Simpsonichthys (Spectrolebias)

Wilson J. E. M. Costa, 2007, Taxonomic revision of the seasonal South American killifish genus Simpsonichthys (Teleostei: Cyprinodontiformes: Aplocheiloidei: Rivulidae)., Zootaxa 1669, pp. 1-134: 42

publication ID

z01669p001

publication LSID

lsid:zoobank.org:pub:F23FABE8-719E-4F7E-B225-A9C5D45CCFCE

persistent identifier

http://treatment.plazi.org/id/7FEDE207-4D0C-4E11-2985-703BCEE97733

treatment provided by

Thomas

scientific name

Simpsonichthys (Spectrolebias)
status

 

Subgenus Spectrolebias  Costa & Nielsen, 1997

Spectrolebias  ZBK  Costa & Nielsen, 1997: 258 (type species Spectrolebias semiocellatus  ZBK  Costa & Nielsen, by original designation; first proposed as a genus).

Diagnosis

Distinguished from all other cynolebiatins by two unambiguous synapomorphies (Costa, 2006a): a long (vs. short) hyomandibula and a narrowed (vs. wide) proximal tip of the fourth ceratobranchial.

Included species

Simpsonichthys chacoensis  (Amato), S. semiocellatus  ZBK  (Costa & Nielsen), S. filamentosus  ZBK  Costa, Barrera & Sarmiento, S. costai  (Lazara), and S. reticulatus  ZBK  Costa & Nielsen.

Distribution

Southern Amazonian river drainages, including rio Madeira, Xingu, Araguaia and Tocantins, and Paraguayan Chaco, río Paraguay basin (Figs. 1 and 4).

Key to species of the subgenus Spectrolebias 

1a. Dorsal fin rounded in males; dark suborbital and postorbital bars........................................................2

1b. Dorsal fin pointed in males; no bars on head........................................................................................3

2a(1a). Dorsal-fin rays 23-25 in males, 13-15 in females; flank greenish blue with dark red crimson scale margins in males................................................................................................................. S. reticulatus  ZBK 

2b(1a). Dorsal-fin rays 21-23 in males, 16-19 in females; flank dark brown to black with light blue dots in males.......................................................................................................................................... S. costai 

3a(1b). Anal-fin rays 23-25 in males; flanks light orange to translucent, unpaired fins pale red in males........................................4

3b(1b). Anal-fin rays 26-28 in males; flanks and unpaired fins dark bluish gray in males............................... S. chacoensis 

4a(3a). Frontal squamation E-patterned; anal fin pointed and with long filaments in males; no black spot on anal fin in males.............................................................................................................. S. filamentosus  ZBK 

4b(3a). Frontal squamation F-patterned; anal fin rounded and without filaments in males; black and blue spot on posterior portion of distal edge of anal fin in males................................................. S. semiocellatus  ZBK