Pempheris nyctereutes Jordan & Evermann, 1903

Koeda, Keita & Bessho-Uehara, Manabu, 2024, A review of the genus Pempheris (Teleostei, Pempheridae) found in Japan and Taiwan, ZooKeys 1220, pp. 123-163 : 123-163

Pempheris nyctereutes Jordan & Evermann, 1903

Figs 7 , 8 ; Table 1 , Suppl. material 2 Standard Japanese name: Taiwan-hatampo

Pempheris nyctereutes Jordan & Evermann, 1903: 339, fig. 14 (type locality: Taipei City [Hokoto], Taiwan); Okada 1938: 179; Okada and Matsubara 1938: 179; Matsubara 1955: 590; The Marine Ecological Researching Society of Kagoshima University 1966: 19; Shen 1993: 390, unnumbered fig.; Koeda et al. 2013 a: 237; Koeda et al. 2014: 327; Tominaga 1963: 281, fig. 8; Hayashi 1984 (in part): 161; Randall and Lim 2000: 622; Hatooka 2002 (in part): 877; Hatooka and Yagishita 2013 (in part): 984; Shen and Wu 2011: 497, unnumbered fig.; Chiang et al. 2014: 183, unnumbered fig.; Koeda 2019: 927, unnumbered figs; Koeda 2020 b: 927, unnumbered figs; Koeda et al. 2022: 9.

Pempheris schwenkii (not Bleeker, 1855): Lee 1996: 97, unnumbered fig.

Diagnosis.

Counts of holotype and non-types are given in Table 1 . Dorsal-fin rays VI, 9; anal-fin rays III, 42–44; pectoral-fin rays 18–20; pored lateral-line scales 72–81 usually> 79; scale rows above lateral line 8 1 / 2–9 1 / 2; scale rows below lateral line 23–28; circumpeduncular scales 22–24; gill rakers 8 + 19–20 = 27–28; head length 30.0–30.9 %; body depth 44.6–46.9 %; eye diameter 41.0–46.4 %; upper jaw length 51.3–53.5 %; maximum 161 mm SL; snout sharp; scales weakly ctenoid, deciduous, thin, semicircular in shape, far wider than long (see Koeda et al. 2013 a: fig. 2 a); body silver to dark brown in fresh specimens; tip and anterior margin of dorsal fin zonally blackish; anal fin pale with faint black band on base; paired fins pink; posterior half of caudal fin dusky; body light brown in fixed specimen; black pigmentation on each fin usually persistent, but not in holotype; no blackish blotch on pectoral-fin base; narrow band of villiform teeth in jaws; abdomen cross-sectional outline is V-shaped.

Distribution.

Recorded only from Taiwan, Hong Kong, and Vietnam. In Taiwanese waters, this species is known from Nang-fang-ao in Yilan County, Keelung City, Aodi, Wanli, and Gongliao in New Taipei City, Tainan County, Fugang in Taitung County, Hengchung and Maobitou in Pingtung County, Lyudao, and Penghu (Fig. 8 ).

Remarks.

The taxonomic status of P. nyctereutes and P. sasakii that have similar morphology have been commonly confused. A comparison between these two species is discussed in the remarks for P. sasakii . Pempheris nyctereutes is sometimes collected by fisherman in southern Taiwan as bycatch with P. schwenkii and P. adusta , which are mainly distributed in coral-reef areas, suggesting that P. nyctereutes might be distributed in coral-reef areas. This species is also known from Ha Long Bay in Vietnam ( FRLM 49700; Koeda 2018 d) and Hong Kong ( BMNH 1939.3. 23.48). Okada (1938), Okada and Matsubara (1938), and Matsubara (1955) admitted P. nyctereutes and P. sasakii as valid species being endemic to Taiwan and Japan, respectively, and Okada (1938) gave the Japanese name “ Taiwan-hatampo ” and “ Mie-hatampo ” to them. Tominaga (1963) later proposed “ Takasago-hatampo ” for P. nyctereutes as a new Japanese name without any reasons (probably overlooking the original designation), and Koeda et al. (2022) followed that. Based on Rule 6 of the guidelines for the naming of standard Japanese names for fishes ( The Ichthyological Society of Japan 2021), “ Taiwan-hatampo ” proposed by Okada (1938) should be adopted for P. nyctereutes .

Figures

Figure 7. Fresh specimen of Pempheris nyctereutes, NMMB-P 27469, 149.4 mm SL, Penghu, Taiwan.

Figure 8. Distribution of Pempheris nyctereutes (solid triangles and solid star for holotype locality) and Pempheris sasakii (solid diamonds and open star for holotype locality) based on the collection localities of the specimens.