Chelorchestia Bousfield, 1984

Serejo, Cristiana S., 2009, Talitridae *, Zootaxa 2260 (1), pp. 892-903 : 893

Chelorchestia Bousfield, 1984

Diagnosis. See Bousfield (1984).

Remarks. With the transfer of T. limicola to Chelorchestia , this is the first record of this genus for the Western Pacific region. The five previously known species of Chelorchestia were confined to the Americas: C. darwinii ( Müller, 1864) and C. forceps Smith & Heard, 2001 found on the Atlantic side and C. colombiensis Valencia & Giraldo, 2009 , C. costaricana ( Stebbing, 1906b) and C. vaggala ( Bowman, 1977) on the Eastern Pacific side. Bousfield (1984) also suggested the occurrence of Chelorchestia from the Eastern Atlantic – Nigeria, although this material has never been described.

Essentially Chelorchestia seems to have a Gondwanan distribution and with a consequently old origin, about 100 Ma. Despite the very scarce fossil record of the amphipods, Bousfield (1984) postulated a hypothesis for the evolution of the talitrids, which apparently evolved from a 5-dentate hyalid ancestor by the middle Cretaceous (110-90 Ma). The palustral group, including Chelorchestia and four other genera, would be one of the first to evolve as they are very water dependent. By the late Cretaceous (90-70 Ma) the diversification of the flowering plants and rhizophoroid mangrove swamps developed through the coastal tropics and provided suitable habitats for the explosion and colonization of the talitrids – initially in the mangroves and coastlines of the world and latter on invading the litter of the forest by the early Cenozoic time (60 Ma).