Siphamia cuneiceps Whitley

Gon, Ofer & Allen, Gerald R., 2012, 3294, Zootaxa 3294, pp. 1-84 : 31-32

Siphamia cuneiceps Whitley

Figure 15

Siphamia cuneiceps Whitley, 1941: 29 , fig. 20 (type locality, Fraser Island , Queensland, Australia; holotype, AMS IB.1016).

Diagnosis: Dorsal rays VI+I,8; anal rays II,8; pectoral rays 11–13, unbranched and compressed distally; tubed lateral-line and median predorsal scales unknown (most scales missing on all specimens); total gill rakers 2–4 + 9–11 = 11–14; developed gill rakers 0 + 6–9; gill rakers on ceratobranchial 6–7. Body relatively slender, its depth 3.7–4.1 in SL, and body width 1.6–2.0 in the depth; eye diameter 3.7–4.2 in head length; first dorsal spine 1.2–1.3 in second spine; second dorsal spine 2.8–2.9, spine of second dorsal fin 5.0–5.5, and second anal spine 5.1–6.7, all in head length; pectoral-fin length 5.4–6.1 and pelvic-fin length 5.2–6.4 in SL; caudal-peduncle length 1.1–1.5 in distance between pelvic spine insertion and anal-fin origin. Preopercular edge and ridge smooth, the ventral edge weakly ossified and usually slightly crenulate. Palatines with 2–3 series of small teeth. Scales ctenoid, large, thin and deciduous (see Remarks below); tubed lateral-line scales with vertical series of papillae. Tip of light organ on each side of tongue bound by membrane.

Colour in life: unknown.

Colour in alcohol: variable, depending on the proportion of expanded melanophores; body brown to dark brown, peppered with darker dots; area below dorsal-fin base and dorsal part of caudal peduncle frequently with fewer dots and generally paler; snout paler than body; 1–2 lines of small faint dark dots from below anterior nostril to below rear edge of eye; a wider diffuse dark stripe from rear edge of eye to above pectoral-fin base; edge of preopercular ridge and branchiostegal rays behind maxilla with small dark brown dots; second dorsal, anal, and pelvic fins with small dark dots on membrane between anterior most rays; dark pigment dots reach higher up these fins anteriorly; similar dots present proximally on middle caudal-fin rays; palate with larger dark brown dots; peritoneum with large, conspicuous dark brown dots; stomach with similar, but fewer dots; intestine with smaller and denser dark dots.

Smallest specimens examined, WAM P.30080-010, 20.6 mm, from Shark Bay, Western Australia and largest specimen, ANSP 122184, 39.0 mm, from Moreton Bay, Queensland.

Remarks: See Tables 1–3 for frequency distributions of pectoral-fin rays, lateral-line scales and gill rakers. The majority of the specimens were missing all scales. One specimen had several lateral-line scales on the posterior part of the body the last of which were at the position of the 16 th or 17 th scale. The last two lateral-line scales are also present and are pitted. Judging from the imprint left by the missing scales on the caudal peduncle this species appears to have about 19–20 tubed lateral-line scales followed by 4–5 perforated or pitted ones. Body scales are cycloid to weakly ctenoid. Ctenii appear on the middle posterior margin of the scales of the lower part of the body behind the tip of the pectoral fin and gradually increase in more posterior scales. In a number of specimens (e.g. the holotype and AMS I.20923-004) the first infraorbital pore is a complex of three small pores. A similar modification of this pore was also found in one specimen of S. cephalotes (CSIRO B3505) and was also observed occasionally in other apogonid species (O. Gon, unpublished data). Dark dots were more concentrated along the middle of the body in several specimens, indicating the presence of a mid-lateral stripe possibly originating behind the eye.

Siphamia cuneiceps is the only member of the S. tubulata species group and in the genus that lacks developed gill rakers on the upper limb of the first gill arch. Its slender body clearly separates it from all other congeners (body depth 2.3–3.3 in SL), except S. cephalotes . Although S. cephalotes has a similar colour pattern it is easily distinguished in having 15–18 developed gill rakers. In addition, the snout of S. cuneiceps is pointed with the lower jaw clearly jutting out in front of upper jaw compared to S. cephalotes , which has a more rounded snout and equal jaws. See Remarks for S. cephalotes for additional differences between the two species. Small, preserved specimens of S. roseigaster may also be confused with preserved S. cuneiceps , but the former species has 9–11 (usually 10) second dorsal- and anal-fin rays and more gill rakers ( Table 3).

This species is found in Western Australia, from Shark Bay to the vicinity of Mandurah , and along the east coast of Queensland, from Cape York to Moreton Bay ( Fig. 7). It is usually collected by trawl. The holotype was taken at 15 fathoms ( Whitley 1941) and in Shark Bay specimens were collected at a depth of 1–4 m. A 28.4 mm mouthbrooding male had about 30 eggs, 0.8 mm in diameter, in its mouth .

Material examined: WESTERN AUSTRALIA: Shark Bay , AMS IB.3044, 25.8 mm; CSIRO A907 , 34.0 mm ; CSIRO A908 31.1 mm ; WAM P.28312-003, 28.3 mm; WAM P.30080-010, 2: 20.6–24.8 mm; WAM P.30084-004, 2: 22.0– 27.2 mm; WAM P.30165-007, 3: 26.6–28.6 mm. Abrolhos , WAM P.29884-002, 2: 30.0– 30.9 mm. Lancelin, Carnac Island , WAM P.5903, 4: 28.2–31.2 mm. Perth , WAM P.5904, 32.6 mm. Murray Bight , WAM P.29314-001, 32.6 mm. QUEENSLAND: Cape York , AMS I.20923-004, 34.9 mm. Fraser Island , AMS IB.1016, 37.7 mm (holotype) ; AMS I.43753-001, 2: 34.5–38.1 mm (paratypes). Moreton Bay , ANSP 122184 , 39.0 mm ; WAM P.28824-004, 28.4 mm.