Is millipede taxonomy based on gonopod morphology too inclusive? Observations on genetic variation and cryptic speciation in Bicoxidens flavicollis (Diplopoda: Spirostreptida: Spirostreptidae)

T. Mwabvu, J. Lamb, R. Slotow, M. Hamer, D. Barraclough

Abstract


The structure of the male gonopods of millipedes has been considered to be species-specific. As such, go­nopods—which aid in copulation and sperm transfer—are used in the taxonomic diagnosis and de­scrip­tion of species. However, it was recently demonstrated that gonopod morphology is not always cha­rac­teristic of species. Diagnoses based on gonopod morphology can therefore result in underestimation of ta­xonomic diversity amongst millipedes. On the basis of this observation, we examined genetic variation in two populations (approximately 250 km apart) of a widely distributed and colour-polymorphic southern Af­rican millipede, namely Bicoxidens flavicollis Attems, 1928. An analysis of genetic divergence based on 520 nucleotides of the mitochondrial cytochrome oxidase 1 gene, and 684 nucleotides of the mitochondrial 16S rRNA gene, demonstrated high levels of divergence (19.09 % for cytochrome oxidase 1 and 6.66 % for 16S rRNA) between the two populations. These results suggest the presence of cryptic species in B. fla­vicollis and, furthermore, corroborate observations that taxonomy based on gonopod morphology may be too inclusive.

To cite this paper: Mwabvu, T., Lamb, J., Slotow, R., Hamer, M. & Barraclough, D. 2013. Is millipede taxonomy based on gonopod morphology too inclusive? Observations on genetic variation and cryptic speciation in Bicoxidens flavicollis (Diplopoda: Spirostreptida: Spirostreptidae). African Invertebrates 54 (2): 349–356.

Published electronically: 14 August 2013
urn:lsid:zoobank.org:pub:1BD03DEB-501E-4EF6-A0B8-A26A7AC99D36


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