Mitochondrial DNA reveals monophyly of New Zealand's Gobiomorphus (Teleostei: Eleotridae) amongst a morphological complex

作者：Stevens Mark I^*; Hicks Brendan J

来源：Evolutionary Ecology Research, 2009, 11(1): 109-123.

• amphidromy
• Gobiomorphus
• habitat fragmentation
• island systems
• mtDNA (Cyt-b)
• species radiation

Goal: To examine the phylogenetic relationships within Gobiomorphus to explore Australasian biogeography, origins (single or multiple), and evolutionary loss of a marine life stage (loss of diadromy).
Methods: We analyse a fragment of the mitochondrial DNA (Cyt-b) using phylogenetic analyses, and use several meristics (spines, rays, and vertebrae) in a discriminant function analysis.
Organisms: All nine species of the genus Gobiomorphus (Eleotridae) found in New Zealand and Australia, with the two Australian Philypnodon species included as outgroup taxa.
Conclusions: Monophyly of the genus and all seven New Zealand species was strongly supported. The New Zealand Gobiomorphus are likely to be the result of a single introduction and to have been isolated from Australia since the Miocene or Pliocene (similar to 18-28 Myr ago). These dates correspond well to the oldest fossil in New Zealand dated at 16-20 Myr. Diadromy was consistently at the root of the New Zealand group, and non-diadromy and morphological diversification among these species appears to have occurred relatively recently, with meristic comparisons supporting the molecular analyses. However, among the non-diadromous forms, species morphology contrasts with the molecular data Suggesting a recent evolutionary history driven by ecological selection.

• 出版日期2009-1