Pterocerdale insolita, Hoese, Douglass F. & Motomura, Hiroyuki, 2009

Hoese, Douglass F. & Motomura, Hiroyuki, 2009, Descriptions of two new genera and species of ptereleotrine fishes from Australia and Japan (Teleostei: Gobioidei) with discussion of possible relationships, Zootaxa 2312, pp. 49-59 : 56-58

Pterocerdale insolita sp. nov.

Figures 3 and 4

Holotype: AMS I.23287–010, 43.5 mm SL female, Running Creek Mangrove, Weipa, Queensland, Australia, collected 13 October 1982, D. Hoese and D. Rennis.

Diagnosis. As for the genus.

Description. Head. Snout strongly curved in side view, broadly rounded in top view; anterior nostril at end of very short tube, immediately above upper lip, posterior nostril a larger pore just anterior to and almost touching anterodorsal margin of eye; eyes lateral on head, eye length slightly less than snout length; mouth forming an angle of 60° to longitudinal axis of body; gill opening narrow, vertical, extending ventrally from pectoral-fin base below upper margin to point just below lower pectoral base, below operculum ( Figure 4 ), broadly rounded.

Teeth. No teeth on vomer, tongue or palatine; jaw teeth conical, slightly curved; upper jaw with two rows of small, loosely attached teeth anteriorly, teeth in outer row slightly larger than those in inner row, widely spaced; lower jaw with single row of small, loosely attached teeth directed dorsally, no enlarged curved canines; along outer edge of dentary a series of blunt bony dorsoventrally flattened projections with rounded tip directed more or less horizontally (widely spaced projections appearing to be bony projections of dentary, not true teeth; probably tooth sockets), space between projections about equal to width of projections.

Scales. Nape, operculum and cheek partly scaled; nape scaled to above posterior preoperculum on midline and to above a point midway between posterior margin of eye and posterior margin of preoperculum on sides; operculum scaled on anteriorly and upper half; cheek scaled from posterior margin to below about middle of eye. Body scales cycloid, imbricate; posteriorly embedded body scales extending onto base of caudal fin, but not other fins; belly fully scaled; pectoral-fin base with embedded nonimbricate scales ventrally; prepelvic area largely covered with nonimbricate, embedded scales.

Fins. First dorsal fin low with rounded margin, membrane from dorsal spine 6 connected to body at base of second fin origin; fourth to sixth spines subequal, sixth longest (only slightly longer than other spines); no spine prolonged into a filament; when adpressed sixth spine reaches to spine of second dorsal fin. Second dorsal fin subequal in height to first dorsal fin, posterior rays not prolonged, first segmented ray unbranched, other segmented rays branched. Anal fin subequal in height to second dorsal fin, posterior rays not prolonged, all segmented rays branched. Pectoral fin with broadly rounded posterior margin, all rays branched, except uppermost and lowermost rays; pectoral fin shorter than head length, reaching only half distance to anal fin. Pelvic fins separate, with 1 spine and 4 segmented rays, first 3 rays with a single branch, fourth unbranched; tips of third and fourth rays broken off; third ray reaching only about one third of distance to anal fin. Caudal fin with rounded margin.

Head pores. Five pores along upper and rear margin of each eye, posterior nasal pore just median to posterior nostril, paired anterior interorbital pores above anterior pupil, posterior interorbital pore above a point just behind middle of eye, postorbital pore dorsoposterior to eye and infraorbital pore posterior to upper margin of pupil, behind eye; no lateral canal pores; no preopercular pores.

Head papilla. Head papillae in a transverse pattern, few papillae in each row. Papillae shown in Figure 4 .

Coloration of freshly collected holotype: Head largely dark grey, cheek light brown with 5 round spots with dark brown margins, sides of nape light brown; body largely with light brown background, paler on belly; midside with 22 short, vertical, brown bands (about one-quarter to one-third body depth at anal origin), width of bands about equal to pupil diameter; back with short vertical, brown bands above vertical brown bands; dorsal, anal, pectoral and pelvic fins translucent, without pigment; caudal fin translucent, with pale gray spots near base.

Coloration in alcohol. Similar to fresh coloration, but body more uniformly brown, with bands less prominent, but still distinct. Spotting on head and caudal fin not distinct. Fins the same brown coloration as body.

Etymology. From the Latin insolitus = strange, unusual, uncommon, all features of the new species. An adjective.

Remarks. The species was collected in a mangrove spring fed creek. The creek was in a dense stand of mangroves with the canopy covering the whole creek. When alive the fish had a very flexible body and could bend much like a blenny or Parioglossus .

Distribution. Known only from the type locality, Weipa, Queensland.

Figures

FIGURE 3. Holotype of Pterocerdale insolita, AMS I. 23287 – 010, from Weipa, Queensland, Australia.

FIGURE 4. Head of Pterocerdale insolita, showing sensory papillae on side of head; arrow indicates lower attachment of gill membrane.