Gnatholepis yoshinoi Suzuki and Randall, 2009

Larson, Helen K. & Buckle, Duncan J., 2012, A revision of the goby genus Gnatholepis Bleeker (Teleostei, Gobiidae, Gobionellinae), with description of a new species, Zootaxa 3529 (1), pp. 1-69 : 55-57

Gnatholepis yoshinoi Suzuki and Randall, 2009

( Figs 27–29)

Gobius anjerensis — Kuiter and Tonozuka 2001: 671, figs A, B, D–F (Bali, Indonesia; Mabul, Malaysia).— Hayashi and Shiratori 2003: 96, fig. 175 ( Japan).

Gnatholepis yoshinoi Suzuki and Randall, 2009: 84–87 (Oura Bay, Okinawa, Ryukyu Islands, Japan).

Diagnosis. (From Suzuki and Randall 2009). A small Gnatholepis (up to 31 mm SL) with cycloid scales on head, predorsal and pectoral fin base, distinct flap present at end of lower lip; first dorsal fin tall, pointed, with third spine longest; distinctive black blotch on membrane behind first spine of first dorsal fin and one or more smaller black spots on membrane between second and third spines; pectoral fin with rows of fine dark spots and speckles; second dorsal and anal fin rays nearly always I,11; pectoral rays 15; lateral scales 27; about 7 cycloid predorsal scales.

Figure 1 of the holotype and other photographs in Suzuki and Randall (2009: Figs 1–3 ) show the pelvic fins having three bands of light and dark pigment (unlike the pattern on the pelvic fins of any other Gnatholepis species ), but the description does not mention this. This pattern of whitish and dark grey to blackish cross-bands on the pelvic fins is shown on several photos of this species in the wild sent to us by Rudie Kuiter, and appears to be a distinctive feature of this species ( Figs 27–29).

Gnatholepis yoshinoi resembles G. anjerensis but the black blotches on the anterior part of the first dorsal fin and row of large dark blotches along the lower side of the body and side of head are characteristic, as are the dark and light cross-bands on the pelvic fins. The three known specimens show some differences in first dorsal fin shape, with the fin varying from tall and rounded to very tall and pointed, as can be seen in published photographs ( Kuiter & Tonozuka 2001: 671, figs A, B, D–F; Suzuki & Randall 2009: figs 1–3) and in the holotype ( Fig. 28 ). A photograph of this species in Sydney Harbour, New South Wales, by Rudie Kuiter, shows a rounded fin and colour pattern resembling that in Kuiter and Tonozuka (2001: 671, fig. E). We are not sure why Suzuki and Randall (2009) did not refer to the other photographs of this species in Kuiter and Tonozuka (2001).

The fish in Figure 29 is unusual in that the first dorsal fin lacks the black blotches (and thus more resembles G. anjerensis ) but the pelvic fin can be seen as banded, which is not exhibited in G. anjerensis .

We consider that Hayashi and Shiratori’s (2003: 96) Figure 175 is of this species, although the tip of the first dorsal fin is missing (looks like a piece has been taken out of it). However, the characteristic dark and light banding on the pelvic fins is visible (through the transparent pectoral fin membrane), as is the smudgy dark cheek mark that tends to cover the vertical black bar (and its other colour pattern features).

Figures

FIGURE 1. Sensory pores and papillae in Gnatholepis anjerensis, SAIAB 2112, Mauritius, 46 mm SL male. Scales omitted.

FIGURE 28. Holotype of Gnatholepis yoshinoi, NSMT P.91420. Photograph by Toshiyuki Suzuki.

FIGURE 29. Probable Gnatholepis yoshinoi, Bali, Indonesia. Photo by Rudie Kuiter. Note banded pelvic fins, but no black blotch on dorsal fin.