Life-history characteristics of eleotrid fishes of the western hemisphere, and perils of life in a vanishing environment

Abstract

The term amphidromous was coined (Myers in Copeia 1949:89-97, 1949b to describe diadromous life histories that include migrations, not associated with reproduction, that are between fresh and marine waters. This concept has facilitated evaluations of life cycles among a number of groups of fishes including some belonging to the family Eleotridae. Information was gathered on life history patterns of eleotrid fish species that have been recorded from both fresh and brackish or marine waters of the east and west coasts of North, Middle, and South America, including adjacent islands, seeking evidence of diadromy and especially of amphidromy. Convincing evidence was found of diadromy in the life cycles of four species from the east coast (with another two species possibly in this category), and of three species from the west coast of the Americas and adjacent islands. However, there was convincing evidence of amphidromy in only one species from the east coast and adjacent islands, with another three species or species populations possibly in this category, and in three species from the west coast and adjacent islands. It seems possible from the available information that there may be variation among populations in life cycles of some of these species. However, it remains for the use of modern techniques to allow more definitive determinations of life history patterns of these eleotrid species populations. Serious concern exists with respect to the conservation of all diadromous species because of the worldwide emphasis on river manipulations, especially of dam construction. Resident diadromous organisms are being impeded in their migrations, and thus imperiled in their potential for survival, depending on the nature of river alterations and the abilities of the organisms to cope with them.

Exploring the molecular diversity of Eleotridae (Gobiiformes) using mitochondrial DNA

“…Dormitator maculatus and Gobiomorus dormitor , which are found in rivers and estuaries of Florida, the Gulf of Mexico and the Caribbean, as well as in Brazil (Castro‐Aguirre, ; Froese & Pauly, ; Gilbert & Williams, ; Robins & Ray, ), are species adapted to major fluctuations in salinity, but have low dispersal capacity (Nordlie, ). While specimens from northern South America were not included in the present study, the analyses indicated the presence of two substantial evolutionary lineages of G. dormitor in the disjunct populations found in Veracruz (Mexico) and the Caribbean (Figure ).…”

“…used to separate lineages (Hebert et al, 2003). The pairwise genetic distance matrix ( Robins & Ray, 1986), are species adapted to major fluctuations in salinity, but have low dispersal capacity (Nordlie, 2012).…”

“…The very biodiverse Neotropical region exhibits a high level of endemism (Moritz, Patton, Schneider, & Smith, 2000;Morrone, 2014) including fish taxa (Levêque, Oberdorff, Paugy, Stiassny, & Tedesco, 2008) that includes members of the family Eleotridae. There are 26 recognized species of this family in the region that can serve as models for the evaluation of diversity levels of this group, since they are restricted to rivers and estuaries and show a low dispersal capacity (Nordlie, 2012).…”

“…Assuming that intraspecific diversity is much lower than interspecific variation (Hebert et al, 2003;Ward, Hanner, & Hebert, 2009), the use of DNA barcoding in Neotropical fishes has provided important insights into the diversity of this fauna, in particular the identification of cryptic species, evidence of the existence of new species and important contributions to the resolution of taxa that are difficult to distinguish using a traditional morphological approach (Amaral, Brito, Silva, & Carvalho, 2013;Hebert, Penton, Burns, Janzen, & Hallwachs, 2004;Tornabene, Baldwin, Weigt, & Pezold, 2010;Ward, Zemlak, Innes, Last, & Hebert, 2005). Interesting examples are species of the genus Eleotris from the western Atlantic Ocean, which contain a number of cryptic species having confounding morphological characteristics that frequently lead to errors in taxonomic identification (Guimarães-Costa et al, 2016;Nordlie, 2012;Pezold & Cage, 2002).…”

Predicting ecological and phenotypic differentiation in the wild: a case of piscivorous fish in a fishless environment

“…The bigmouth sleeper [ Gobiomorus dormitor (Lacepède, 1800)] is an eleotrid fish inhabiting tropical and subtropical coastal freshwater and brackish environments in the Caribbean, south‐eastern Florida, southern Texas, and the Atlantic slope of Central and northern South America (Lindquist, ; Gilmore, ). Gobiomorus dormitor is commonly catadromous or amphidromous (Darnell, ; Winemiller & Ponwith, ; Adelsberger, ; Nordlie, ), using saltwater regions during egg laying or larval development, but is also known to reproduce in some landlocked lakes and reservoirs (Darnell, ; McKaye, Weiland & Lim, ; Holmquist, Schmidt‐Gengenbach & Yoshioka, ; Bedarf et al ., ; Bacheler, Neal & Noble, ). In coastal streams and lakes (its ancestral environment), G. dormitor is a benthic, ambush predator, feeding primarily on fish and large invertebrates (McKaye, Weiland & Lim, ; Winemiller & Ponwith, ; Bedarf et al ., ; Bacheler, Neal & Noble, ).…”