Hybridisation of tree weta on banks peninsula, new zealand, and colour polymorphism within hemideina ricta (Orthoptera: Stenopelmatidae)

Abstract

The two species of tree weta on Banks Peninsula, New Zealand, Hemideina ricta and H. femorata, are genetically distinct though morphologically similar. Our allozyme data coincide with species identification based on numbers of stridu- latory ridges. However, H. ricta appears to be polymorphic for the presence of black markings on hind femora and abdominal tergites. At one location on Banks Peninsula, weta were collected that were heterozygous at all 11 loci that differ between H. ricta and those of H. femorata. The numbers of stridulatory ridges on these two individuals fall between those characterising H. ricta and H. femorata. We conclude that these two weta are first generation hybrids, and that the detection of only FI hybrids suggests that they are probably sterile. Sex-linkage of phosphoglucomutase is found to be conserved in this family. © 1995 Crown.