Halaelurus Gill

[[Genus Halaelurus Gill]]

The genus Halaelurus, proposed by Gill (1862) for Scyllium buergeri Müller & Henle, 1838, consists of 5 described species: H. boesemani Springer & D’Aubrey, 1972, H. buergeri Müller & Henle, 1838, H. lineatus Bass, D'Aubrey & Kistnasamy, 1975, H. natalensis (Regan, 1904) and H. quagga (Alcock, 1899) (Compagno, 1988; Compagno et al., 2005). The closely related genus Bythaelurus Compagno, 1988, previously a subgenus of Halaelurus, comprises 7 described species: B. alcocki (Garman, 1913), B. canescens (Günther, 1878), B. clevai (Séret, 1987), B. dawsoni (Springer, 1971), B. hispidus (Alcock, 1891), B. immaculatus (Chu & Meng in Chu et al., 1982) and B. lutarius (Springer & D’Aubrey, 1972). Members of the genus Bythaelurus differ from species of Halaelurus in having eyes not noticeably elevated on head vs. noticeably elevated on dorsal surface of head; gill slits not elevated above lateral head margin vs. elevated above lateral head margin; body soft with thin skin vs. body firm with thick skin; precaudal tail about 0.8-0.9 of precloacal length vs. 0.5-0.6 of precloacal length (Compagno, 1988). Representatives of the genus Bythaelurus are typically uniformly dark in coloration and have a scattered distribution in upper to lower slope regions of the Eastern Pacific and Indian Ocean, with a single species occurring in the Western Pacific. Members of the genus Halaelurus have an attractive colour pattern and occur essentially in the Indo-West Pacific, from South Africa to Japan and Australia, in insular and continental shelf regions (Compagno, 1988; Compagno et al., 2005).

Recent market surveys in eastern Indonesia produced a large collection of scyliorhinid catsharks, along with many other chondrichthyans. Included in this material were 28 individuals of a catshark that was originally identified tentatively as Halaelurus buergeri. Comparison of these Indonesian Halaelurus with material from northwestern Australia revealed two new species that differ significantly from other currently recognised members of the genus. This paper provides descriptions of these new species.