Belontiidae chemosignal activity: interspecific attraction and perceived chemosignal similarity

Abstract

Belontiidae chemical communicatory substances were examined for interspecific behavioral activity. In Experiment 1, male Betta were exposed to ripe-female-conditioned water (RFCW) from either the goldfish (Carassius auratus) or one of the following Belontiidae species: (a) Betta splendens, (b) Colisa labiosa, (c) Colisa lalia, (d) Macropodus opercularis, or (e) Trichogaster trichopterus. Time spent near and within a stimulus source tube was used to measure the chemosignal activity for each species. Both behavioral measures showed evidence for interspecific chemocommunication. The proximity measure indicated a phylogenetically nonspecific chemosignal, whereas tube occupancy indicated the presence of a specific Belontiidae system. Experiment 2 was a stimulus generalization test using a psychophysical paradigm. Male Betta were trained to discriminate Betta RFCW from Carassius RFCW, and were subsequently presented with RFCW from either (a) C. lalia, (b) M. opercularis, (c) T. trichopterus, and (d) P. reticulata. The latter were novel stimulus generalization chemosignals. The male Betta perceived Belontiidae RFCW stimuli as similar, whereas guppy RFCW was neither perceived as Belontiidae nor Carassius RFCW. Thus, Belontiidae chemosignals may be similar in structure due to a common phylogenetic ancestry.