A New Genus and Species of Clingfish (Teleostei: Gobiesocidae) from Western Australia
Nettorhamphos radula, new genus and species, is described from two specimens, 20.3–40.2 mm SL, trawled from sponge and algae reefs between 30–40 meters in depth offshore from Fremantle, Western Australia. The new taxon is distinguished from all other members of the Gobiesocidae by having vast fields of tiny conical teeth throughout the oral jaws that are arranged in multiple, regular rows along the lingual surface of the premaxilla and the dentary. The new taxon is tentatively considered a close relative of two other southern Australian endemic clingfish taxa (Posidonichthys and the undescribed “Genus A”) based on the presence of a well-developed and heavily ossified subopercular bone that articulates strongly with both the opercle (dorsally) and the preopercle (anteriorly).
Nettorhamphos radula, WAM P.26052-004, holotype, 40.2 mm SL, Indian Ocean, Western Australia.
Nettorhamphos radula, WAM P.25805-004, paratype, 20.3 mm SL, Indian Ocean, Western Australia.
Nettorhamphos radula, WAM P.25805-004, paratype, 20.3 mm SL. Line drawing of head in dorsal, lateral, and ventral view showing position of cephalic lateral line canal pores. Abbreviations: AN, anterior nostril; FL, fleshy lobe; LC, lacrimal canal pores; MC, mandibular canal pores; NC, nasal canal pores; PN, posterior nostril; PO, postorbital canal pores; PR, preopercular canal pores.
Computed tomography scanned anterior skeleton, including cranium, paired-fin girdles, and abdominal region of vertebral column, of Nettorhamphos radula, WAM P.25805-004, paratype, 20.3 mm SL. (A) Dorsal view. (B) Lateral view. (C) Ventral view. Single scale bar shared by A–C. Abbreviations: ACh, anterior ceratohyal; Ana, anguloarticular; Apa, autopalatine; Asph, autosphenotic; Bh, basihyal; Boc, basioccipital; Bp, basipterygium; Br, branchiostegal rays; Cb5, ceratobranchial five; Cl, cleithrum; De, dentary; DPcl, dorsal postcleithrum; E, ethmoid; Ec, epicentral; Epoc, epioccipital; Fr, frontal; Hy, hyomandibular; Ihc, interhyal; Iop, interopercle; La, lacrimal; LE, lateral ethmoid; Mx, maxilla; Na, nasal; NS, neural spine; Op, opercle; Pa, parietal; PCh, posterior ceratohyal; Pmx, premaxilla; Pop, preopercle; Pro, prootic; Psph, parasphenoid; Pt, posttemporal; Pte, pterotic; Q, quadrate; R, fin ray; Ra, retroarticular; Ri, rib; Scl, supracleithrum; Soc, supraoccipital; Sop, subopercle; Sy, symplectic; Ur, urohyal; V, vertebral centrum; VPcl, ventral postcleithrum.
Computed tomography scanned jaws, hyopalatine arch, and opercular series of Nettorhamphos radula, WAM P.25805-004, paratype, 20.3 mm SL. (A) Lateral view. (B) Medial view. (C) Anterolateral view. (D) Ventral view of isolated premaxillae. (E) Dorsal (upper) and ventral (lower) views of isolated dentaries. Scale bar shared between A and B. Abbreviations: Ana, anguloarticular; Apa, autopalatine; De, dentary; Ecpt, ectopterygoid; Hy, hyomandibular; Iop, interopercle; La, lacrimal; Mx, maxilla; Op, opercle; Pmx, premaxilla; Pop, preopercle; Q, quadrate; Ra, retroarticular; Sop, subopercle; Sy, symplectic.
Computed tomography scanned hyoid bar (A, B) and pharyngeal jaws (C–E) of Nettorhamphos radula, WAM P.25805-004, paratype, 20.3 mm SL. (A) Lateroventral view. (B) Medial view. (C) Dorsal view. (D) Ventral view. (E) Anterior view. Single scale bar shared between A and B and C–E. Abbreviations: ACh, anterior ceratohyal; Bh, basihyal; Br, branchiostegal rays; Cb5, ceratobranchial 5; DHh, dorsal hypohal; Ih, interhyal; Pb3TP, pharyngobranchial 3 toothplate; PCh, posterior ceratohyal; Uh, urohyal.
Computed tomography scanned skeleton of Nettorhamphos radula, WAM P.25805-004, paratype, 20.3 mm SL. (A) Dorsal view. (B) Lateral view. (C) Ventral view. (D) Close up of box in B showing posterior region of vertebral column, dorsal, anal, and caudal fin skeletons. Single scale bar shared between A–C. Scale bar not provided for D. Abbreviations: Ep, epural; HS1, hemal spine on vertebral centrum 17; LHP, lower hypural plate; NS1, neural spine of the first vertebral centrum; PU2, second preural centrum; R, fin ray; UC, ural centrum; UHP, upper hypural plate; V17, vertebral centrum 17.
Adhesive disc of Nettorhamphos radula, WAM P.26052-004, holotype, 40.2 mm SL. (A) Adhesive disc stained with cyanine blue, in ventral view. (B) Schematic illustration of adhesive disc with intact papillae in disc regions A–D shown in gray. Anterior margin of disc covered by gill membrane along midline. ‘Scars' of dislodged papillae visible on the surface of the disc in A not indicated in B.
Computed tomography scanned paired-fin girdles of Nettorhamphos radula, WAM P.25805-004, paratype, 20.3 mm SL. (A) Dorsal view. (B) Ventral view. (C) Lateral view. (D) Anterior view. Single scale bar shared between A–D. Abbreviations: Bp, basipterygium; Cl, cleithrum; Cor, coracoid; DPcl, dorsal postcleithrum; PR, pectoral radial; Pt, posttemporal; R, fin ray; Sc, scapula; Scl, supracleithrum; SR, spinous pelvic-fin ray; VPcl, ventral postcleithrum.
Skin surface of Nettorhamphos radula, WAM P.26052-004, holotype, 40.2 mm SL. (A) Overview of dorsal surface of head, right side, anterior to top of page. (B) Close up of box in A. (C) Close up of box in B. (D) Skin surface after cyanine blue staining.
Distribution of sampling localities for Nettorhamphos radula along the coast of Western Australia. Gray square indicates type locality. Prepared by M. Allen.
Computed tomography scanned anterior skeleton of southern Australian clingfishes with subopercular spines. (A) “Genus A Species 1,” NMV A 20781, 24.7 mm SL. (B) Posidonichthys hutchinsi, TCWC 17260.03, 15.0 mm SL. (C) Creocele cardinalis, NMV A 20789-002, 50.1 mm SL. Subopercle of left side highlighted in green.
Contributor Notes
Associate Editor: W. L. Smith.