Forsterygion malcolmi Hardy, 1987

Jawad, Laith A., 2008, Second revision of the New Zealand triplefin genus Forsterygion Whitley and Phillips, 1939 (Pisces: Tripterygiidae), Journal of Natural History 42 (47 - 48), pp. 2943-2989 : 2973-2974

Forsterygion malcolmi Hardy, 1987

Banded triplefin (Mottled triplefin)

Forsterygion sp. Thompson 1981, p. 243, Fig. on 244.

Tripterygion sp. Ayling 1982, p. 280, pl. 38; Paulin and Stewart 1985, p. 51; Roberts et al. 1986, p. 358.

Diagnosis

A species of Forsterygion with the following set of characters: Body elongated, laterally compressed posteriorly; mouth strongly angled upward; notched scales absent; short, distally complex gill rakers, body yellow with a broad, black stripe extending along upper side of body. Dorsal fin formula V-0N-0-1-0-1 (40). Six procurrent rays in upper lobe, ten in lower lobe; in upper caudal lobe, one procurrent ray between upper lobe and posterior epural, four rays opposite epurals, one anterior first epural; in lower lobe, one procurrent ray between lower lobe and haemal spine of second preural vertebra, four opposite haemal spine of second preural vertebra, five anterior to haemal spine of second preural vertebra.

Description

The following counts and proportions (given as times in standard length unless otherwise stated) are based on 45 non-types, 38–96mm SL. The description of F. malcolmi differs from that of F. varium in the following characters: snout steeply angled, angle 65–73 °.

Head length 3.9–4.2; predorsal length 4.2–5.1; preanal length 2.0–2.3; peduncle length 10.9–11.8; peduncle depth 12.6–13.9; pectoral fin length 3.4–3.7; eye diameter 2.4–2.5 in HL; upper jaw length 2.9–3.1 in HL; snout length 2.9–3.2 in HL.

First dorsal fin spines V–VI; second dorsal fin spines XXII–XXVI; third dorsal fin rays 12–14; pectoral fin rays 18–20; anal fin with 2 spines and 26–29 soft rays. Discontinuous lateral line with 29–37 tubular scales, 0–10 notched scales, when present, extending intermittently from caudal fin base to below distal end of tubular scale row, separated from latter by 1–2 scales. Total vertebral number 43–47.

Head sensory canals. Supratemporal canal with few small sensory pores. Ventral part of the preoperculo-mandibular canal with seven pores, four at lower corner of preoperculum, two at tip of upper jaw and one at lower jaw symphysis.

Squamation. Eight to nine scale rows between anterior end of second dorsal fin and lateral line. No scales between second and third dorsal fins. Seventeen to eighteen scales around caudal peduncle. Number of radii in different body regions ranging between 9 and 16. Ctenii with similar length in different body regions. Two separated groups of ctenii on posterior edge of lateral line scales. Denticles curved. Oval focus with smooth area and a complete circulus.

Osteology. Post-temporal serrated, exposed posteriorly. Small, club-shaped, straight posterior edge basihyal. Third basibranchial chisel shape, not reaching fourth basibranchial. Gill rakers oppositely arranged. Phalanges at lateral end of first epibranchial extended at both anterior and posterior sides. First epibranchial broader than second. Urohyal irregular with several indentions (lateral view), with upward raised lateral wings. Dorsal fin formula V-0N-0-1-0-1 (40). Lower hypural with straight edges. Short, blunt neural spine of second preural vertebra. Two different length epurals. Fourteen soft rays in caudal fin, two unbranched and five branched (non multibranched) rays in upper and lower caudal lobes. One pterygiophore between second and third dorsal fins. Six procurrent rays in upper caudal lobe, ten in lower lobe; in upper lobe, one procurrent ray between upper lobe and posterior epural, four rays opposite epurals, one anterior first epural; in lower lobe, one procurrent ray between lower lobe and haemal spine of second preural vertebra, four opposite haemal spine of second preural vertebra, five anterior to haemal spine of second preural vertebra.

Otolith. Lobed anteriorly, irregular posteriorly ventral margin. Crista superior absent. Pointed rostrum. Antirostrum broad.

Colour. Head olive-brown, usually with light vertical stripes on cheek passing through jaws and running through preoperculum/opercular region. Greyish flecks separate stripes. Ventral side of head yellow with dense grey fine spots. Iris orange, sometimes with dark brown spots on upper posterior corner.

Six vertical bands across body, usually reddish-orange or reddish-brown, separated by thin irregular white bands, three anterior most running anterodorsally onto second dorsal fin. Reddish-brown smudges separate the bands at dorsal fin base. First dorsal fin greyish proximally, becomes pinkish with greyish flecks. Third dorsal fin reddish proximally, with greyish margin. Breeding males blackish, particularly on fins, with white anal fin margin.

Size. 22mm SL.

Distribution

Widely distributed throughout New Zealand, from the Three Kings Islands to Stewart Island including the Chatham Islands. Abundant on rocky reefs from 10 to 25m , recorded from 2 to 33m.

Material examined

Museum specimens (n 545): NMNZ P. 33542, 5, 74–86mm SL, Foul Point, Abel Tasman Park , Golden Bay , 3 Dec 1993 . University of Auckland specimens: 4, 38.8– 45.2mm SL, Ulva Island, Stewart Island , 30 Jan 1998 ; 9, 42– 96mm SL, Mokohinau Islands , 18 Feb 1998 ; 10, 52– 71mm SL, Great Barrier Island , 15 Oct 1997 ; 2, 72– 74mm SL, Nelson Island, Great Barrier Island , 12 Sep 1998 ; 9, 71– 82mm SL, Ti Point , 21 Oct 1997 ; 6, 48– 116mm SL, Breaker Bay , Wellington, 9 Feb 1998 .