Habitat associated morphological divergence in two Neotropical fish species

  • Langerhans R
  • Layman C
  • Langerhans A
 et al. 
  • 3


    Mendeley users who have this article in their library.
  • N/A


    Citations of this article.


We examined intraspecific morphological diversification between river channel and lagoon habitats for two Neotropical fish (Bryconops caudomaculatus, Characidae; Biotodoma wavrini, Cichlidae). We hypothesized that differences between habitats (e.g. flow regime, foraging opportunities) might create selective pressures resulting in morphological divergence between conspecific populations. We collected fish from four channel-lagoon habitat pairs in the Río Cinaruco, Venezuela, and compared body morphology using geometric morphometrics. There were two aspects of divergence in both species: (1) placement of maximum body depth and (2) orientation of the mouth. For both species, maximum body depth was positioned more anteriorly (i.e. fusiform) in the river channel than in lagoons. Both species exhibited a relatively terminal mouth in lagoons compared to the channel. The mouth of B. caudomaculatus was relatively upturned, whereas the mouth of B. wavrini was relatively subterminal, in channel habitats. Observed morphological patterns are consistent with functional morphological principles suggesting adaptive divergence. We also show that spatial distance between habitats, presumably reflecting rates of population mixing, appears to have constrained diversification. For both species, morphological divergence increased with distance between habitats. Thus morphological divergence between channel and lagoon habitats apparently reflects a balance between diversification driven by natural selection, and homogenization driven by population mixing.

Author-supplied keywords

  • Biotodoma wavrini Bryconops caudomaculatus Characi

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

There are no full text links


  • R B Langerhans

  • C A Layman

  • A K Langerhans

  • T J Dewitt

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free