensis ( Grube, 1878 )

Hsueh, Pan-Wen, 2024, Positive association between PTN polymorphisms and schizophrenia in Northeast Chinese Han population., Zoological Studies 63 (39), pp. 141-149 : 4-5

Perinereis aibuhitensis ( Grube, 1878) ( Fig. 2 )

Nereis (Perinereis) aibuhitensis Grube 1878: 89–90, p1 . 5, fig. 3; Horst 1924: 168–169, p1. 33, figs. 4–6.

Nereis aibuhitensis Monro 1934: 361–362 .

Neanthes linea Treadwell 1936: 268–270 , fig. 19a–e.

Neanthes orientalis Treadwell 1936: 270–272 , fig. 19f–i.

Perinereis aibuhitensis Fauvel 1932: 106 , 1953: 209–210, fig. 107a; Russell 1962: 6–7; Wu 1967: 70; Wu et al. 1981: 171–172, figs. 107A–J, 108A–H, 109A–F; Wu et al. 1985: 189–193; Hylleberg et al. 1986: 3–5, fig. 2A–Q; Hutchings et al. 1991: 245–246, fig. 2a–e.

Material examined: Changhua County: 1 specimen, NMNS 8748-1, Xigung (23°52.29'N, 120°17.60'E), habitat type: ISSB, 17 March 2007; 1 specimen, NMNS 8748-2, Fubao (24°02.83'N, 120°22.75'E), habitat type: ISSB, 18 March 2007; 1 specimen, NMNS 8748-3, Fubao Bridge (24°02.68'N, 120°22.91'E), habitat type: ISSB, 18 March 2007; 3 specimens, NMNS 8748 -4 – 6, Fubao Bridge (24°02.69'N, 120°22.90'E), habitat type: ISSB, 1 May 2007; 1 specimen, NMNS 8748-7, Zhuoshui (23°51.50'N, 120°22.75'E), habitat type: ISSB, 20 March 2009; 1 specimen, NMNS 8748-8, Zhuoshui (23°51.50'N, 120°22.75'E), habitat type: ISSB, 7 June 2010; 1 specimen, NMNS 8748-9, Xianxi (24°05.17'N, 120°25.13'E), habitat type: ISSB, 22 April 2017. Chiayi County: 1 specimen, NMNS 8748-10, Bazang (23°19.51'N, 120°07.78'E), habitat type: ISSB, 7 January 2007.

Description: Based on five complete specimens ( NMNS 8748-1, 4, 6, 8,10; all atoke) and five incomplete specimens ( NMNS 8748-2–3, 5, 7, 9; all atoke); complete specimens for general body morphology, incomplete specimens for anterior body morphology and paragnath pattern only: Body length 75.0–179.0 (n = 5) mm with 152–202 (n = 5) chaetigers, chaetiger 10 width 1.0–5.0 (n = 10) mm, excluding parapodia; beige in alcohol ( Fig. 2A, B ). Prostomium wider than long, lateral antennae antero-lateral, shorter than palps, palpophores globose, palpostyles spheroid. Four pairs of tentacular cirri, longest one reaching chaetiger 2–6 (n = 10). Two pairs of eyes, in trapezoidal arrangement. Tentacular belt about 1.1–1.4x (n = 10) longer than chaetiger 1. Pharynx with dark brown jaws, each with 5–7 (n = 10) teeth; paragnath pattern: I = 3–6 (mostly 4 or 5, one case of 3 and 6; n = 10, same sample size on following areas), in triangle or cluster; II = 12–23 (left), 11–26 ones (right), in 2–3 oblique rows; III = 40–57 (center region with 27–56 cones, in 3–4 transverse rows; mostly 2 lateral regions, each with 0–3 or 0–4 cones; one case of 4 lateral regions, outer lateral regions with 2 cones, inner lateral regions with 6 or 8 cones, in longitudinal lines); IV = 14–25 (left), 15–23 (right), in 2–3 oblique rows; V = 3, in triangle; VI = mostly 2 short bars, one case of 1 additional cone (left), mostly 2 short bars, one case of 3 short bars (right), in transverse row; VII –VIII = 39–58, in 3–4 rows. Ridge pattern of areas VI – V – VI, u-shaped ( Fig. 2A, B ).

Dorsal cirri digitiform, medially attached to dorsal ligule on anterior to mid-body chaetigers, about 0.4–0.5x as long as dorsal ligule, attached 1/3 to base of dorsal ligule on posterior chaetigers, about 0.2x as long as dorsal ligule ( Fig. 2C–E ).

Dorsal ligule subconical throughout, about 1.8x longer than median ligule on anterior chaetigers, about 2.0–2.2x longer than median ligule on mid-body to posterior chaetigers; center lobe of dorsal ligule with one irregular-shaped glandular mass on posterior chaetigers ( Fig. 2E ). Notopodial prechaetal lobe absent.

Median ligule subconical throughout, as long as neuroacicular ligule on anterior and posterior chaetigers, greatly longer than neuroacicular ligule on mid-body chaetigers ( Fig. 2C–E ).

Neuroacicular ligule with predominant inferior lobe on anterior chaetigers, about 0.4–0.5x as long as ventral ligule, inferior and superior lobes subequal in length on mid-body to posterior chaetigers, about 0.5x as long as ventral ligule on mid-body chaetigers, about 1.5x longer than ventral ligule on posterior chaetigers. Neuropodial postchaetal lobe absent. Ventral ligule subconical throughout. Ventral cirri digitiform, mid-ventrally attached to ventral edge of parapodia, as long as ventral ligule throughout ( Fig. 2C–E ).

Notochaetae present from chaetiger 3 to posterior chaetigers, homogomph spinigers present throughout. Supra-acicular fascicle of neuropodia: homogomph spinigers and long-bladed heterogomph falcigers with serrations present throughout. Subacicular fascicle of neuropodia: long-bladed heterogomph falcigers with serrations and heterogomph spinigers present throughout ( Fig. 2F ).

Pygidium with anus crenulated; anal cirri cirriform, as long as last 3–8 (n = 5) chaetigers.

Distribution: Australia, China, India, Andaman Islands, Indonesia (Sulawesi, Sumatra, Java), Philippines ( Hutchings et al. 1991), Taiwan ( Wu 1967).

Remarks: Morphology of examined specimens in the present study largely agrees with redescription of P. aibuhitensis ( Grube, 1878) in Hutchings et al. (1991: 245, fig. 2a–c) ( Fig. 2A–F ). However, some morphological discrepancies can be noted between present specimens and redescription: 1) several present specimens have greater number of paragnaths on areas I (up to 6 versus 4), II (mostly with 16–23 versus 6–14), III (40–57 versus 8–23); and 2) one present specimen has two short bars and one cone on left side of area VI and three short bars on left side of area VI (versus always 2 short bars on each side of area VI) ( Hutchings et al. 1991: 245, fig. 2a–c). These discrepancies might be due to the size-related variations. Moreover, present specimens have one glandular mass on center lobe of dorsal ligule on posterior chaetigers ( Fig. 2E ), which is not mentioned by neither Wu (1967), nor Hutchings et al. (1991: 245); however, this feature had been illustrated in Hylleberg et al. (1986: 4, fig. 2E, J). This species is commonly found in soft bottom habitats of river mouths and coastal flats of western Taiwan.

Figures

Fig. 2. Perinereis aibuhitensis (Grube, 1878); A, B (NMNS 8748-9), C–F (NMNS 8748-6): A, anterior body region, dorsal view; B, anterior body region, ventral view; C, right parapodium, anterior view, chaetiger 10; D, right parapodium, anterior view, chaetiger 51; E, right parapodium, anterior view, chaetiger 101; F, neuropodial subacicular fascicle chaetae. Abbreviations: HeF = heterogomph falciger; HeS = heterogomph spiniger. Scale bars:A, B = 0.5 mm; C–E = 0.2 mm; F = 0.02 mm.