Island Longfin, Plesiops insularis Mooi & Randall 1991


An Island Longfin, Plesiops insularis, New Caledonia . Source: Rick Winterbottom. License: CC BY Attribution-NonCommercial-ShareAlike 3.0

Summary:
A pale to dark longfin with a narrow blue margin and a broader blue submarginal band on the dorsal and anal fins, a blue ring around the eye, and often a large yellow patch on the cheek and gill cover.

Cite this page as:
Bray, D.J. 2020, Plesiops insularis in Fishes of Australia, accessed 30 Mar 2024, https://fishesofaustralia.net.au/home/species/4606

Island Longfin, Plesiops insularis Mooi & Randall 1991

More Info


Distribution

Lord Howe Island, Norfolk Island, Elizabeth and Middleton reefs in the Tasman Sea. Elsewhere the species occurs in New Caledonia, the Chesterfield Bank in the Coral Sea and Tonga.
Inhabits tide pools, crevices and holes in coral and rocky reefs; rarely seen by divers.

Features

Dorsal fin XII-XIII,6-8, 5th-6th dorsal-fin rays longest; Anal fin III, 7-9, 5th-7th ray longest; Pectoral fin 21-24, pectoral fins with ventral-most rays free of  membrane to form a fringe; Pelvic fin I,4, first pelvic-fin ray elongate but relatively short for Plesiops, and notice-  ably thickened, first ray extending to base of 3rd anal-fin ray; Principal caudal-fin rays (upper + lower) 8-10 + 8-9); Procurrent caudal-fin rays (upper + lower) 5-7 + 2-7); Gill rakers, upper + lower 4-6 + 10-19, total 15-24.

Colour

Pale spots and stripes absent on body, spots absent from operculum, preoperculum and body scales; dorsal-fin spine tips only very slightly paler than remaining fin; scales on base of pectoral fin with a dark spot, sometimes obscure or absent.
Holotype (from image) body and base of median fins dark sepia, body lighter anteroventrally near pelvic-fin base; posterior caudal peduncle with a dorsal and an elongate ventral spot half-way between lower lateral line and procurrent caudal-fin rays, but barely discernible; spot on pectoral-fin base obscure; head dark sepia dorsally; 2 obscure dark blotches behind eye, one  posterodorsal and the other posteroventral; a more obvious stripe running from the midventral orbit just above  maxilla, another from posterior end of maxilla to preopercular margin; cheek lighter, the opercle, subopercle,  interopercle, preopercle, and part of branchiostegal membranes yellow to ochre; iris of eye blue peripherally and  orange-red around pupil; dorsal fin with a bright blue stripe from base of 1st spine, angling slowly upward until  midlength of 12th spine where horizontal to end at 5th soft ray; above this a red-brown stripe following same  pattern; tips of spines gray, rest of soft portion of dorsal fin dark sepia with a white marginal stripe; anal fin with similar pattern to dorsal, but blue from base of 3rd spine back to 7th ray, red-brown only to 5th ray; a white marginal stripe on soft portion of anal fin; caudal fin dark on  central rays with yellowish on dorsal and ventral third of fin; pectoral fins dark; pelvic fins pale with yellowish tip on elongate first ray. 
Other specimens, colour can be similar to above or quite different. Body generally dark with little or no colour except for eye, as above, and a pale reddish median stripe on dorsal-fin spines and membranes; tips of dorsal-fin spines dark; proximal half or two-thirds of rays and membranes of dorsal, anal, and caudal fins pale; posterior caudal peduncle with 2 elongate spots, each mid-way between lower lateral line and procurrent caudal-fin rays.

Biology

The male parent guards the developing eggs.

Etymology

The specific name insularis is from the Latin word meaning 'of islands', in reference to the present distribution of the species, in the islands of the New Caledonia Basin region.

Species Citation

Plesiops insularis Mooi & Randall 1991, Copeia 1991(2): 379, pl. 1B-C, figs 3-4, 5A, A, 7-8. Type locality: reef west of Mt Lidgbird, Lord Howe Island, New South Wales.

Author

Bray, D.J. 2020

Resources

Atlas of Living Australia

Island Longfin, Plesiops insularis Mooi & Randall 1991

References


Allen, G.R., Hoese, D.F., Paxton, J.R., Randall, J.E., Russell, B.C., Starck, W.A., Talbot, F.H. & Whitley, G.P. 1976. Annotated checklist of the fishes of Lord Howe Island. Records of the Australian Museum 30(15): 365-454 figs 1-2 (as Plesiops sp.)

Francis, M. 1993. Checklist of the coastal fishes of Lord Howe, Norfolk, and Kermadec Islands, southwest Pacific Ocean. Pacific Science 47(2): 136-170 figs 1-2 

Kuiter, R.H. 2004. Basslets, Hamlets and their relatives. A comprehensive guide to selected Serranidae and Plesiopidae. Chorleywood, UK : TMC Publishing 1, 216 pp. 

Mooi, R.D. 1995. Revision, phylogeny, and discussion of biology and biogeography of the fish genus Plesiops (Perciformes: Plesiopidae). Royal Ontario Museum Life Sciences Contributions 159: 1-107 See ref at BHL

Mooi, R.D. 1999. Families Plesiopidae, Notograptidae. pp. 2586-2587 in Carpenter, K.E. & Niem, T.H. (eds). The Living Marine Resources of the Western Central Pacific. FAO Species Identification Guide for Fisheries Purposes. Rome : FAO Vol. 4 pp. 2069-2790. 

Mooi, R.D. & Randall, J.E. 1991. Three new species of the genus Plesiops (Teleostei : Plesiopidae) from tropical Australian and adjacent seas. Copeia 1991(2): 373-386 

Ramsay, E.P. 1888. Report on the Museum's expedition to Lord Howe Island. Annual Report of the Australian Museum 1887: 1-34 (as Plesiops nigricans)

Randall, J.E. 2005. Reef and shore fishes of the South Pacific. New Caledonia to Tahiti and the Pitcairn Islands. Honolulu : University of Hawaii Press 707 pp.

Randall, J.E., Allen, G.R. & Steene, R. 1997. Fishes of the Great Barrier Reef and Coral Sea. Bathurst : Crawford House Press 557 pp. figs.

Quick Facts


CAAB Code:37316021

Depth:0-25 m

Habitat:Reef associated

Max Size:10 cm SL

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Species Maps

CAAB distribution map