03440nas a2200373   4500008004100000020001400041245016600055210006900221260001200290300001200302490000800314520221100322653002302533653002602556653002702582653002902609653002802638653001602666653003602682653002402718653001802742653002302760653002702783653002802810653002202838653001902860653002602879653001502905100002402920700002502944700002202969700002102991856005403012       2008                        eng d  a0928-425700aPetrocephalus of Odzala offer insights into evolutionary patterns of signal diversification in the Mormyridae, a family of weakly electrogenic fishes from Africa0 aPetrocephalus of Odzala offer insights into evolutionary pattern  cJul-Nov  a322-3390 v1023 a<p>Electric signals of mormyrid fishes have recently been described from several regions of Africa. Members of the Mormyridae produce weak electric organ discharges (EODs) as part of a specialized electrosensory Communication and orientation system. Sympatric species often express distinctive EODs, which may contribute to species recognition during mate choice in some lineages. Striking examples of interspecific EOD variation within assemblages have been reported for two monophyletic radiations: the Paramormyrops of Gabon and the Campylomormyrus of Lower Congo. Here, we describe a speciose assemblage of Petrocephalus in the Lekoli River system of Odzala National Park, Republic of Congo. This widespread genus comprises the Subfamily (Petrocephalinae) that is the Sister group to all other mormyrids (Mormyrinae). Eleven Petrocephalus species were collected in Odzala, five of which are not described taxonomically. We quantify EOD variation within this assemblage and show that all eleven species produce EOD waveforms of brief duration (species means range from 144 to 663 mu s) compared to many other mormyrids. We also present reconstructed phylogenetic relationships among species based on cytochrome b sequences. Discovery of the Odzala assemblage greatly increases the number of Petrocephalus species for which EODs and DNA sequence data are available, permitting a first qualitative comparison between mormyrid Subfamilies of the divergence patterns that have been described within lineages. We find that the Petrocephalus assemblage in Odzala is not a monophyletic radiation. Genetic divergence among Petrocephalus species often appears higher than among Paramormyrops or Campylomormyrus species. In contrast, results of this study and others Suggest that Petrocephalus may generally exhibit less interspecific EOD divergence, as well as smaller sex differences in EOD waveforms, compared to Paramormyrops and Campylomormyrus. We discuss possible causes and consequences of EOD diversification patterns observed within mormyrid subfamilies as a framework for future comparative studies of signal evolution using this emerging model system. (c) 2008 Elsevier Ltd. All rights reserved.</p>
10aadaptive radiation10acommunication signals10aelectric organ anatomy10aelectric organ discharge10aelectrosensory modality10afood-habits10agnathonemus-petersii mormyridae10amolecular evolution10apetrocephalus10apollimyrus-isidori10ariverine species flock10asexual signal evolution10asexual-dimorphism10aspecies marker10atype npp electrocytes10awave-forms1 aLavoué, Sébastien1 aArnegard, Matthew, E1 aSullivan, John, P1 aHopkins, Carl, D  u https://doi.org/10.1016/j.jphysparis.2008.10.003