Notes on the biology of a Red Sea goby, Silhouettea aegyptia (Chabanaud, 1933) (Teleostei, Gobiidae)

Miller P.J., Fouda M.M.

Published date: December 1986
Volume: 10
Number: 4
Pagination: 395-409
Publisher: Société Française d'Ichtyologie
doi: https://doi.org/10.26028/cybium/1986-104-008
Abstract

Silhouettea aegyptia (Chabanaud, 1933) (= Minictenogobiops sinaii Goren, 1978) is a small, littoral gobiid fish occurring in the northern Red Sea, Suez Canal, and Bardawil Lagoon, Sinai. The species has been collected by the authors at Al-Ghardaqa and Ras Gemsa (Red Sea), and Lake Timsah (Suez Canal); it was present at Kabret, on the Bitter Lakes, by 1924. Living on sand, S. aegyptia has cryptic coloration and behaviour. Diet is chiefly harpacticoid copepods and nematodes. Maximum size (Lake Timsah) is about 5 cm, and longevity under two years. The species is gonochoristic, male genitalia showing typical gobiid sperm-duct glands but not an interstitial cell mass. External sexual dimorphism involves first dorsal fin-rays. Gonadosomatic index in females may reach at least 10% with ripe oocyte diameter at least 0.64 mm and fecundity recorded at 305-405. Maturity is reached at less than one year old, at over 20-21 mm standard length. Breeding probably commences in May at Al-Ghardaqa, with repeat-spawning indicated by oocyte size-frequency distribution. Life-history pattern seems to relate to an epibenthic ecotope and should promote success as a Lessepsian migrant.

Keywords: cryptic behaviour - cryptic coloration - Fecundity - Gobiidae - Red Sea - Reproduction - Sexual dimorphism - Silhouette aegyptia - Suez Canal
PDF available for everyone

Supplementary files

AttachmentSize
PDF icon 13-Miller[104]395-409.pdf3.25 MB