Open AccessMolecular systematics and patterns of morphological evolution in the Centropagidae (Copepoda: Calanoida) of Argentina
Author(s) -
ADAMOWICZ SARAH J.,
MENUMARQUE SILVINA,
HEBERT PAUL D. N.,
PURVIS ANDY
Publication year - 2007
Publication title -
biological journal of the linnean society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.906
H-Index - 112
eISSN - 1095-8312
pISSN - 0024-4066
DOI - 10.1111/j.1095-8312.2007.00723.x
Subject(s) - biology , systematics , calanoida , evolutionary biology , taxon , taxonomy (biology) , genetic divergence , genetic diversity , zoology , species complex , divergence (linguistics) , ecology , crustacean , phylogenetic tree , gene , genetics , copepod , population , linguistics , demography , philosophy , sociology
Recent studies have shown the value of complementing standard taxonomy with genetic analyses to reveal cryptic diversity and to aid in the understanding of patterns of evolution. We surveyed variation in the COI mitochondrial gene in members of the three genera of centropagid copepods from the inland waters in Argentina. In general, we found a close association between molecular and morphological systematics in this group. Similar to findings for marine calanoids, genetic distances within Boeckella species were modest (< 4%), while distances among morphospecies were much larger (> 11%). Parabroteas is currently monotypic, although we detected cryptic genetic diversity, with two lineages showing 5.5% divergence. In contrast, Karukinka was not a valid genus, apparently representing an interesting and atavistic offshoot of B. poppei , a result reinforcing the value of considering both morphological and molecular evidence. Moreover, we used combined genetic and morphological information, analysed with maximum likelihood methods, to evaluate the common assumption that evolution tends to proceed via the loss of structures in crustaceans. Although analysis of other taxa and character types is required to evaluate fully the reduction hypothesis, our results suggest that structures may be gained readily as well as lost. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 90 , 279–292.