Confusion and isolation in the courtship of two sympatric and synchronic tarantula spiders (Mygalomorphae, Theraphosidae)

摘要

Strong reproductive barriers are expected between similar species that co-occur in time and space. We experimentally analysed sexual interactions between the theraphosids Acanthoscurria suina and Eupalaestrus weijenberghi which met those conditions. Unexpectedly, males courted on heterospecific female cues. Furthermore, A. suina females seemed to be more receptive to heterospecific males than conspecific ones in early courtship. Although precopulatory confusion occurred, no interspecific copulationswere observed, which indicate that reproductive barriers operate.