A New Species of Lepadichthys from the Central South Pacific and Comments on the Taxonomic Status of Lepadichthys springeri Briggs, 2001 (Gobiesocidae)
Lepadichthys conwayi, new species, is described on the basis of 42 specimens (13.0–42.0 mm in standard length [SL]) collected from the central South Pacific and characterized by the following combination of characters: head sensory canal pores well developed, including 2 nasal, lacrimal and postorbital, and 3 preopercular pores; 13–16 (modally 15, rarely 16) dorsal-fin rays; 11–14 (12, rarely 14) anal-fin rays; 27–30 (28) pectoral-fin rays; 8 or 9 (9), 8–11 (9), and 8–11 (9) gill rakers on first to third arches, respectively; upper end of gill membrane level with base of 7th to 10th (usually 9th) pectoral-fin ray in lateral view; disc length and width 15.0–17.1 (mean 16.0) and 11.1–16.1 (13.9) % SL, respectively, disc length plus disc width 27.8–33.2 (30.0) % SL; dorsal and anal fins with very weak membranous connections to (rarely separated from) caudal fin, posteriormost points of membranes usually just short of or just reaching vertical through caudal-fin base, otherwise very slightly beyond fin base; dorsal- and anal-caudal membrane lengths 3.4–7.1 (4.8) and 3.0–6.0 (4.8) % of caudal-fin length, respectively; black stripe on snout tip through eye to posterior region of head. In addition, examination of the type specimens of Lepadichthys springeriBriggs, 2001 revealed them to be conspecific with L. misakius (Tanaka, 1908), a valid species recently resurrected from the synonymy of L. frenatus Waite, 1904. Accordingly, L. springeri is regarded as a junior synonym of L. misakius.
Preserved specimens of Lepadichthys conwayi, new species. (A–C) USNM 423325, holotype, 39.3 mm SL, Raivavae Island, Austral Islands; (D) USNM 430732, 1 of 3 paratypes, 31.2 mm SL, Rimatara Island, Austral Islands; (E) BPBM 16921, 1 of 3 paratypes, 29.1 mm SL, Down Rope, Pitcairn Island, Pitcairn Islands; (F) KAUM-I. 139792, paratype, 26.0 mm SL, same as holotype; (G) KAUM-I. 139318, paratype, 24.6 mm SL, Oeno Island, Pitcairn Islands; (H) USNM 430856, 1 of 3 paratypes, 20.6 mm SL, Tubuai Island, Austral Islands; (I) ROM 38104, paratype, 13.0 mm SL, Avarua, Rarotonga Island, Cook Islands. (A, D–I) Lateral views. (B) Dorsal view. (C) Ventral view.
Fresh coloration of Lepadichthys conwayi, new species. (A) USNM 423325, holotype, 39.3 mm SL, Raivavae Island, Austral Islands; (B) USNM 404728, paratype, 33.2 mm SL, Totegegie Island, Gambier Islands; (C) USNM 422862, paratype, 26.4 mm SL, same as holotype; (D) USNM 423420, paratype, 37.8 mm SL, Tubuai Island, Austral Islands; (E) USNM 423414, paratype, 31.3 mm SL, same as USNM 423420. (A–C) Lateral views. (D) Dorsal view. (E) Ventral view. Photos by J. Williams.
Head sensory canal pores of Lepadichthys conwayi, new species. Sketches based on BPBM 38419, 36.1 mm SL. Scale bar = 1 mm. Abbreviations: AN and PN, anterior and posterior nostrils, respectively; LC, lacrimal canal pores; NC, nasal canal pores; PO, postorbital canal pores; PR, preopercular canal pores.
Relationships of (A) disc length, (B) disc width, and (C) disc length plus disc width (as % of standard length) to standard length (mm) in Lepadichthys conwayi, new species (red circles), Lepadichthys ctenion (yellow inverted triangles), and Lepadichthys misakius (blue triangles). Abbreviations: H, holotype; HS and PS, holotype and paratype of Lepadichthys springeri, respectively.
Posterior portions of dorsal and anal fins in Lepadichthys conwayi, new species (A–C, in red frame); Lepadichthys erythraeus (D–F, in green frame); and Lepadichthys misakius (G–I, in blue frame). (A) USNM 423325, holotype, 39.3 mm SL; (B) KAUM-I. 139791, paratype, 30.3 mm SL; (C) USNM 430773, 1 of 11 paratypes, 28.2 mm SL; (D) USNM 424451, 1 of 17 specimens, 30.7 mm SL; (E) USNM 424447, 1 of 10 specimens, 25.4 mm SL; (F) USNM 424450, 1 of 14 specimens, 18.2 mm SL; (G) KAUM-I. 11266, 49.1 mm SL; (H) KAUM-I. 17580, 38.5 mm SL; (I) CMNH-ZF 6309, 23.3 mm SL. Arrowheads indicate posteriormost points of dorsal- and anal-fin membranes associated with caudal fin. Broken lines indicate vertical through caudal-fin base.
Relationships of (A, C) dorsal-caudal membrane length and (B, D) anal-caudal membrane length (as % of caudal-fin length [CL]) to standard length (mm) in Lepadichthys conwayi, new species (red circles); Lepadichthys erythraeus (green squares); and Lepadichthys misakius (blue triangles). Other abbreviations as in Figure 4.
Relationships of number of papillae rows on disc regions A (A) and B (B) to standard length (mm) in Lepadichthys conwayi, new species (red circles) and cyanine stained pelvic discs (C, D) of the species. Open symbols indicate specimens lacking disc papillae patch (red dots in C) on disc region A.
Distributional map of Lepadichthys conwayi, new species (circles). Map also indicates collection locality of type specimens of Lepadichthys springeri (triangles). Arrowheads indicate type locality.
Relationships of (A) head length, (B) snout depth, (C) orbit diameter, (D) anterior interorbital width, (E) posterior interorbital width, and (F) least interorbital width (as % of standard length) to standard length (mm) in Lepadichthys conwayi, new species.
Type specimens of Lepadichthys springeri. (A–D) USNM 359726, holotype, 24.8 mm SL, Sombrero Island, Batangas, Philippines; (E–G) USNM 359727, paratype, ca. 19 mm SL, Tagauayan Island, Palawan, Philippines. (A, G) Lateral views. (B, E) Dorsal views. (C, F) Ventral views. (D) Radiograph by S. Raredon.
Contributor Notes
Associate Editor: M. T. Craig.