Aseraggodes nigrocirratus, Randall, 2005

Randall, John E., 2005, A review of soles of the genus Aseraggodes from the South Pacific, with descriptions of seven new species and a diagnosis of Synclidopus., Memoirs of Museum Victoria 62 (2), pp. 191-212 : 205-207

Aseraggodes nigrocirratus sp nov.

Figure 12 , Tables 1–3, 9

Holotype. AMS I.26535-001, female, 79.0 mm, Australia, NSW, SE of Evans Head, off Iluka , 29°20'S, 153°29'E, 40–51 m, trawl, FRV “Kapala”, 24 May 1986.

Paratypes. AMS I.321, 89.4 mm, Australia, NSW, Sydney , Port Jackson, 33°51'S, 151°16'E , 1886; AMS I.636, mature female, 68.8 mm SL, Australia, NSW, Sydney , Port Jackson, 33°51'S, 151°16'E , J. Hunt, 1886; AMS IA.5449, 2: 55.0– 56.8 mm, NSW, Pittwater , 33°38'S, 151°18'E , dredge, M. Ward, 1932; NMV A 21382 , 61 mm, Sydney, Coogee Beach , 33°55'S, 151°15'E , R.H. Kuiter , 26 Jan 1980 ; AMS I.26535-008, 2: 65.5–82 mm, and ROM 77681 , 67 mm, same data as holotype .

Diagnosis. Dorsal rays 63–68; anal rays 47–53; most dorsal and anal rays branched; lateral-line scales 61–67, including 8–9 anterior to a vertical at upper end of gill opening; one to three pores beneath some scales on ocular side of body near base of dorsal and anal fins; vertebrae 36–38; dorsal pterygiophores anterior to fourth neural spine 8–9; body depth 2.35–2.65 in SL; head short, length 4.7–4.85 in SL; upper lip not overlapping lower lip when mouth closed; no prominent cirri on ventral edge of head; lateral line aligned with dorsal third of upper eye; eye diameter 4.6–6.25 in HL; upper eye overlapping anterior half to two-thirds of lower eye; interorbital space narrow, the vertical distance separating eyes about half eye diameter; no caudal peduncle; longest dorsal ray 1.5–1.75 in HL; caudal fin slightly pointed, its length 3.95–4.8 in SL; pelvic fins 1.8–2.0 in HL, the tip of longest ray reaching base of third anal ray; ocular side light brown with numerous small variable dark brown spots of variable size, some in form of a small cross; cirri on lengthwise membranous ridge of rays of dorsal and anal fins dark brown (appearing as small dark spots without magnification).

Description. Dorsal rays 64 (63–68); anal rays 49 (47–53); dorsal and anal rays unbranched (none double-branched), except unbranched first 9 dorsal and anal rays (first 19 dorsal and anal rays and last few rays of 43.6-mm paratype); caudal rays 18, branched, middle 16 double-branched; pelvic rays 5, branched; lateral-line scales on ocular side 65 (61–67), including 8–9 anterior to a vertical at upper end of gill openingl scales above lateral line to dorsal-fin base on ocular side about 20; scales below lateral line to anal-fin base about 24 (23–24); vertebrae 37 (two paratypes with 36, five with 37, and two with 38); erisma (counted as the first dorsal pterygiophore) about twice as thick as remaining pterygiophores, its inner two-thirds branched; only erisma before the second neural spine; space between second and third neural spines with 5 pterygiophores; space between third and fourth neural spines with 3 (2–3) pterygiophores, total 9 (8–9) dorsal pterygiophores anterior to fourth neural spine; ventroanterior margin of urohyal forming an angle of about 80° (65–80°), the corner slightly rounded.

Body depth 2.45 (2.35–2.65) in SL; body width 5.05 (5.05–5.85) in body depth; dorsal profile of head slightly more convex than ventral; HL 4.6 (4.7–4.85) in SL; snout length 2.95 (2.7–3.0) in HL; preorbital length 3.5 (3.3–3.75) in HL; eye diameter 5.85 (4.6–6.25) in HL; least vertical interorbital width 10.8 (8.9–11.1) in HL; upper eye overlapping anterior one-half to four–fifths of lower eye; upper end of gill opening on a level one-half to one eye diameter below ventral edge of lower eye; no caudal peduncle (base of lowermost caudal ray above or slightly anterior to base of last anal ray); depth of body at base of caudal fin 1.55 (1.4–1.75) in HL.

Front of upper lip not overlapping lower lip when mouth closed; maxilla extending slightly posterior to a vertical at front edge of lower eye, the upper jaw length (measured on blind side) 3.45 (3.3–3.6) in HL; blind side of upper and lower jaws with a dense band (broader posteriorly) of slender, inward-projecting, slightly curved teeth, up to about 7 rows in lower jaw and 5 or 6 in upper jaw (teeth on upper jaw beneath a thin labial fold, hence difficult to see); anterior nostril a tapering membranous tube anterior to upper edge of lower eye, just reaching fleshy base of orbit when laid back (reaching to edge of eyeball in smaller paratypes), its length in holotype about three-fourths eye diameter; posterior nostril an oblique slit in labial groove in front of base of lower eye; anterior nostril of blind side a slender membranous tube just above anterior third of upper lip; posterior nostril of blind side a short strongly tapering membranous tube dorsoposterior to anterior nostril; internarial distance on blind side about three-fourths eye diameter.

Scales ctenoid on both sides (cycloid on lateral line and partially embedded); scales of ocular side of body usually with 8–10 cteni (up to 12 in largest paratype); one to three pores beneath somc scales on ocular side of body near base of dorsal and anal fins; 3 rows of scales in interorbital space, with about another 3 rows extending onto medial and anterior part of each eye; scales on ocular side of head progressively smaller anteriorly and ventrally, the most anterior at front of snout very small and without cteni; fleshy front of snout with small short cirri on edge; scales on blind side of head gradually replaced anteriorly by papillae, ending with small slender papillae on edge of snout; broad zone of small fleshy papillae on blind side dorsal to upper jaw; ventral edge of head with cirri as long as half eye diameter; no cirri along edge of operculum at gill opening on either side. Lateral line straight midlaterally on both sides of body, directed on ocular side toward dorsal third of upper eye; supratemporal branch of lateral line on blind side of head faintly visible, continuing dorsally 2 to 3 scale rows below dorsal fin, persisting to about middle of body.

Dorsal and anal fins with a basal sheath of 2 to 3 rows of scales; lengthwise thin membranous ridge basally on dorsal and anal rays with well-spaced dark brown cirri on free edges except posterior rays; small scales basally on membranous ridges of anterior dorsal rays on both sides (first 19 rays of holotype), the height of the scale bands progressively shorter posteriorly; about basal third of caudal fin with scales on both sides, with small, well-spaced, isolated scales, with a few prominent cteni on each side of rays to within outer third of fin.

Origin of dorsal fin anterior to lower fourth of upper eye, the predorsal length 3.8 (3.25–3.8) in HL; first dorsal ray 2.8 (2.6–2.95) in HL; longest dorsal ray 1.7 (1.5–1.75) in HL; origin of anal fin below base of fifteenth or sixteenth dorsal ray and about one-half eye diameter behind posterior end of operculum, the preanal length 3.8 (3.75–4.15) in SL; length of first anal ray 2.8 (2.5–2.9) in HL; longest anal ray 1.7 (1.5–1.75) in HL; caudal fin slightly pointed, relatively shorter with growth, 4.7 (3.95–4.8) in SL; ocular-side pelvic fin on ventral edge of body; base of blind-side fin adjacent anteriorly, its origin slightly posterior to ocular-side fin; third pelvic ray of each fin longest, reaching to base of third anal ray, 2.0 (1.8–2.0) in HL; anus directly before base of first anal ray at end of short semicircular column of ridged fleshy tissue, an upper anterior triangular part covering opening; genital papilla on ocular side of base of first anal ray, very large, its length equal to orbit diameter; membrane from near base of last pelvic ray of ocular side joined to extreme base of genital papilla.

Colour of holotype in alcohol: ocular side light grey-brown with numerous small dark brown spots on head, body, and basal scaly part of caudal fin, some as small dark crosses from dark edges of adjacent scales; dorsal and anal fins with translucent membranes, the rays light yellowish brown, most with 1–3 small dark brown spots associated with a fleshy cirrus; naked part of caudal fin like dorsal and anal fins, but small dark spots on the rays without a cirrus; blind side of body pale yellowish, slightly dusky in a broad peripheral zone. Figure 12 taken of a fresh specimen, very similar to colour in preservative; pale spots on figure from missing scales.

Etymology. Named nigrocirratus from the Latin, in reference to the black cirri on the dorsal and anal rays of the ocular side of this species.

Remarks. Aseraggodes nigrocirratus is presently known only from NSW from latitudes 29°20'S to 33°55'S, from inshore to about 50 m.

Randall and Meléndez (1987) mentioned this species in their description of Aseraggodes bahamondei as probably undescribed, noting that it also has pores under some scales of the ocular side near the base of the dorsal and anal fins. They attributed the presence of these pores in bahamondei to the production of a strong skin toxin, probably comparable to that of the species of Pardachirus ( Clark and George, 1979) .

Although Aseraggodes bahamondei is similar in its colouration, general morphology, and the low number of dorsal pterygiophores anterior to the fourth neural spine to A. nigrocirratus , it is readily distinguished by having a caudal peduncle (though this difference is actually very slight), 39 to 40 vertebrae, 75–86 lateral-line scales, and by attaining a significantly larger maximum size of at least 156 mm SL.

Of the known species of the genus, A. nigrocirratus is most similar to A. lenisquamis , described above. The two have the same vertebral count (36–38), the same number of dorsal pterygiophores anterior to the fourth neural spine (8–9), and nearly the same number of dorsal and anal rays and lateral-line scales (see Tables 1–3). They differ mainly in the structure of the scales. Those of nigrocirratus are typical of most species of the genus, with prominent cteni that project well beyond the posterior margin of the scales, and the exposed surface of the scales with a pattern like miniature scales. The scales of lenisquamis are generally more pointed posteriorly and are covered with soft cutaneous tissue, such that only the tips of the cteni project beyond the scale margins (each capped with soft tissue). Also the lateral-line scales and scattered other scales of lenisquamis have small fleshy cirri. Three different proportional measurements of the two species are evident in Tables 7 and 9. A . lenisquamis has a longer snout, broader caudal-fin base, and is broader, and shorter caudal fin.

Six specimens of AMS I.24035-003, 42.0– 52.3 mm SL, collected in 1 m at Wagstaff Point, Brisbane Waters, NSW, 33°28'S, 151°21'W, in 1982 include four provisionally identified as A. nigrocirratus and two of about 45 mm SL that appear to be hybrids of A. lenisquamis and A. nigrocirratu s. The latter two specimens have scales of both types, though mainly those typical of A. lenisquamis , and only a few short cirri on lateral-line scales near the middle of the body. Both specimens are misshapen and difficult to measure. The four specimens identified as A. nigrocirratus are excluded from the type series.

Similarly, the two specimens of AMS I.38279-001, 79.4–83.0 mm, collected by trawl in 48 m off the Clarence River, NSW at 29°19.5'S, 153°24'E, include one of A. lenisquamis (the larger) and one that is regarded as a hybrid of A. nigrocirratus and A. lenisquamis . This lot is also undivided, and the specimen of lenisquamis is not designated as a paratype. The presumed hybrid has scales characteristic of each of the species, and it is intermediate in the three proportional measurements that are diagnostic.

Figures

Figure 12. Holotype of Aseraggodes nigrocirratus, AMS I.26535–001, 79.0 mm SL, off Iluka, NSW (K.J. Graham).