Jaydia novaeguineae Valenciennes 1832
Creators: name: Bogorodsky, Sergey V.
name: Alpermann, Tilman J.
name: Mal, Ahmad O.
name: Gabr, Mohamed H.
Publisher: name: Zenodo
Year: 2014
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Actinopterygii
Perciformes
Apogonidae
Jaydia
Jaydia novaeguineae

description: Jaydia novaeguineae (Valenciennes, 1832)
(Fig. 7)
Material examined. SMF 35007 (1: 5.6 cm); SMF 35008 (2: 8.1–8.9 cm); KAUMM 58 (2: 7.2–8.0 cm); KAUMM 60 (1: 7.0 cm).
Description. Dorsal-fin rays VII + I,9; anal-fin rays II,8; pectoral-fin rays 15 or 16 (3: 15, 1: 15/16, 2: 16); lateral-line scales 26 or 27 (1: 26, 5: 27); median predorsal scales 4; gill rakers 3 or 4 + 10–12; developed gill rakers 2 + 9 or 10 (3: 2 + 9, 3: 2 + 10); gill rakers on first ceratobranchial 8; body depth 2.7–3.1 in SL; head length 2.4–2.6 in SL; snout length 4.3–4.6 in head length; eye diameter 3.7–4.0 in head length; interorbital width 5.1–5.6 in head length; upper jaw extending to middle of orbit or slightly beyond; preopercular ridge smooth, weakly crenulate at angle; edge of preopercle smooth at angle and ventrally, the posterior margin weakly serrate; fourth dorsal spine longest, the length 2.2–2.5 in head length; pectoral-fin length 4.2–4.5 in SL; tips of pelvic fins not reach anus; caudal peduncle longer than its depth, the depth 1.1–1.4 in its length; caudal fin truncate, shorter than head, the length 4.0– 4.8 in SL.
Color (when fresh): light grey dorsally, the edges of scales dusky, shading to silvery on side and ventrally, with up to eight narrow, indistinct, dusky bars in some specimens; head except opercle covered with minute black dots; edge of the gill opening outlined with black in some specimens; top of snout with diffuse black blotch; upper half of iris black; outer half of first dorsal fin black; second dorsal and caudal fins dusky; pelvic-fin spine, anterior part of anal fin, and lower rays of caudal fin white (Fig. 7 A); peritoneum pale (Fig. 7 B).
Distribution. Known from Philippines and Papua New Guinea, west to Madagascar (Gon 1997), also reported from Kenya (O. Gon, pers. comm.) and the southern Red Sea (this study).
Remarks. Typically lives on sand bottom in shallow waters from depths of 22–62 m, trawled specimens were collected from 40–55 m on an open sandy area. Gon (1997) reported maximum size 8.0 cm SL, one of two specimens of lot SMF 35008 is 8.8 cm SL, the largest specimen known for the species. The genus Jaydia was revised, as a subgenus of Apogon, by Gon (1997) who recognized 10 species. Recently Allen & Erdmann (2012) added three other species to the genus (J. argyrogaster (Weber, 1909), J. melanopus (Weber, 1911), and J. photogaster (Gon & Allen, 1998)), and later, Mabuchi et al. (2014) listed 16 species in the genus. The genus is characterized by a combination of the following characters: smooth or weakly serrated preopercular edge, fourth dorsal-fin spine longest, and the presence of light organs. Members of the genus are typically associated with soft substrata, often on open sandy areas. Gon (1997) divided the genus into three groups, each differs by color pattern and the type of serration of the preopercle. Only two other species of the genus are reported from the Red Sea, J. queketti (Gilchrist, 1903) and J. smithi Kotthaus, 1970, and each belong to a different group. Jaydia queketti can be distinguished by its color pattern consisting of dark brown spots on scales forming longitudinal rows, and by a smooth preopercular ridge and edge. Jaydia smithi may be confused with J. novaeguineae because of its similar overall appearance, but the former has a serrate preopercular ridge (at least ventrally), preopercular edge weakly serrate, a curved black stripe in the middle of the second dorsal fin, and a narrow black edge of the preopercle. The black edge of the gill membrane that was well-visible in some specimens possibly represents a sexual dimorphism, but more material is needed to solve this question.
description: Published as part of Bogorodsky, Sergey V., Alpermann, Tilman J., Mal, Ahmad O. & Gabr, Mohamed H., 2014, Survey of demersal fishes from southern Saudi Arabia, with five new records for the Red Sea, pp. 401-437 in Zootaxa 3852 (4) on pages 418-420, DOI: 10.11646/zootaxa.3852.4.1, http://zenodo.org/record/225360