Species-specific communication bars interspecific mating between syntopic species ofZwickniastoneflies (Plecoptera: Capniidae)

Abstract

Most Northern Hemisphere stoneflies have species-specific mating signals that are generally thought to constitute a barrier against interspecific mating. We tested this hypothesis in two species of the genus Zwicknia that have only very recently been recognised as distinct species, and that were found to occur together in a stream in Lower Saxony, Germany. Analyses of molecular markers COI and 28S in combination with wing length (distinguishing males of both species) and mating signals revealed no instance of hybridisation among 23 studied specimens. In addition, eleven further males identified on the basis of morphology alone all produced the expected species-specific signal. Females and males of both species were presented with played back conspecific and heterospecific signals and duetting sequences, and responded only to conspecific stimuli. This lends support to the hypothesis that the intersexual communication system functions as an important pre-mating barrier against gene flow, although post-mating isolation cannot be excluded. Interspecific mating did occur when a mixed pair was confined together in a small container. Males of both species were found to call in response to played back duetting sequences with stereotypic latencies that are clearly longer than the latencies in male-female duets. We interpret this as an indication of eavesdropping behaviour coupled with attempts to take over the perceived duet.

Female answer specificity to male drumming calls in three closely related species of the stonefly genus Zwicknia (Plecoptera: Capniidae)

“…3A, B). Between those species, the vibrational signal based heterospecific discrimination is as clear‐cut as that reported between Z. bifrons and Z. westermanni Boumans & Murányi by Boumans and Johnsen (2014). Our results about the mutual, strong discrimination of heterospecific calls in Z. bifrons and Z. rupprechti are in accordance with Rupprecht's results (1965, 1968, 1982), who found during playback trials that both Z. rupprechti and Z. bifrons females answered artificial stimuli with the highest answer ratio when the interbeat interval and duration of stimuli matched the species‐specific range of those characters.…”

“…If a female finds the male signal appropriate, she answers with her own vibrational signal and becomes stationary and the male finds her by vibrotaxis, or in some species she also moves toward the male (Rupprecht, 1968). Male signals and male‐female vibrational duet patterns are described in a large number of species, but there are only a handful of studies presenting experimental results about female answer specificity to male calls (Rupprecht, 1965, 1968, 1982; Zeigler & Stewart, 1986; Stewart & Maketon, 1990; Boumans & Johnsen, 2014).…”

Integrative taxonomy refutes a species hypothesis: The asymmetric hybrid origin of Arsapnia arapahoe (Plecoptera, Capniidae)

“…That hybridization might be more prevalent is discouraged by the biological species concept with its predisposition to view hybridization as a rare accident (Mallet, ) and by notions that behavioral or anatomical differences constitute intrinsic reproductive barriers. For example, conspecific drumming signals used by male and female stoneflies for mate recognition are regarded as species‐specific and likely to ensure pre‐zygotic reproductive isolation (Boumans & Johnsen, ; Stewart, ). Nonetheless, there are many examples of arthropod taxa with elaborate pre‐mating and putatively species‐specific displays that nonetheless result in attempted mating between species (Masly, ), including between stoneflies in different genera (Zeigler, ).…”

Male–male interactions and male mating success in the leafhopper Aphrodes makarovi

“…So far, female preferences in duetting systems based on substrate‐borne vibrational signals have been mainly studied in the context of mate recognition associated with pre‐mating reproductive isolation, where females preferentially respond to vibrational signals emitted by conspecific males (e.g., Boumans & Johnsen, ; Derlink, Pavlovčič, Stewart, & Virant‐Doberlet, ; Noh & Henry, ; Rodríguez, Ramaswamy, & Cocroft, ; Rodríguez, Sullivan, & Cocroft, ). However, much less is known about male mating success in situations that include male–male competition, where more detailed information is limited to three species, treehoppers Enchenopa binotata (Sullivan‐Beckers & Cocroft, ) and Tylopelta gibbera (Legendre, Marting, & Cocroft, ) and the leafhopper Scaphoideus titanus (Mazzoni, Prešern, Lucchi, & Virant‐Doberlet, ).…”

“…So far, female preferences in duetting systems based on substrateborne vibrational signals have been mainly studied in the context of mate recognition associated with pre-mating reproductive isolation, where females preferentially respond to vibrational signals emitted by conspecific males (e.g., Boumans & Johnsen, 2014;Derlink, Pavlovčič, Stewart, & Virant-Doberlet, 2014;Noh & Henry, 2010;Rodríguez, Ramaswamy, & Cocroft, 2006;Rodríguez, Sullivan, & Cocroft, 2004).…”