Ophiocara porocephala (Valenciennes, 1837)

Keith, Philippe & Mennesson, Marion I., 2021, Review of Ophiocara (Teleostei: Butidae) from Indo-Pacific Islands, Cybium 45 (2), pp. 89-108 : 102-104

Ophiocara porocephala (Valenciennes, 1837)

( Figs 2-3 , 6 , 8 ; Tabs II-III)

Eleotris madagascariensis, Valenciennes in Cuvier & Valenciennes, 1837, Madagascar, Goudot coll.; syntypes: MNHN-IC-A-2709 (2).

Eleotris porocephaloides Bleeker, 1854 , Priaman, Sumatra, Indonesia, Bleeker coll.; holotype (unique): RMNH 6198 .

Eleotris limosus Smith, 1936 , Isipingo lagoon, South Africa; holotype (unique): SAIAB 95 .

Eleotris litoralis Day, 1876 , Andaman Islands, east of Bay of Bengal; Holotype (unique): ZSI 111 (lost) [Considered by Kottelat (2013) to be a synonym of O. ophicephalus . As the type locality is Andaman, the species should be O. porocephala , which is distributed in Indian Ocean].

NB: Eleotris scintillans Blyth, 1860 from Andaman is generally considered to be a synonym of Ophiocara ophicephalus ( Kottelat, 2013) , but Day (1869) mentioned on the Blyth specimen ‘small scales… and a black ocellus on the upper part of the caudal fin’, and he added later ( Day, 1876) that the specimen has 42 lateral scales. These data suggest that E. scintillans is probably not an Ophiocara but could be an Incara (D. Hoese, pers. comm.), which is very similar to Ophiocara , but has smaller (and more) scales than Ophiocara (never more than 39 LS in Ophiocara ). We list here this species as incertae sedis.

Material examined

As in the syntypes series of E. porocephala , two species are represented (see Clade B and C of our trees) to avoid confusion, according to ICZN (1999: art. 74.1) we here designate a lectotype among the 5 syntypes MNHN-IC-A-1573 from Seychelles Islands , which become the unique type locality of the species .

Lectotype. – MNHN-IC-2020-0477, male, 98 mm SL; Seychelles Islands, Dussumier coll. (extracted from MNHN-IC-A-1573).

Paralectotypes. – MNHN-IC-A-1573 (4), 93-110 mm SL; Seychelles Islands, Dussumier coll.

Others. – MNHN-IC-A-2709, syntypes of Eleotris madagascariensis, Val. in Cuvier & Valenciennes, 1837; 2 females (195-203 mm SL) , Madagascar, Goudot coll. SAIAB 95, holotype (unique), of Eleotris limosus Smith, 1936 ; 198 mm SL, Isipingo lagoon, South Africa; not seen, data from D. Hoese . RMNH 6198, holotype (unique) of Eleotris porocephaloides Bleeker, 1854 ; Priaman, Sumatra, Indonesia, Bleeker coll . MNHN-IC-1960-0223, female (198 mm SL), Ivolina, Madagascar, Kiener coll. MNHN-IC-2020-0177, male (127.4 mm SL), Antalaviana, Madagascar, May 2010, Diamsoi coll.; tag 12653. MNHN-IC-2020-0178, 1 male, 2 females (70-130 mm SL), Dembéni, st 026, Mayotte, Comoros, 12 Aug. 2019, Valade et al. coll.; tags 14512, 14513, 14514. MNHN-IC-2020-0480, Tahiti plage, Mayotte, Comoros, 16 May 2006, Keith & Arda coll.; tags 12531, 12532, 12534. MNHN-IC-2006-0603, female (117 mm SL), Mjawatché, Mohéli, Comoros, 31 Oct. 2005, Keith & Marquet coll. MNHN-IC-2020-0179, female (66 mm SL), Gorre, Mahé, Seychelles, 2 Feb. 2020, Mennesson, Keith & Henriette coll.; tag 12589. MNHN-IC-2020-0180, male (60 mm SL), Anse petite court, Praslin, Seychelles, 23 Feb. 2020, Mennesson, Keith & Henriette coll.; tag 12733. MNHN-IC-2020-0181, 2 males (of 8) (69-93 mm SL), NouvelleDécouverte, Praslin, Seychelles, 8 Oct. 2003, Keith & Arda coll.; tags 12523, 12524.

Diagnosis

The species usually has 35-37 lateral scales, 21-24 predorsal scales, 9-10 zigzag scales and the jaw length is 14-16% SL.

Description

Below, the lectotype counts are given first, followed in brackets, if different, by the other specimens counts. The scale counts are given in table II and selected morphometrics in table III.

The body is more ovoid than elongated. The body depth at anus is 22 (19-26% SL), at first dorsal fin 21 (20-26% SL), and the caudal peduncle depth is 17 (14-17% SL). Predorsal length 44 (42-46% SL) and preanal length 68 (61-69% SL). Size: up to 27 cm SL.

The head 37 (33-39% SL) is depressed, the snout is convex. The anterior nostrils are long, reaching lower margin of upper lip. The mouth and jaw length 15 (14-16% SL) are large with inwardly curved teeth set on both jaws and larger on outer row of upper jaw. Posterior end of maxillary extending below 1/2 or 2/3 of posterior margin of eye. Eye diameter 6 (6-8% SL) and interorbital length 13 (11-14% SL). Usually 26 vertebrae. Gill opening extending beyond the posterior end of urohyal. Gill rakers 12-13.

Dorsal fins VI-I,8 with no filamentous rays. The first dorsal fin is with second, third and fourth rays longer. Anal fin I,7 directly opposite to the second dorsal fin. The caudal fin is with 14-15 branched rays and its posterior margin is rounded. Pelvic fins separate, I,5. Pectoral fins 15, with the posterior margin rounded. Lateral scales 35 (35-37), with ctenoid scales on flanks and caudal peduncle. Cycloid scales from snout to top of head and anterior part of D1, on operculum, on base of pectoral fins and on belly extending to anus. Scales of top of head and back bigger than those of belly. Scales in transverse back series 13 (12-13), in transverse forward 17 (16-18), in predorsal 22 (21-24) and in zigzag usually 9 (9-10) (1 specimen with 8).

Cephalic sensory pore system as described by Akihito and Meguro (1974) and Akihito (1986) with oculoscapular canal nasal to post-temporal with the pores A to L except for G; preopercular canal long with the pores M to Q; oculoscapular canal grooves on nasal, frontal, pterotic and post-temporal; inner side of oculoscapular canal on frontal walled continuously from C to F; preopercular canal groove long. Head sensory papillae as described by Akihito and Meguro (1974) and Akihito et al. (1988).

Males with a rounded/elongated urogenital papilla with distal tip rounded. The females have rectangular or chaliceshaped bulbous urogenital papilla with crenulated outer edges around distal opening.

Colour in preservation

Background of body brown on the back. The flanks are brownish with some greyish patches. Belly greyish. Top of head brownish, as lateral parts; with sometimes 2 or 3 dark brown stripes radiating from the eye to the cheeks and operculum. The first and second dorsal fins are greyish with several rows of aligned dark spots along rays. The pelvic, pectoral and anal fins are greyish and without spots.

Colour in life

Adults. – Most common pattern similar for male and female. Background of body dark grey to black on the back. Flanks greyish to black. Four to five light brown or whitish interrupted bands on the flanks, sometimes not very visible. The first one (if exists) below the first dorsal fin, the second one from the anterior part of the second dorsal fin to the medium part of belly, the third one from the posterior part of the second dorsal fin to the anterior part of the anal fin, the fourth around the caudal peduncle, and the fifth at the hypural base. Top of head brownish, with sometimes whitish parts between eyes and on nose. Lateral part brown with 3 dark brown stripes and sometimes a white one radiating from the eye to the cheeks and operculum. Isthmus and belly greyish. Bigger specimens mostly dark grey ( Fig. 8A ), without any white bands or white spots on the flanks, head or hypural base (white marks less marked on old specimens). The first and second dorsal fins are greyish with several rows of aligned dark spots along rays. The pelvic, pectoral and anal fins are grey. The anal and caudal fins have a light yellow distal part ( Fig. 8A, B ).

Juveniles. – Background of body greyish to black on the back. Flanks greyish to black. Five vertical white bands on the flanks, two well marked flashy continuous bands; the first one, from the anterior part of the second dorsal fin to the medium part of belly, the second one, around the caudal peduncle; and three interrupted bands, the first one below the first dorsal fin, the second one from the posterior part of the second dorsal fin to the anterior part of the anal fin, and the third one with three white spots on hypural base. Top of head brownish, with whitish parts between eyes and on nose. Lateral part greyish with 3 dark brown stripes and two greyish radiating from the eye to the cheeks and operculum. A gold spot on operculum. Isthmus and belly whitish to greyish. The first and second dorsal fins are greyish with 4-5 rows of dark aligned spots along rays. The pelvic, pectoral and anal fins are translucent. The anal and caudal fins have a light yellow distal part ( Fig. 8C ).

Ecology

The species occurs mainly in the vegetation or under stones, roots or under leaf litter in the lower parts of rivers and ponds, from tidal influence to 15 m high in altitude, with sandy, muddy or gravel bottoms. It is carnivorous and feeds on crustaceans, molluscs and fish. It is particularly abundant in Seychelles Islands where it dominates the fish communities in rivers and ponds ( Keith et al., 2006).

Distribution

Ophiocara porocephala is known from the Indian Ocean from South Africa and Mozambique to Madagascar, Comoros, Seychelles, Andaman Islands and Indian Ocean coast of Sunda Islands and Sumatra ( Indonesia) ( Fig. 6 ).

Comparison

Ophiocara porocephala differs from the other species sequenced by having a significant percentage of divergence in COI gene (8.2%) (Suppl. data). Moreover, it differs from O. ophicephalus by a combination of characters including more scales in lateral series (35-37 vs 32-34), transverse backward series (12-13 vs 11-12) and in zigzag series (usually 9-10 vs usually 8), and a smaller jaw length (14-16 vs 16-17% SL). The ‘silver dotted pattern’ ( Fig. 7B ), known for O. ophicephalus , is unknown for O. porocephala , and the juveniles have usually more vertical interrupted white bands (3) on the flanks than O. ophicephalus (1). O. porocephala differs from O. cantoris by fewer scales in lateral series (35- 37 vs 37-39), transverse forward series (16-18 vs 18-20) and predorsal series (21-24 vs 25-27).

Figures

Figure 2. – Bayesian tree of the cytochrome c oxidase subunit (COI; 446 bp) for sequenced specimens of Ophiocara. Numbers at each node represent posterior probabilities.

Figure 3. – Barcoding NJ K2P trees of the cytochrome c oxidase subunit for sequenced specimens of Ophiocara including three syntypes from MNHN collection; Eleotris porocephala Valenciennes, 1837 from New Ireland (Papua New Guinea) (MNHN-IC-A-1574) and from Seychelles (MNHN-IC-A-1573), and E. madagascariensis Valenciennes, 1837 (MNHN-IC-A-2709). Numbers at each node represent bootstrap values. For all trees, MNHN syntypes are in bold. In tree (A) [199 bp], the three specimens from the Museum & Art Gallery of the Northern Territory (NTM,Australia) are highlighted with a star; Tree (B) [110 bp]; Tree (C) [106 bp].

Figure 6. – Distribution of Ophiocara species.

Figure 7. – A: Ophiocara ophicephalus, male, New Caledonia (Photo N. Charpin); B: Ophiocara ophicephalus, male, ‘silver dotted pattern’, New Caledonia (Photo L. Taillebois); C: Ophiocara ophicephalus, juvenile, New Caledonia (Photo E. Vigneux).

Figure 8. – A: Ophiocara porocephala, male, Seychelles (Photo J.F. Perrin); B: Ophiocara porocephala, in vivo, Mahé, Seychelles (Photo P. Keith); C: Ophiocara porocephala, juvenile, Mayotte, Comoros (Photo P. Keith).