Selenanthias barroi (Fourmanoir)

Gill, Anthony C., Pogonoski, John J., Moore, Glenn I. & Johnson, Jeffrey W., 2021, Review of Australian species of Plectranthias Bleeker and Selenanthias Tanaka (Teleostei: Serranidae: Anthiadinae), with descriptions of four new species, Zootaxa 4918 (1), pp. 1-116 : 107-110

Selenanthias barroi (Fourmanoir)

Figures 45–46 ; Tables 1–16, 30

Common name: Barro’s Fairy Basslet

Plectranthias barroi Fourmanoir 1982: 60 , fig. 2 (type locality: Chesterfield Islands , Coral Sea).

? Selenanthias sp.— Sih et al. 2017: table 1 (central Great Barrier Reef).

Diagnosis. The following characters distinguish S. barroi from congeners: dorsal fin with 15–16 segmented dorsalrays; lower gill rakers 22–25; males without large black blotch on soft part of anal fin.

Description of Australian specimens. Dorsal rays X,16, all segmented rays branched; anal rays III,7, all segmented rays branched; pectoral rays 15, upper 1 and lower 0–1 rays unbranched; pelvic fin I, 5, all segmented rays branched; upper procurrent caudal-fin rays 7; lower procurrent caudal-fin rays 7; principal caudal-fin rays 9+8; branched caudal fin rays 8+7; total caudal-fin rays 31; lateral line complete with 35–39 tubed scales; scales above lateral line to origin of dorsal fin 4–5; scales above lateral line to base of fifth dorsal spine 4–5; scales below lateral line to origin of anal fin 13–14; diagonal rows of scales on cheek 8–10, including a row over preopercular canal; predorsal scales 38–44, extending almost to upper lip; circumpeduncular scales 18; gill rakers 8–11+24–25 = 33–35, all well-developed; pseudobranchial filaments 20–22; branchiostegal rays 7.

Vertebrae 10+16; supraneurals 3; predorsal formula 0/0+0/2/1+1; dorsal pterygiophores in interneural spaces 9–13 1/1/1/1+1/1 or 1/1/1/1+1/1+1; terminal dorsal pterygiophore in interneural space 19; 1–2 trisegmental pterygiophores associated with dorsal fin; 3–4 trisegmental pterygiophores associated with anal fin; terminal anal pterygiophore in interhaemal space 5; ribs present on vertebrae 3 through 10; epineurals present on vertebrae 1 through 11–12; parhypural and hypurals autogenous; well-developed hypurapophysis on parhypural; epurals 3; single uroneural (posterior uroneural absent); ventral tip of cleithrum with well-developed posteroventral process; proximal tip of first anal-fin pterygiophore near distal tips of parapophyses on vertebra 10.

Dorsal-fin spines with fleshy tabs on their distal tips; fourth dorsal spine longest; dorsal fin not incised before first segmented-fin ray (tenth spine 75.2–83.5 % length of first segmented ray); second anal-fin spine longest and stoutest; anal fin pointed with second segmented ray elongate; caudal fin emarginate, second to uppermost branched ray elongate; lower 9 pectoral fin rays somewhat thickened, with membranes between thickened rays incised; eighth to tenth (counting from dorsal-most) pectoral ray longest, reaching just part vertical through anal origin; pelvic moderate to long, reaching point ranging from anal-fin origin to anterior third of anal fin, second segmented ray longest.

Morphometric data are summarised in Table 30.

Mouth large, slightly oblique, posterior margin of maxilla reaching vertical through posterior margin of pupil; maxilla expanded posteriorly, with long, low, lateral ridge running parallel to dorsal margin; splint-like supramaxilla present; mouth terminal; upper jaw with 1–2 anteriorly projecting, short stout outer canines on either side of symphysis, flanked internally by villiform band with about 6–7 rows of depressible, smaller, sharp-tipped teeth, with inner rows becoming progressively longer and caniniform near symphysis; band reducing to 1–2 rows posteriorlyly; front of lower jaw with 1–2 pairs of anteriorly projecting stout, fixed enlarged teeth laterally; behind these, villiform band of about 5–6 rows of small depressible teeth at symphysis, teeth becoming progressively longer and caniniform on inner rows towards symphysis, reducing to 1–2 rows posteriorly; 2–3 pairs of enlarged, curved canine on middle of jaw; vomer with 3–5 rows of conical teeth arranged in chevron (small specimens) to triangular patch (largest specimen) patch, the posterior teeth enlarged; palatine with band of 3–4 rows of conical teeth; ectopterygoid and mesopterygoid edentate; tongue narrow, pointed and edentate.

Opercle with 3 flat spines, middle spine longest, upper spine concealed by scales; posterior and ventral margin of preopercle with continuous series of 40–68 distinct serrations, these largest near angle of preopercle; interopercle with 7–13 strong serrations; subopercle with 4–9 strong serrations; posttemporal with 5–8 strong serrations; largest specimen with about 6–7 fine serrations on IO1, none apparent on smaller specimens. Anterior nostril positioned at middle of snout, tubular with small flap on posterior rim; posterior nostril at anterior border of orbit, with raised rim but no flap.

Scales ctenoid with basal cteni; lateral line broadly arched over pectoral fin following body contour to caudalfin base; scales on maxilla, mandibles, chin, anterior part of branchiostegals, snout above nostrils and infraorbitals (including ventral tip of IO1); no auxiliary scales on head or body; spinous dorsal fin with intermittent row of scales along base of fin; soft dorsal and anal fin with low scaly sheath basally, with some small scales extending on to fin membranes; caudal fin with scaly basal sheath, with small scales extending on to basal third to half of fin membranes; pectoral fins with basal sheath and small scales extending on to fin membranes.

Colour in life: Not recorded for the Australian specimens. Fourmanoir (1982) provided the following fresh colour description of the type specimens (our translation from the French): “Pale pink color, almost white fins. The head is orange, a pink line follows the upper edge of the maxilla and passes through the preoperculum. The most prominent spot, dark orange, is at the base of the dorsal, between the spines VII and X; there are also two small dark orange spots under spines IV and V, a spot in the middle from the base of the soft dorsal, finally a less distinct spot at the origin of the caudal peduncle. From the angle of the operculum five to six rows of lateral and ventral longitudinal scales have a white mother-of-pearl colour.”

Colour in preservative: Smaller specimens ( Figure 46A ): head, body and fins tan, except for indistinct dusky pupil-sized blotch over lower part of dorsal fin between spines 9 and 10, extending on to upper body. Largest specimen ( Figure 46B ): Head and body tan, with wedge-shaped silvery white mark extending from behind eye to middle of subopercle; narrow silvery white stripe from behind posterodorsal part of maxilla to junction between interopercle and subopercle; upper part of head with two indistinct narrow oblique stripes, one from upper part of preopercle to just above middle of eye, the other from upper edge of opercle to midline above vertical through posterior edge of pupil, converging with corresponding line from other side; sides of body with silvery white spots covering scales, these scattered on upper part of body, but more regularly distributed on sides behind pectoral fin, forming about four or five broken lines, which mostly extend to above anal origin; fins mostly tan except spine and leading edge of pelvic fin abruptly white.

Habitat and distribution. See Remarks

Comparisons. See above key.

Remarks. Fourmanoir (1982) described Plectranthias barroi from the holotype and four paratypes collected in 300 m in the Chesterfield Islands, New Caledonia. The species was tentatively transferred to the genus Selenanthias by Randall (1996), a move that was later followed by Heemstra & Randall (1999) and Anderson (2018). We herein newly record it from Australia on the basis of three specimens trawled in 306 m west of the Lihou Reefs, Coral Sea in 1988. The specimens agree well with Fourmanoir’s description and figure. As noted above, it is likely that Sih et al. ’s (2017) record of S. sp. from the central Great Barrier Reef off Townsville (ca 18°S to 19°S in 143–179 m) is also referable to this species.

Material examined. Queensland, Australia. QM I. 25564, 122.5 mm SL , QM I.25573, 2: 71.7–79.4 mm SL, Coral Sea , west of Lihou Reefs, 17°41′S, 150°06′E, 306 m, trawl, Raptis Seafoods, Apr 1988 .

Figures

FIGURE 45. Distribution records for Selenanthias barroi (closed circles; eastern-most record is type locality) and Australian S. analis (open circles).

FIGURE 46. Selenanthias barroi, preserved specimens, west of Lihou Reefs, Coral Sea, Australia: A) QM I.25573, 71.7 mm SL; B) QM I.25564, 122.5 mm SL. Photos by A.C. Gill.