Abstract
The Acontinae is a well-supported clade of limbless skinks from sub-Saharan Africa for which three fossorial genera⎯Acontias, Acontophiops, and Typhlosaurus⎯have been traditionally recognized. However, recent phylogenetic analyses demonstrate conflicting support for the monophyly of Acontias and Typhlosaurus, despite limited taxon sampling for the latter genus. We re-investigate acontine evolutionary relationships, including all currently recognized species of Typhlosaurus, in phylogenetic analyses of mitochondrial (Cytb, Co1, 16s) and nuclear (Rag1) gene sequences. Our results show that Typhlosaurus is polyphyletic and represented in three distinct clades, one of which constitutes the sister lineage to other acontines. The remaining typhlosaurs form strongly-supported clades with either Acontophiops or the recently-described genus Microacontias (formerly Acontias lineatus and A. litoralis). We use this new phylogenetic framework to revise acontine taxonomy. Typhlosaurus is restricted to five species from southwestern Africa, all characterized by an attenuate body form. Acontias is expanded to include the former T. aurantiacus, T. cregoi, and T. lineatus groups as well as Acontophiops and Microacontias. Species transfer between acontine genera created two secondary homonyms; thus the affected taxa are assigned replacement names.References
Bates, M.F., Heideman, N.J.L., Wilson, B.A., Hendricks, M.G.J., Don, N. & Moses, C. (1999) Morphological variation and geographical distribution in the South African lizards Typhlosaurus caecus (Cuvier 1817) and Typhlosaurus vermis Boulenger 1887 (Scincidae: Acontinae). African Journal of Herpetology, 47 [1998], 35–41.
Bauer, A.M., Schneider, V., Lamb, T., Moler, P.E. & Babb, R.D. (2000) New data on the South African skink Typhlosaurus lomii Haacke 1986 (Squamata: Scincidae). African Journal of Herpetology, 48 [1999], 21–25.
Bickham, J.W., Lamb, T., Minx, P. & Patton, J.C. (1996) Molecular systematics of the genus Clemmys and the intergeneric relationships of emydid turtles. Herpetologica, 52, 89–97.
Boulenger, G.A. (1887) Catalogue of the Lizards in the British Museum (Natural History), Vol. III. Trustees of the British Museum (Natural History), London, xii+575 pp., 40pls.
Branch, B. (1998) Field Guide to Snakes and Other Reptiles of Southern Africa, 3rd ed., Ralph Curtis Books Publishing, Florida, 399 pp.
Brandley, M.C., Schmitz, A. & Reeder, T.W. (2005) Partitioned Bayesian analyses, partition choice, and phylogenetic relationships of scincid lizards. Systematic Biology, 54, 373–390.
Broadley, D.G. (1968) A revision of the African genus Typhlosaurus Wiegmann (Sauria: Scincidae). Arnoldia, 3(36), 1–20.
Broadley, D.G. (1990) The herpetofaunas of the islands off the coast of South Mocambique. Arnoldia Zimbabwe, 9, 469–493.
Broadley, D.G. & Greer, A.E. (1969) A revision of the genus Acontias Cuvier (Sauria: Scincidae). Arnoldia, 4(26), 1–27.
Crottini, A., Dordel J., Kohler, J., Glaw, F. Schmitz, A. & Vences, M. (2009) A multilocus phylogeny of Malagasy scincid lizards elucidates the relationships of the fossorial genera Androngo and Cryptoscincus. Molecular Phylogenetics and Evolution, 53, 345–350.
Daniels, S.R., Heideman, N.J.L. & Hendricks, M.G.J. (2009) Examination of evolutionary relationships in the Cape fossorial skink species complex (Acontinae: Acontias meleagris meleagris) reveals the presence of five cryptic lineages. Zoologica Scripta, 38, 449–463.
Daniels, S.R., Heideman, N.J.L., Hendricks, M.G.J. & Wilson, B.A. (2002) A molecular phylogeny for the South African limbless lizard taxa of the subfamily Acontinae (Squamata: Scincidae) with special emphasis on relationships within Acontias. Molecular Phylogenetics and Evolution, 24, 315–323.
Daniels, S.R., Heideman, N.J.L., Hendricks, M.G.J., Mokone, M.E. & Crandall, K.A. (2005) Unraveling evolutionary lineages in the limbless fossorial skink genus Acontias (Sauria: Scincidae): are subspecies equivalent? Molecular Phylogenetics and Evolution, 34, 645–654.
Daniels, S.R., Heideman, N.J.L., Hendricks, M.G.J. & Crandall, K.A. (2006) Taxonomic subdivisions within the fossorial skink subfamily Acontinae (Squamata:Scincidae) reconsidered: a multilocus perspective. Zoologica Scripta, 35, 353–362.
De Witte, G.F. & Laurent, R. (1943) Contribution a la systématique des formes dégradées apparentées au genre Scelotes Fitzinger. Mémoires du Musée Royal D’Histoire Naturelle de Belgique, 26, 1–42.
Fitzsimons, V.F. (1943) The Lizards of South Africa. Memoirs of the Transvaal Museum, 1, i–xv + 1–528, + 24 pls + map.
Greer, A.E. (1970) A subfamilial classification of scincid lizards. Bulletin of the Museum of Comparative Zoology 139, 151–184.
Greer, A.E. (1991) Limb reduction in squamates: identification of the lineages and discussion of the trends. Journal of Herpetology, 25, 166–173.
Haacke, W.D. (1986) Description of a new species of Typhlosaurus Wiegmann, 1834 (Reptilia: Scincidae) from the west coast of southern Africa, with new records of related species. Annals of the Transvaal Museum, 34, 227–235.
Hewitt, J. (1937) A Guide to the Vertebrate Fauna of the Eastern Cape Province, South Africa, Part II: Reptiles, Amphibians, and Freshwater Fishes. Albany Museum, Grahamstown.
Huelsenbeck, J.P. & Ronquist, F. (2001) MrBayes: Bayesian inference of phylogeny. Bioinformatics, 17, 754–755.
Jacobsen, N.H.G. (1987) A new subspecies of Typhlosaurus lineatus Boulenger 1887 (Reptilia: Scincidae) from Venda, southern Africa. South African Journal of Zoology, 22, 318–320.
Kass, R.E. & Raftery, A.E. (1995) Bayes factors. Journal of American Statistical Association, 90, 773–795.
Kearny, M. & Stuart, B.L. (2004) Repeated evolution of limblessness and digging heads in worm lizards revealed by DNA from old bones. Proceedings of the Royal Society, London B, 27, 1677–1683.
Kim, Y.J., Gorman, G.C. & Huey, R.B. (1978) Genetic variation and differentiation in two species of the fossorial African skink Typhlosaurus (Sauria: Scincidae). Herpetologica, 34,192–194.
Köhler, J., Vences, M., Erbacher, M. & Glaw, F. (2010) Systematics of limbless scincid lizards from northern Madagascar: morphology, phylogenetic relationships and implications for classification (Squamata: Scincidae). Organisms, Diversity & Evolution, 10, 147–159.
Lamb, T. & Bauer, A.M. (2006) Footprints in the sand: independent reduction of subdigital lamellae in the Namib-Kalahari burrowing geckos. Proceedings of the Royal Society, London B, 273, 855–864.
Luke, C. (1986) Convergent evolution of lizard toe fringes. Biological Journal of the Linnean Society, 27, 1–16.
Michels, J.P. & Bauer, A.M. (2004) Some corrections to the scientific names of amphibians and reptiles. Bonner zoologische Beiträge, 52, 83–94.
Mott, T. & Vieites, D.R. (2009) Molecular phylogenetics reveals extreme morphological homoplasy in Brazilian worm lizards challenging current taxonomy. Molecular Phylogenetics and Evolution, 51, 90–200.
Rambaut, A. & Drummond, A.J. (2009) Tracer, MCMC Trace Analysis Package Version 1.5 ed., University of Oxford, Rambaut Research Group.
Reeder, T.W. (2003) A phylogeny of the Australian Sphenomorphus group (Scincidae: Squamata) and the phylogenetic placement of the crocodile skinks (Tribolonotus): Bayesian approaches to assessing congruence and obtaining confidence in maximum likelihood inferred relationships. Molecular Phylogenetics and Evolution, 27, 384–397.
Rieppel, O. (1981) The skull and jaw adductor musculature in some burrowing scincomorph lizards of the genera Acontias, Typhlosaurus, and Feylinia. Journal of Zoology (London), 195, 493–528.
Rieppel, O. (1982) The phylogenetic relationships of the genus Acontophiops Sternfeld (Sauria: Scincidae), with a note on mosaic evolution. Annals of the Transvaal Museum, 33, 241–257.
Rieppel, O. (1984a) Miniaturization of the lizard skull: its functional and evolutionary implications. In: Ferguson, M.W.J. (Ed.), The Structure, Development and Evolution of Reptiles. Academic Press, Orlando, pp. 503–520.
Rieppel, O. (1984b) The upper temporal arcade of lizards: an ontogenetic problem. Revue Suisse de Zoologie, 91, 475–482.
Ronquist, F. & Huelsenbeck, J.P. (2003) MrBayes 3: Bayesian phylogenetic inference of under mixed models. Bioinformatics, 19, 1572–1574.
Schmitz, A., Brandley, M.C., Mausfeld, P., Vences, M., Glaw, F., Nussbaum, R.A. & Reeder, T.W. (2005) Opening the black box: phylogenies and morphological evolution of the Malagasy fossorial lizards of the subfamily “Scincinae.” Molecular Phylogenetics and Evolution, 34, 118–133.
Schneider, V. (2001) A phylogenetic and biogeographic analysis of Typhlosaurus (Squamata: Scincidae: Acontinae). M.S. Thesis, Villanova University.
Schneider, V. & Bauer, A.M. (2009) Typhlosaurus jappi Broadley, 1968, a valid species of acontine skink. African Journal of Herpetology, 58, 56–58.
Skinner, A., Lee. M.S.Y. & Hutchison, M.N. (2008) Rapid and repeated limb loss in a clade of scincid lizards. BMC Evolutionary Biology, 8, 310.
Swofford, D.L. (2002) PAUP*. Phylogenetic analysis using parsimony (*and other methods), Version 4.0 b10. Sinauer Associates, Sunderland, MA.
Tanabe, A.S. (2007) Kakusan: a computer program to automate the selection of a nucleotide substitution model and the configuration of a mixed model on multilocus data. Molecular Ecology Notes, 7, 962–964.
Thompson, J.D., Gibson, T.J., Plewniak, F., Jeanmougin, F. & Higgins, D.G. (1997) The CLUSTAL X windows interface: flexible strategies for multiple sequence alignment aided by quality analysis tools. Nucleic Acids Research, 24, 4876–4882.
Welch, K.R.G. (1982) Herpetology of the Old World II. Preliminary comments on the classification of skinks (Family Scincidae) with specific reference to those genera found in Africa, Europe and Southwest Asia. Herptile, 7(4), 25–27.
Whiting, A.S., Bauer, A.M. & Sites, J.W., Jr. (2003) Phylogenetic relationships and limb loss in sub-Saharan African scincine lizards (Squamata: Scincidae). Molecular Phylogenetics and Evolution, 29, 582–598.
Whiting, A.S., Sites, J.W., Jr. & Bauer, A.M. (2004) Molecular phylogenetics of Malagasy skinks (Squamata: Scincidae). African Journal of Herpetology, 53, 135–146.
Wiens, J.J., Brandley, M.C. & Reeder, T.W. (2006) Why does a trait evolve multiple times within a clade? Repeated evolution of snake-like body form in squamate reptiles. Evolution, 60, 123–141.
Zwickl, D.J. (2006) Genetic algorithm approaches for the phylogenetic analysis of large biological sequence datasets under the maximum likelihood criterion. Ph.D. dissertation, The University of Texas at Austin.