Tympanopleura

Walsh, Stephen J., Ribeiro, Frank Raynner Vasconcelos & Py-Daniel, Lúcia Helena Rapp, 2015, Revision of Tympanopleura Eigenmann (Siluriformes: Auchenipteridae) with description of two new species, Neotropical Ichthyology (Neotrop. Ichthyol.) 13 (1), pp. 1-46 : 42-43

Key to the species of Tympanopleura

1. Body typically with prominent, irregular spots scattered over top of head, dorsum, sides, and fins, or with a large dark blotch of melanophores on flanks above anal-fin base, streaks in each caudal-fin lobe, and dark pigment on chin (pigmentation occasionally light or faded in preserved specimens) .................................................... 2

1’. Body with relatively uniform pigmentation, consisting of light to moderate stippling, darkest on top of head, dorsum, and sides, lacking well-defined spots or large blotches.......................................................................... 3

2. Pectoral-fin rays 7-9; anal-fin rays 23-30, usually 25- 29; total gill rakers on anterolateral margin of first arch usually 14-18, rarely greater (to 23); pigmentation variable, but usually consisting of: broad, dark, crescent shaped patch on chin ( Fig. 1a ); black upper lip; large blotch formed from diffuse melanophores on sides above anal fin; dark basal patch or longitudinal stripe in each caudal-fin lobe; pectoral, pelvic, and caudal fins often with dark marginal band........................................ ................................. Tympanopleura atronasus ( Fig. 9 ).

2’. Pectoral-fin rays 10-13; anal-fin rays 28-37; total gill rakers on anterolateral margin of first arch 24-33; pigmentation usually consisting of large irregular spots extensively distributed on head, dorsum, sides of body, and fins ...................... Tympanopleura rondoni ( Fig. 18 ).

3. Anal-fin rays 31-42....................................................... 4.

3’. Anal-fin rays 23-30... Tympanopleura cryptica ( Fig. 13 ).

4. Maximum body size <50 mm SL; mouth weakly inferior; pseudotympanum typically ovoid, often bulging slightly outward and semi-translucent; gas bladder without posterior terminal diverticula; usually with prominent transverse bar of dark melanophores at base of caudal fin (pigmentation occasionally light or faded in preserved specimens)................ Tympanopleura piperata ( Fig. 16 ).

4’. Maximum body size> 50 mm SL; mouth distinctly inferior; pseudotympanum typically triangular, opaque; gas bladder with pair of posterior terminal diverticula; occasional scattered pigmentation at base of caudal fin, but not forming distinctive hourglass-shaped transverse bar................................................................................. 5.

5. Pectoral-fin spine long, robust, about 19-24% SL, often reaching to or past pelvic-fin origin; anal-fin base short, about 26-34% SL; anal-fin rays 31-36, usually 35 or fewer; postcleithral process typically well developed, short, rigid, triangular or lanceolate in shape; maximum body size> 80 mm SL ................................................... ................................... Tympanopleura brevis ( Fig. 11 ).

5’. Pectoral-fin spine shorter, about 16-18% SL, not reaching past pelvic-fin origin; anal-fin base longer, about 34-40% SL; anal-fin rays 32-42, usually 35 or more; postcleithral process absent, or, if present, minute and feebly developed; maximum body size <80 mm SL ................ Tympanopleura longipinna ( Fig. 14 ).

Figures

Fig. 1. Dorsal and ventral head profiles of species of Tympanopleura: (a) T. atronasus, INHS 106400 (82.4 mm SL); (b) T. brevis, ANSP 194010 (63.3 mm SL); (c) T. cryptica, INHS 40163 (84.9 mm SL); (d) T. longipinna, MZUSP 114000 (73.0 mm SL, holotype); (e) T. piperata, ANSP 194022 (45.6 mm SL); (f) T. rondoni, ANSP 194015 (75.3 mm SL). Scale bars: a-d, f = 1 cm; e = 5 mm.

Fig. 9. Tympanopleura atronasus. (a) INHS 106400 (96.4 mm SL), female, Rio Nanay, Loreto Region, Peru; (b) UF 185769 (89.4 mm SL, male), rio Amazonas, Amazonas State, Brazil.

Fig. 18. Tympanopleura rondoni. UF 185776 (124.0 mm SL), nuptial male, río Mamoré, Beni Department, Bolivia.

Fig. 13. Tympanopleura cryptica, new species. (a) holotype, MUSM 47102 (84.9 mm SL), pre-nuptial male, río Orosa, Loreto Region, Peru; (b) paratype, INPA 35926 (65.3 mm SL), nuptial male, rio Purus, Amazonas State, Brazil.

Fig. 16. Tympanopleura piperata. (a) ANSP 194022 (47.5 mm SL), female, rio Negro, Amazonas State, Brazil; (b) holotype, FMNH 53243 (ex. CM 1708; 47.3 mm SL), male, Essequibo River, Cuyuni-Mazaruni Region, Guyana, reproduced from Eigenmann (1912; originally cited as 64 mm TL).

Fig. 11. Tympanopleura brevis, ANSP 194010 (68.5 mm SL), prenuptial male, rio Jutai, Amazonas State, Brazil.

Fig. 14. Tympanopleura longipinna, new species. Holotype, MZUSP 114000 (73.0 mm SL), female, rio Madeira, Rondônia State, Brazil.