Stolephorus continentalis, a new anchovy from the northwestern South China Sea, and redescription of Stolephorus chinensis (Günther 1880) (Clupeiformes: Engraulidae)

Abstract

Stolephorus continentalis sp. nov. is described from 36 specimens from Hong Kong and northern Vietnam. The new species is closely related to the endemic Chinese anchovy S. chinensis (Gunther 1880), which is redescribed with a lectotype designated, with both species having a long upper jaw with the posterior tip just reaching to the posterior border of the preopercle; no predorsal scute; the posterior preopercular border rounded, convex; the posterior tip of the depressed pelvic fin not reaching to vertical through dorsal-fin origin; a pair of dark patches behind the occiput without a following pair of dark lines; and no black spots below the eye and lower-jaw tip. However, the new species is distinguished from S. chinensis in having higher total gill-raker counts on the first, second, third, and fourth gill arches (43–48, 33–40, 23–26, and 18–21, respectively vs. 35–41, 29–34, 19–24, and 16–19), and longer pectoral (16.5–19.2 % SL vs. 15.8–16.4 %) and pelvic fins (9.1–11.6 % SL vs. 8.2–8.3 %). Examination of the specimens previously considered as S. chinensis from Southeast Asia revealed that they differed from true S. chinensis and S. continentalis in having eight transverse scales (vs. 10 in the latter two species). The applicable scientific name for the Southeast Asian species is suggested here as Stolephorus oceanicus Hardenberg 1933.