A phylogenetic analysis of variation in reproductive mode within an Australian lizard (Saiphos equalis, Scincidae) |
| |
Authors: | SARAH A. SMITH CHRISTOPHER C. AUSTIN RICHARD SHINE |
| |
Affiliation: | Herpetology Section, Australian Museum, 6 College Street, Sydney, New South Wales 2000, Australia;School of Biological Sciences A08, University of Sydney, New South Wales 2006, Australia;Evolutionary Biology Unit, Australian Museum, 6 College Street, Sydney, New South Wales 2000, Australia;Department of Biology, University of North Dakota, Grand Forks, North Dakota, USA |
| |
Abstract: | Saiphos equalis , a semi-fossorial scincid lizard from south-eastern Australia, is one of only three reptile species world-wide that are known to display geographic variation in reproductive mode. Uniquely, Saiphos equalis includes populations with three reproductive modes: oviparous with long (15-day) incubation periods; oviparous with short (5-day) incubation periods; and viviparous (0-day incubation periods). No Saiphos populations show 'normal' scincid oviparity (> 30-day incubation period). We used mitochondrial nucleotide sequences ( ND2 and cytochrome b ) to reconstruct relationships among populations from throughout the species' distribution in New South Wales, Australia. Under the phylogenetic species concept, phylogenetic analyses are consistent with the oviparous and viviparous populations of S. equalis being conspecific. Phylogenetic analyses suggest that the long incubation period oviparous lineage is the sister group to all other populations; and that the viviparous populations belong to a cluster of weakly supported clades basal to the short-incubation-period oviparous clade. These clades correspond to variation in reproductive mode and geographic location. |
| |
Keywords: | viviparity Scincidae reproductive mode phylogeny reptiles Australian lizards |
|
|