Synchiropus valdiviae (Trunov, 1981)

M. E. Anderson, D. L. Stein & H. W. Detrich, 2005, Additions to the ichthyofauna of the Tristan da Cunha Group, South Atlantic Ocean., Zootaxa 1072, pp. 27-33 : 28-30

Synchiropus valdiviae (Trunov, 1981)

(Fig. 1)

Presently there are two classifications of dragonets, variously at odds with one another (Fricke 1982, 2002; Nakabo 1982, 1983). Although Nakabo (op. cit.) and Nakabo and Hartel (1999) placed this species in Foetorepus Whitley , we follow Fricke (2002) in placing it in Synchiropus Gill .

Two adult females and three juveniles of S. valdiviae were taken in the beam trawl at station 85 just north of Nightingale Island. Originally described from a single adult male from Walvis Ridge, a second male has been discovered, and both are from the same locality (Trunov, 1981; Fricke, 1985, but not a paratype as stated). Our specimens are identified on the basis of their agreement with the two males in several characters which separate the species from other Atlantic congeners (reviewed by Nakabo and Hartel, 1999): their coloration, bowed lateral line, counts and proportions, which separate the species from other Atlantic congeners.

Counts and measurements (ranges of the two adult females first, followed in parentheses by juveniles): Vertebrae 7 + 13-14 (7 + 14); D I V, 8 (IV, 8 9); A 7 (7); P 22 (21-22); pelv. I, 5 (I, 5); C ii -iii + 10 + ii (ii -iii + 10 + i -ii); gill rakers 0 + 7 (0 + 7-8); branchiostegal rays 6 (6); pseudobranch filaments 12 (6-7). Following proportions as percent SL: body width 16.8-18.3 (16.1-16.7); body depth 15.3-15.8 (14.9-15.0); caudal peduncle depth 5.9-6.5 (5.7-5.9); predorsal length 30.8-32.1 (30.7-32.1); preanal length 53.9-54.4 (52.4-52.6); caudal fin length 28.6- 30.9 (30.0- 31.2); head length 27.5-27.8 (29.6-30.4); head depth 15.1-17.1 (15.1-16.7); eye diameter 11.3-11.9 (13.1-13.3); snout length 6.5-7.4 (6.3-6.7); upper jaw length 9.7-10.1 (10.2-10.4); interorbital width 2.4-2.5 (1.5-2.2); 1st dorsal spine length 15.4-15.6 (15.3-15.4); 2nd dorsal spine length 11.1-11.9 (12.2); 3rd dorsal spine length 10.0- 0.1 (8.9); 4th dorsal spine length 6.8- 7.0 (7.0-7.1); 1st dorsal ray length 18.1-19.0 (20.5-23.2); last dorsal ray length 18.6- 19.8 (17.8-18.0); 1st anal ray length 9.2-9.4 (10.8-12.0); last anal ray length 19.3-20.0 (20.1- 23.0); 1st to 2nd dorsal distance 6.0-6.2 (6.5-7.0); 1st dorsal base 7.1-7.3 (6.5-6.7); 2nd dorsal base 30.3- 30.5 (28.4-31.3); anal base 23.2-24.0 (20.0-21.6); pectoral base depth 8.6-9.1 (7.8-8.2); pectoral fin length 21.2-21.9 (15.8-19.0); pelvic fin length 27.4-27.9 (29.2-30.7).

First dorsal spine not elongate, only very slightly so in juvenile male. Lateral line distinctly bowed on body, sharply descending to midline between third and fifth dorsal rays (Trunov, 1981, shows bow extending to last ray). Anal fin origin on vertical through fourth dorsal ray, not first as stated by Trunov, but illustrated by him under third. Preopercular spine with trifid tip in all. Body reddish with yellow variegations, first dorsal fin membrane dusky except in juvenile male which has a solid black membrane except proximally. Membrane of anal fin with yellowish distal streak. Membrane of second dorsal fin with indistinct yellowish areas.

Material: SAIAB 74966 (2 females, 52.7-54.5 mm SL; male, 61.6 mm SL); sta. 85/BT 44; 37° 20.3'S, 12° 30.0'W; 2 m beam trawl; 188-201 m; 12:59-13:11 hrs; 7 July 2004. SAIAB 74969 (2 females, 106.5-116.8 mm SL); sta. 85/BT 45; 37° 19.2'S, 12° 29.9'W; 2 m beam trawl; 210- 223 m; 15:29-15:50 hrs; 7 July 2004.