Tandya Whitley, 1930

Smith-Vaniz, William F., 2004, Descriptions of Six New Species of Jawfishes (Opistognathidae: Opistognathus) from Australia, Records of the Australian Museum 56 (2), pp. 209-224 : 221-224

Status of Tandya Whitley

Whitley (1930) established the genus Tandya (type by original designation, Opistognathus maculatus Alleyne & Macleay, 1877 = O. papuensis Bleeker, 1868 ) for Australian jawfishes that have 12 dorsal-fin spines and upper jaws with a truncate maxilla extending posterior to a vertical from the posterior margin of the orbit. He contrasted his new genus only with Gnathypops Gill (type species Opistognathus maxillosus Poey, 1860 ), which was erroneously reported to have 8 (actually 11) dorsal-fin spines. Smith- Vaniz (1997) redescribed O. maxillosus , recognizing Gnathypops as a junior synonym of Opistognathus Cuvier. Inexplicably , both Whitley (1930) and McKay (1969) assigned Opistognathus darwiniensis Macleay, 1878 to Tandya although it has only 11 dorsal-fin spines. Three other jawfishes with 12 dorsal-fin spines that have sometimes been referred to Tandya are Opistognathus inornatus Ramsay & Ogilby, 1887 , Tandya latitabunda Whitley, 1937 and Tandya reticulata McKay, 1969 . Opistognathus inornatus differs from the allopatric O. papuensis only in colour pattern and its taxonomic rank is subjective.

Species in the following key that have 12 (rarely 13) dorsal-fin spines also have more precaudal vertebra than other opistognathids (12 or 13 versus 10 or 11), except O. darwiniensis with typically 12+19 vertebrae and 10 or 11 (usually 11) dorsal-fin spines. Opistognathus darwiniensis is also exceptional in having a second, irregularly developed, tubed lateral line (often with one or more branches on belly) present along the lower sides near the anal-fin origin. Numbers of dorsal-fin spines and precaudal vertebrae vary widely among percoids, and in the absence of a reasonably supported sister-group hypothesis for the Opistognathidae (see discussion in Gill & Mooi, 1993), polarity of such meristic characters is equivocal. High numbers of spines and precaudal vertebrae could have evolved in the ancestor of the Opistognathidae ; that possibility combined with the lack of character state concordance in O. darwiniensis , leads me to retain these species in a “catch-basket” Opistognathus , the oldest available generic name in the family, pending independent corroborative evidence of monophyly.

Key to Australian jawfishes

1 First 5–9 dorsal-fin spines transversely forked distally (posteriorly spines successively less deeply and more narrowly forked); skin covering spinous dorsal fin forming a broad dorsal hood to accommodate transversely forked spines; segmented anal-fin rays 10 or 11 .......................................................................................................................................... 2

Anterior dorsal-fin spines not transversely forked; skin covering spinous dorsal fin not forming a broad dorsal hood; segmented anal-fin rays 10–19 ........................................................................................................................ 3

2 Posterior edge of opercle and adjacent branchiostegal membranes dark and conspicuous; dorsal, anal, and caudal fins with two, broad dark stripes or bands ( Japan, Indonesia, Great Barrier Reef, and New Caledonia) .................................................................... Stalix histrio Jordan & Snyder, 1902

Posterior edge of opercle and adjacent branchiostegal membranes not conspicuously pigmented; dorsal, anal and caudal fins without dark stripes or bands (western Australia) ................................... Stalix flavida Smith-Vaniz, 1989

3 Dorsal-fin spines 10 or 11 .............................................................................................................. 4

Dorsal-fin spines 12 or 13 (rarely 13) ......................................................................................... 13

4 Body with 2 separate lateral lines, the ventral one irregularly developed along lower side in region of anal-fin origin, often with one or more branches on belly; head covered with close-set, tiny, brown spots and pelvic fins usually strongly barred; precaudal vertebrae 12 or 13 (northwestern Australia) ............. Opistognathus darwiniensis Macleay, 1878

Body with a single, dorsally positioned lateral line; colour pattern not as above; precaudal vertebrae 10 or 11 ................................................................................... 5

5 Segmented dorsal- and anal-fin rays 11–13 and 10–12, respectively ............................................... 6

Segmented do rsal- and anal-fin rays 14–20 and 13–19, respectively ............................................... 8

6 Opercle with a conspicuous dark blotch; scales on belly minute and distinctly embedded; body with about 80–99 oblique scales in longitudinal series; vomerine teeth 1–3; upper gill-rakers 14– 17 (eastern Australia) .......................................................... Opistognathus eximus ( Ogilby, 1908)

Opercle without a dark blotch; scales on belly, if present, small to moderate and not distinctly embedded; body with about 41–62

oblique scales in longitudinal series; vomerine teeth absent; upper gill-rakers 9–12 .............................................................................................................................. 7

7 Spinous dorsal without an ocellus; soft dorsal and anal fins mostly dark with a narrow pale basal stripe; no dark chin bar; outer premaxillary teeth relatively straight and with distinctly blunt tips; nape at least partially scaled (gulfs of Thailand and Carpentaria) .......................................................................................... Opistognathus macrolepis Peters, 1866

Spinous dorsal fin with a prominent ocellus; coloration of soft dorsal and anal fins not as above; dark chin bar present; outer premaxillary teeth variously curved and with pointed tips; nape usually naked (western Pacific, including Great Barrier Reef, Fiji and Samoa islands) ............................................................. Opistognathus sp. “chinstrap jawfish”

8 Floor of mouth between dentaries and “tongue” dark brown; dorsal fin X, 16–18, rarely 16; body with about 80–99 oblique scale rows in longitudinal series (eastern Australia) ......... Opistognathus jacksoniensis Macleay, 1881

Floor of mouth between dentaries and “tongue” pale; number of dorsal-fin spines and rays not in above combination; body with about 21–54 oblique scales in longitudinal series ......................................................................... 9

9 Posterior end of upper jaw produced as a thin flexible lamina in adults (beginning as a slight posteroventral projection in small juveniles); in at least adult males upper jaw extends to or beyond posterior margin of preopercle and appears somewhat scimitar- shaped; roof of mouth behind upper pharyngeal toothplates with a pair of slightly separated dark blotches; total dorsal-fin elements 25 (rarely 26); lateral-line terminus below verticals from 2nd to 4th segmented dorsal-fin rays (northern Australia) ..................... Opistognathus verecundus n.sp.

Posterior end of upper jaw rigid in adults, without a flexible lamina;

upper jaw not extending to posterior margin of preopercle, truncate or moderately rounded but never scimitar-shaped; roof of mouth behind upper pharyngeal toothplates immaculate; total dorsal-fin elements 25–30; lateral-line terminus below verticals from 4th to

17th segmented dorsal-fin rays .................................................................................................... 10

10 Segmented dorsal- and anal-fin rays 14–16 and 14 or 15, respectively; body naked anterior to a vertical between ultimate spine and 2nd segmented dorsal-fin rays; caudal vertebrae 18 (Great Barrier Reef) ...................................................................... Opistognathus seminudus n.sp. Segmented dorsal- and anal-fin rays 18–20 and 17–19,

respectively; body naked anterior to a vertical between 5th and

7th spines or 6th and 9th segmented dorsal-fin rays; caudal vertebrae 22 or 23 ........................................................................................................................ 11

11 Body naked anterior to a vertical line from 6th to 9th segmented dorsal-fin rays; lateral line terminus below verticals between 13th and 17th segmented dorsal-fin rays; body with 21–31 oblique scale rows (western Australia) ....................................................................... Opistognathus alleni n.sp.

Body naked anterior to a vertical from 5th to 7th dorsal-fin spines;

lateral line terminus below verticals between 4th and 8th segmented dorsal-fin rays; body with 38–51 oblique scale rows .................................................................. 12

12 Spinous dorsal fin with an oblong black spot (encircled by narrow white border) between spines 3–6 that extends slightly onto dorsum; dorsal-fin spines 11; vomerine teeth 2 or 3; sides of body uniformly pigmented (Elizabeth Reef) .................................... Opistognathus elizabethensis n.sp.

Spinous dorsal fin pigmentation not as above; dorsal-fin spines

10; vomerine teeth absent; sides of body with longitudinal row of

7 or 8 large pale spots and a few conspicuous small, black spots

(Great Barrier Reef and Coral Sea Plateau) ................................... Opistognathus stigmosus n.sp.

13 Dorsal fin with 4 or 5 large dark blotches that extend onto dorsum; lateral line terminus below verticals between 10th spine and 5th segmented dorsal-fin ray; 56–80 oblique scale rows in longitudinal series ............................................................................................................................................. 14

Dorsal fin pigmentation not as above; lateral line terminus below verticals between 6th and 13th segmented dorsal-fin ray; 78–129

oblique scale rows in longitudinal series ..................................................................................... 15

14 Dorsal fin with 4 dark blotches, first blotch extending onto distal half of fin; inner surface of mouth, and skin connecting dentary and maxilla pale; dorsum of head reticulated; total gill-rakers on first arch 26–29; vertebrae 12+19 (northern Australia) ..................... Opistognathus reticeps n.sp.

Dorsal fin with 5 dark blotches, first blotch only on base of fin;

much of inner surface of mouth, and skin connecting dentary and maxilla (hidden from view when mouth is closed) darkly pigmented; dorsum of head uniformly pigmented; total gill-rakers on first arch 23 or 24; vertebrae 13+19–21 (northern Australia and southern Papua New Guinea) ............................ Opistognathus latitabundus ( Whitley, 1937)

15 Body with pale reticulate network enclosing irregular tan blotches, each of which has one to several small, dark-brown spots; pectoralfin base (laterally and mesially) with a conspicuous dark spot about half diameter of eye; pelvic and anal fins white; vertebrae 13+18 (northwestern Australia) ............................................... Opistognathus reticulatus ( McKay, 1969)

Body with no to many dark spots on an otherwise uniformly pigmented body; pectoral-fin base not pigmented as above, either unmarked or typically with tiny black spots; pelvic and anal fins usually brownish, the anal fin with or without small spots; vertebrae

12+18–20 (usually 19) ................................................................................................................. 16

16 Body with numerous small spots, especially on dorsum of head; pectoral fin with several to many tiny dark spots; background coloration of body pale (in life, light tan), darker dorsally (Waigeo and Queensland to Darwin, Australia) ............................ Opistognathus papuensis Bleeker, 1868

Body usually without spots, if present, spots relatively large and sparse; pectoral fin typically unspotted; background coloration of body dark brown (Western Australia) ............. Opistognathus inornatus Ramsay & Ogilby, 1887

ACKNOWLEDGMENTS I thank the following for loans of specimens: G.R. Allen (WAM), W.N. Eschmeyer (CAS), A.C. Gill (BMNH), R.D. Mooi (MPM), J.C. Paxton (AMS), J.E. Randall (BPBM), H.K. Larson (NTM), and V.G. Springer and J.T. Williams (USNM). Colour photographs of jawfishes were generously provided by G.R. Allen, R.D. Mooi, and P.C. Heemstra, South African Institute of Aquatic Biology (formerly RUSI). I also thank R.D. Mooi for discussion of problems involving opistognathid intrafamilial relationships. The manuscript benefited from comments provided by Martin Gomon and an anonymous reviewer.