Author: Garman, 1906
Field Marks:
Flabby, soft-bodied catsharks with crests of saw-like denticles on dorsal (and sometimes ventral) caudal margin, rather small pectoral fins with width less than mouth width, usually short, rounded snouts less than mouth length, and subocular ridges well developed under eyes.
Diagnostic Features:
Body not tadpole-shaped, slender and cylindrical, tapering slightly to caudal fin; body soft and flabby, with weakly 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 pointedrounded in lateral view and not wedge-shaped; head short to moderately long, between 1/4 and 1/5 to less than 1/5 of total length in adults; snout short to moderately long, less than 4/5 of mouth width, thick, and slightly flattened, bluntly pointed in lateral view; snout not expanded laterally, rounded-parabolic and slightly bell-shaped in dorsoventral view; ampullal pores not greatly enlarged on snout; nostrils of moderate size, with incurrent and excurrent apertures only partly open to exterior; anterior nasal flaps broadly triangular, elongated and lobate, or reduced and pointed, without barbels, well separate from each other and falling somewhat anterior to mouth; internarial space about 0.8 to 1.1 times in nostril width; no nasoral grooves; eyes dorsolateral on head, narrow subocular ridges present below eyes; mouth angular or semiangular, moderately long with lower symphysis well behind upper so that upper teeth are exposed in ventral view; labial furrows present along both upper and lower jaws, these short and ending well behind level of upper symphysis of mouth; branchial region not greatly enlarged or slightly enlarged (P. xaniurus), distance from spiracles to fifth gill slit 2/5 to 3/5 of head length; gill slits lateral on head. Two dorsal fins present, about equal-sized or with second definitely larger than first; origin of first dorsal varying from slightly in front of the pelvic origins to about over their insertions; origin of second dorsal varies from about over the anal origin to slightly behind the anal midbase; pectoral fins moderately large, their width subequal or somewhat less than mouth width; inner margins of pelvic fins not fused over claspers in adult males; claspers moderately long, fairly thick, and distally pointed, extending about half of their lengths behind the pelvic fin tips; anal fin moderately large but not greatly elongated, about as large as pelvic fins or larger, subequal to larger than the second dorsal and larger than the first dorsal, its base length subequal to about 1.7 times second dorsal base; origin of anal close behind to far behind pelvic bases, and insertion separated from lower caudal origin by a narrow notch to a broad space over half the anal base; caudal fin moderately elongated, over or less than a fourth of total length in adults. A well-developed crest of denticles on the dorsql caudal margin, and sometimes on the preventral margin, dorsal crest rounded on its upper surface and somewhat asymmetrical in adults; small median denticles between upper crest denticles usually in more than five rows; supraorbital crests absent from cranium. Colour light grey or brown to dark grey or blackish-grey, without a conspicuous colour pattern.
Remarks:
The genus Dichththys was proposed by Chan (1966) for D. melanobranchius. Springer (1979) reduced Dichichthys to a subgenus of Parmaturus, with P. melanobranchius and his new species P. campechiensis, while including P. pilosus and P. xaniurus in the nominate subgenus Parmaturus. Springer also proposed a new subgenus, Compagnoia, for P. manis and P. stenseni, which are Apristurus-like species more properly placed in that genus.
Recently Chu et al. (1983) placed P. melanbranchius and Galeus boardmani in the genus Figaro, along with their new species F. piceus. However, as a tentative measure I retain Springer's (1979) arrangement, however unsatisfactory, and retain melanobranchius in Parmaturus; Figaro piceus is considered a possible synonym based on the adult of P. melanobranchius. See the remarks under the genus Galeus for further comments on the genus Figaro, which, if constituted as Chu et aL (1983) suggest to include all the Parmaturus-Galeus-like species with subcaudal crests of denticles, would have to include Parmaturus pilosus, the type species of Parmaturus. This would make Figaro a junior synonym of Parmaturus, and would orphan P. xaniurus and P. campechensis, species without subeaudal crests that are respectively close to P. pilosus and P. melanobranchius. There may be a new species of Parmaturus off New Zealand, but this is uncertain at present.