Pezichthys amplispinus, Last & Gledhill Csiro, 2009

Last, Peter R. & Gledhill Csiro, Daniel C., 2009, A revision of the Australian handfishes (Lophiiformes: Brachionichthyidae), with descriptions of three new genera and nine new species 2252, Zootaxa 2252 (1), pp. 1-77 : 34-38

Pezichthys amplispinus sp. nov.

Figs 2 , 3 , 14, 15; Tables 3, 7–10

Holotype. CSIRO H 4448–01 , 43.8 mm SL, east of Bermagui , New South Wales, 36° 29'S, 150° 12'E, 118– 121 m, 1 Dec. 1996.

Paratypes. 6 specimens (30–46 mm SL): CSIRO H 4448–02 , 30.1 mm SL, same data as holotype ; CSIRO H 4449–01 , 45.2 mm SL, east of Bermagui , New South Wales, 36° 22'S, 150° 12'E, 78–84 m, 30 Nov. 1996 ; CSIRO H 4450–01 , 40.5 mm SL, east of Disaster Bay , New South Wales, 37° 19'S, 150° 12'E, 112 m, 2 Dec. 1996 ; CSIRO H 4459–01 , 45.7 mm SL, north-east of Eden , New South Wales, 36° 56'S, 150° 03'E, 74 m, 3 Dec. 1996 ; CSIRO H 4460–01 , 37.2 mm SL, east of Mallacoota , Victoria, 37° 36'S, 149° 52'E, 78–80 m, 27 Nov. 1996 ; NMV A 29408–001 , 36.2 mm SL, off Cape Conran, Bass Strait , Victoria, 38° 00'S, 149° 09'E, 118 m, 22 Sep. 1983 .

Diagnosis. Member of the genus Pezichthys with a bold colour pattern, long dermal spinules, a humped nape and the posterior extension of the first dorsal-fin membrane is very short (i.e. interdorsal distance long). It also differs from its congeners in a combination of the following characters: esca small, 19–21% of illicium length; illicium very slender, without dermal spinules, its length 16–20% SL, 2.5–3.1 times in head length in adults; head length 4.9–6.2 times snout length; snout long, length 8–10% SL; eye 6.2–7.7 times in head length; body moderately robust, maximum width 30–38% SL; interorbital width 8–11% SL; scale bases subcircular with relatively long bifurcate spinules (except for those closely associated with pores of the acoustico-lateralis system); spinules variable in length over body; dorsal-fin elements with spinules, membranes of fins mostly naked; first dorsal-fin base length 18–20% SL; second dorsal-fin rays 15–16 (usually 16), fin base 55–63% SL; length of second dorsal-fin spine 1.4–1.9 times length of longest ray of second dorsal fin; anal-fin rays 7–9; upper body variegated, lacking dark spots or streaks; caudal fin not covered with fine spots.

Description. D1 2 (2, n= 6 paratypes); D2 15 (15–16, mainly 16); A 8 (7–9, rarely 7); Pc 7 (7); Pv i, 4 (i, 4); C 1 (1) + 6 (6–7) + 2 (1–2) = 9 (9); Vt 9 (9) + 12 (12) = 21 (21).

Body moderately robust, weakly compressed; upper anterior profile slightly convex, not elevated, dorsal margin of eye well below top of head; not triangular when viewed anteriorly; nape humped slightly; anterior ventral profile strongly convex; abdomen globose; caudal peduncle elongate, length 8.6 (6.8–10.6)% SL. Head length 54 (50–52)% SL; snout short, 6.0 (4.9–6.2) times in head; eye very small, 7.7 (6.2–7.1) times in head length; gill opening small, aperture smaller than pupil, located slightly above and behind insertion of pectoral fin; nostrils very small, openings not protruding; posterior opening posterodorsal to anterior opening, separated slightly from orbit. Mouth small, terminal, moderately protractile; upper jaw oblique, 4.5 (3.6–4.3) in head; upper lip fleshy; lower lip fleshy medially, connected laterally to lower jaw by fleshy dorsoventrally flattened fold; angle of jaw partly recessing into groove, situated below middle of eye; tongue well developed, rounded apically. Teeth minute, villiform, in long broad bands in both jaws; vomer edentate.

Skin rather thick, covered with bifid, spinulose scales; no separate wart-like patches of skin; small dermal flap present on mid-arm of pectoral-fin; flap tentacular, strongly compressed, sub-equal in size to gill opening; several long, delicate, tentacular dermal flaps on body and leading elements of dorsal fins (size and position of flaps variable). Body scales close-set, not arranged in defined rows, distributed over entire body; scale bases embedded but not within raised mound of thickened skin. Spinules relatively long, erect, well exposed, bifurcating well above skin (spines of each spinule subequal to or slightly longer than distance between their tips); connected by integument when undamaged; much smaller on belly, semi-erect; present on orbital membrane; scale bases usually subcircular with weakly irregular margins, their width slightly shorter or subequal to spinule length; spinules arising from near middle of scale base. First dorsal-fin spines and leading ray of second dorsal fin densely covered with small spinulose scales; similar spinules in rows along anterolateral margins of other rays of second dorsal fin; 1–2 rows of small spinules usually on upper surfaces of pectoral, pelvic and caudal-fin rays; anal fin with or without spinulose scales; fin membranes mostly naked. Illicium with thin, naked cutaneous sheath; its base spinulose. Scales of acoustico-lateralis system bicuspid, not particularly obvious from main spinules; scales widely separated and arranged in barely discernable rows; pronounced at chin apex, otherwise indistinct on head.

Illicium terminal on snout, very slender; length 2.5–3.1 times in head, 1.7–2.2 times in length of second dorsal-fin spine; apex of esca just short of, or reaching to, base of third dorsal-fin spine when fin depressed; partly retractable into shallow groove on either side of first dorsal fin; esca small, not bulbous (a small fleshy expansion in holotype but with multiple short filamentous branches in some paratypes), 5–6 times in length of illicium; illicial base bulbous. First dorsal fin rather small; second dorsal-fin spine almost confluent with base of illicium, longer than third spine; fin membrane thick, greatly expanded basally around each spine, posterior extension short; membrane terminating above to just behind level of insertion of pelvic fin; anterior elements of both fins strongly recurved; first dorsal-fin base 2.9 (2.9–3.4) times in second dorsal-fin base. Second dorsal fin low, weakly incised, anterior and penultimate posterior rays longest; rays simple; fin base moderately elongate, 59 (55–63)% SL; longest ray of second dorsal fin 1.5 (1.4–1.9) times in longest dorsalfin spine; basal membrane relatively thick, concealing bases of all fin rays, covering almost a third of anterior fin rays. Anal fin short, rays fleshy, moderately incised; penultimate posterior rays longest; anal-fin base 2.3 (2.0–2.4) times in second dorsal-fin base. Pectoral fin weakly arm-like, radials moderately elongate, barely extending beyond gill opening; fin rays digitiform, slender, membranes deeply incised, not increasingly so posteriorly, tips flexible, slightly flattened (often recurved distally). Pelvic fin short; rays digitiform, slender, deeply incised; anterior spine short, embedded and indistinct; fin located on ventral surface, usually directed ventrolaterally, base aligned horizontally; interpelvic space broad, almost flat. Caudal fin deep, narrowly rounded; length 3.6 (3.4–4.6) times caudal peduncle depth.

*Distance from the base of the third dorsal-fin spine to the origin of the second dorsal fin.

Coloration. In life: Body of holotype pale brownish pink with lighter and darker floral blotches; broad pale areas over eye (extending from first dorsal-fin base in an arc to pectoral-fin base) and as a saddle below rays 3–5 of second dorsal fin; a large, darker brown blotch on cheek and a broad, diagonal, brown and silvery white band between these pale areas (extending from region of nape and anterior portion of soft dorsal fin); tail with brown and silvery white mottled pattern; eye bluish black; gill opening pale brown, strongly demarcated. Illicium with faint brown and whitish bands. First dorsal fin pink or translucent basally, with darker brownish areas distally (speckled in some paratypes); margin of membrane between rays brownish. Second dorsal fin with 3–4 horizontal rows of small, brownish spots; spots diffuse-edged, situated mainly on fin rays, densest on posterior portion of fin; margin of fin dark. Caudal fin with a narrow, dark, vertical band at its base, and a submarginal, vertical row of large brownish black botches (centred on fin rays and appearing as a continuous band when fin collapsed); rest of fin translucent pink, basal rays yellowish in holotype only. Anal fin yellowish anteriorly (white in paratypes), with broad diagonal dark bar posteriorly; dark spots confined to posterior third of fin (except in paratype CSIRO H 4448–02). Pectoral arm blotched, similar to dark markings on body; distal portion of fin and pelvic fin yellowish (whitish in paratypes).

In preservative: Body and fin markings faded, brownish and white.

Size. Attains at least 45.7 mm SL (ca. 60 mm TL); smallest specimen examined 30.1 mm SL. Two paratypes (CSIRO H 4460–01, 37.2 mm SL and NMV A 29408–001, 36.2 mm SL) gravid, egg capsule diameter ranges from ca. 1.4–2.0 mm.

Distribution. Demersal, off southeastern Australia; from off Bermagui, southern New South Wales (36° 22′S, 150° 12′E), to off Cape Conran, eastern Bass Strait, Victoria (38° 00′S, 149° 09′E). Collected in depths of 74– 121 m.

Etymology. A combination of the Latin amplus (large) and spina (spine, thorn) in allusion to the dense covering of long dermal spinules over its skin. Proposed vernacular name: Cockatoo Handfish.

Comparisons. Comparisons of this species with other members of the genus are provided in the following treatments.

Remarks. Pezichthys amplispinus , which has long, erect dermal spinules and rougher skin than other handfishes, also has an atypically tall, short-based first dorsal fin resembling the crest of a cockatoo. It may have special habitat requirements given its apparent rarity and narrow distributional range. It was only caught in a small area off southeastern Australia despite broad survey coverage across southern Australia using appropriate fishing methods.

Figures

FIGURE 2. Illustrations of the illicium and esca of: A. Brachionichthys australis, CSIRO H 4114–07, 55.8 mm SL; B. Brachionichthys hirsutus, CSIRO T 7, 78.9 mm SL; C. Brachiopsilus dianthus sp. nov., CSIRO H 4995–01, holotype, 99.5 mm SL; D. Brachiopsilus dossenus sp. nov., NMV A 29405–002, holotype, 65.0 mm SL; E. Brachiopsilus ziebelli sp. nov., CSIRO T 1993–01, holotype, 101.5 mm SL; F. Pezichthys amplispinus sp. nov., CSIRO H 4460–01, 37.2 mm SL; G. Pezichthys compressus sp. nov., CSIRO H 4447–01, holotype, 42.4 mm SL; H. Pezichthys eltanini sp. nov., LACM 11516–1, holotype, 30.0 mm SL; I. Pezichthys macropinnis sp. nov., CSIRO H 5317–02, holotype, 20.5 mm SL; J. Pezichthys nigrocilium sp. nov., CSIRO H 6154–01, holotype, 40.8 mm SL; K. Sympterichthys moultoni sp. nov., CSIRO H 3773–03, holotype, 45.1 mm SL; L. Thymichthys politus, CSIRO H 782–01, 67.3 mm SL; M. Thymichthys verrucosus (tasselled morph), CSIRO T 5, 51.3 mm SL; and N. Thymichthys verrucosus (eastern form) CSIRO H 3781– 01, 63.5 mm SL.

FIGURE 3. Skin morphology of: A. Brachionichthys australis, CSIRO H 4451–02 (x40); B. Brachionichthys hirsutus, TMH D 640 (x40); C. Brachiopsilus dianthus sp. nov., CSIRO H 4995–01, holotype (x20); D. Brachiopsilus dossenus sp. nov., NMV 29405–002, holotype (x20); E. Brachiopsilus ziebelli sp. nov., CSIRO T 1993–01, holotype (x25); F. Pezichthys amplispinus sp. nov., CSIRO H 4448–01, holotype (x50). All images orientated as a view of mid-upper body on left side (i.e. anterior part to left).