Author: Garman, 1913
Diagnostic Features:
Body not tadpole-shaped, moderately slender to slim and elongated, and cylindrical, tapering slightly to caudal fin; body firm and thick-skinned, with well-calcified dermal denticles; stomach not inflatable; tail moderately long, length from vent to lower caudal origin about 4/5 of snout-vent length. Head slightly depressed, narrowly rounded and not wedge-shaped in lateral view; head short, less than 1/5 of total length in adults; snout short, less than 3/4 of mouth width, thick, and slightly flattened, bluntly pointed in lateral view; snout not expanded laterally, rounded-parabolic or slightly angular in dorsoventral view, not bell-shaped; ampullal pores not greatly enlarged on snout; nostrils enlarged, but with incurrent and excurrent apertures only slightly open to exterior; anterior nasal flaps formed as enlarged, very broad, triangular lobes with angular or rounded posterior borders, without barbels, nearly meeting each other at midline of snout and extending posteriorly to overlap mouth; internarial space less than 0.5 times the nostril width; broad nasoral grooves present between excurrent openings and mouth, covered by anterior nasal flaps; eyes dorsolateral on head, narrow subocular ridges present below eyes; mouth angular or semiangular, moderately long, with lower symphysis close behind upper so that upper teeth are only slightly exposed in ventral view; labial furrows present along both upper and lower jaws, these very long and extending in front of level of upper symphysis of mouth; branchial region not greatly enlarged, distance from spiracles to fifth gill slits slightly more than half head length; gill slits lateral on head. Two dorsal fins present, about equal-sized or with the second slightly larger than the first; origin of first dorsal varying from over midbases of pelvics to about over their insertions; origin of second dorsal over the first quarter of the anal base; pectoral fins moderately large, their width slightly less to somewhat greater than mouth width; inner margins of pelvic fins not fused over claspers in adult males; claspers moderately to extremely long, fairly thick to very slender, and distally pointed or rounded, extending over half of their lengths behind the pelvic fin tips; anal fin small and not greatly elongated, smaller than pelvic and dorsal fins, its base length 0.8 to 1 times second dorsal base; origin of anal far behind pelvic bases, and insertion separated from lower caudal origin by a broad space two-thirds to about as long as the anal base; caudal fin short and broad, less than a fifth of total length in adults. No crests of denticles on the caudal margins. Supraorbital crests present on cranium. Colour light, with a varied colour pattern of dark and white spots, and dusky saddles on the sides and dorsal surface, with dark spots enlarged and partially coalescing in some species.
Remarks:
McKay (1966), described what he termed Atelomyeterus marmoratus from Western Australia, but examination of his material by the writer revealed that this record is based on two species, a hatchling A. macleayi and two specimens of a new species of Atelomycterus that differs from A. macleayi and A. marmoratus in its stouter body, different colour pattern, dorsal fin shape, smaller anal fin, and longer snout. It additionally differs from A. marmoratus in its short, stout claspers with a different arrangement of clasper glans structures. Additional specimens of this species have been collected off of northwestern Australia, and it will be described by Dr John Stevens and the writer.