Hematophagous Flies Attracted to Frog Calls in a Preserved Seasonal Forest of the Austral Neotropics, with a Description of a New Species of Corethrella (Diptera: Corethrellidae)

Abstract

The signaler-eavesdropper interaction has been investigated for a wide range of organisms, and although many flies feed on calling frogs, this dynamic has been addressed only poorly in the austral Neotropics. We investigated this interaction in southern Brazil using pairs of suction traps (acoustic + silent) broadcasting frog calls or an artificial white noise in ponds and streams. From 139 sessions, flies of the genera Corethrella (Corethrellidae), Forcipomyia (Ceratopogonidae) and Uranotaenia (Culicidae) were collected, including five Corethrella species, the most abundant of which was previously unknown and is formally described here. Additionally, we present the southernmost records of Corethrella lopesi, C. alticola and C. atricornis. Numbers of Forcipomyia midges and Uranotaenia mosquitoes did not differ between silent traps and traps broadcasting frog calls, and did not differ between white noise traps and adjacent silent traps. However, the number of female Corethrella was significantly higher in traps broadcasting calls of the pond-breeding frog P. aff. gracilis compared to adjacent silent traps; calls of this frog attracted the five Corethrella species and also collected significantly more female Corethrella than the white noise. By evaluating different taxa of flies and broadcasting different sounds, we demonstrated that Corethrella midges were attracted only to the acoustic cue of P. aff. gracilis calls, while Forcipomyia and Uranotaenia were captured in traps by chance. Our results suggest that female Corethrella feed on males of the common pond-breeding frog P. aff. gracilis in southern Brazil, and highlight the utility of frog call traps in revealing the diversity of Corethrella in the austral Neotropics.

The sound of a blood meal: Acoustic ecology of frog‐biting midges (Corethrella) in lowland Pacific Costa Rica

“…The preferred frequency bandwidth found in the midges from La Gamba was 200–650 Hz, with an effective upper threshold at ~4 kHz. Similar upper limits to hearing have been found in frog‐biting midges from southern Brazil (Caldart, Santos, Iop, Pinho, & Cechin, ) and Borneo (Meuche et al, ). Frog‐biting midges were not attracted to continuous tones (>16 s) but clearly required pulsed auditory stimulation (on–off patterns) with very short inter‐pulse durations of down to 5 ms being sufficient for stimulus recognition.…”

“…The attractiveness of recorded natural calls varied greatly, as it has been shown in previous studies (Borkent, ; Caldart et al, ; McKeever & French, ; Meuche et al, ), suggesting a selective perception or preference for certain call characteristics. The advertisement call of the Giant Bullfrog ( L. savagei ) was most attractive to frog‐biting midges, more than an order of magnitude more attractive than the calls of other frogs.…”

“…The attractiveness of recorded natural calls varied greatly, as it has been shown in previous studies (Borkent, 2008;Caldart et al, 2016;McKeever & French, 1991;Meuche et al, 2016), suggesting a selective perception or preference for certain call characteristics.…”

A new species of frog-biting midge from Papua New Guinea with a key to the described Corethrellidae of the Australopapuan region (Diptera, Corethrellidae, Corethrella)

“…Their fossil record extends back to the early Cretaceous and their ancient age is reflected in their biogeography which suggests Gondwanan vicariate events (Borkent 2008, Baranov et al 2016). Including the new species described herein, 110 species are known from the extant fauna; however, this family has received little taxonomic study across their broad worldwide distribution (Borkent 2008, Borkent and Grafe 2012, Fei-peng et al 2015, Baranov et al 2016, Caldart et al 2016). …”

“…Locating their hosts primarily by auditory cues (Borkent 2008, Bernal and de Silva 2015), they are an emerging study system in studying the ecology and evolution of acoustic eavesdropping behaviour (Bernal et al 2006, Grafe et al 2008, 2018, de Silva et al 2015, Caldart et al 2016, Legett et al 2018). Their fossil record extends back to the early Cretaceous and their ancient age is reflected in their biogeography which suggests Gondwanan vicariate events (Borkent 2008, Baranov et al 2016).…”