Classification / Names
Common names | Synonyms | Catalog of Fishes (gen., sp.) | ITIS | CoL | WoRMS | Cloffa
Actinopterygii (ray-finned fishes) > Cyprinodontiformes
(Rivulines, killifishes and live bearers) > Aplocheilidae
Etymology: Pachypanchax: Greek, pachys = fat + Panchax, a word created by Meinken in 1932 word created by Meinken in 1932; varatraza: Named for the Malagasy word varatraza, meaning east wind, in acknowledgement of the unanticipated presence of a Pachypanchax species in rivers draining the eastern slope of The Tsaratanana Massif (Ref. 57724).
Environment / Climate / Range
Freshwater; benthopelagic. Tropical
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 6.8 cm SL male/unsexed; (Ref. 57724)
Morphology | Morphometrics
soft rays: 17 - 19. Distinguished from Pachypanchax playfairii in lacking raised dorsolateral squamation and in details of its color pattern. Males without rows of discrete red dots on the flanks and red edging to the vertical fins; female lack any sort of black markings on the dorsal fin. Has the shortest pectoral fins (13.4% SL) among Malagasy Pachypanchax. Differs from Pachypanchax sakaramyi and Pachypanchax sparksorum by the absence of pectoral scales of reduced size. Can be distinguished from Pachypanchax omalonotus by the rounded dorsal and anal fins of males and their lack of discrete metallic gold spangling on the flanks; and also differs from the remaining Malagasy congeners by lack of iridescent white edging to, or darker submarginal banding on, the vertical fins (Ref. 57724).
Africa: Menambery, Fanambana and Ampanobe river basins in Madagascar (Ref. 57724).
Found in a wide range of habits: stream flowing under relatively intact forest cover at an altitude of 70 m above sea level consisting of a series of quiet pools with clay/sand bottoms, interspersed with short stretches of flowing water over sand/ gravel bottoms and with very turbid water; and stream flowing through modified low-altitude rain forest at an altitude of 30 m above sea level consisting of clay/sand bottom, interspersed with patches of bedrock with clear water and moderate current (Ref. 57724). Feeds on terrestrial and aquatic insects (Ref. 57724).
Loiselle, P.V., 2006. A review of the Malagasy Pachypanchax (Teleostei: Cyprinodontiformes, Aplocheilidae), with descriptions of four new species. Zootaxa 1366:1-44. (Ref. 57724)
IUCN Red List Status (Ref. 90363)
CITES (Ref. 94142)
Threat to humans
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass conversion
CollaboratorsPicturesStamps, CoinsSoundsCiguateraSpeedSwim. typeGill areaOtolithsBrainsVision
Estimates of some properties based on models
Phylogenetic diversity index (Ref. 82805
= 0.5079 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01000 (0.00244 - 0.04107), b=3.04 (2.81 - 3.27), based on all LWR estimates for this body shape (Ref. 93245
Trophic Level (Ref. 69278
): 3.6 ±0.5 se; Based on size and trophs of closest relatives
Resilience (Ref. 69278
): High, minimum population doubling time less than 15 months ().
Vulnerability (Ref. 59153
): Low vulnerability (10 of 100) .