The Frog-Biting Midges of the World (Corethrellidae: Diptera)

Abstract

This worldwide biosystematic study of Corethrellidae, with its single genus Corethrella Coquillett, provides a complete compilation of all that is known for the group, both taxonomically and bionomically. Descriptions of each species are based primarily on the adults, summarize all bionomic information, and provide a map showing its distribution. Keys to the species of each region are provided. A total of 97 extant species is recognized, with 52 of these being new. Seven fossil species are described with two of these being new to science. All species, including 13 new synonyms, are cataloged in a table for easy reference. Seven extant species are of uncertain status because of damaged or missing types. Lectotypes and, depending on the species, some paralectotypes, are designated for the following species: C. inepta (Annandale), C. pallitarsis Edwards, C. picticollis Edwards, C. ananacola Dyar, C. calathicola Edwards, and C. brakeleyi (Coquillett). A cladistic analysis interprets most extant and fossil species (some are not interpretable at the present time) and provides the basis for zoogeographic and bionomic interpretation. Worldwide, Corethrella species are found between 50°N and 50°S but most are found between 30°N and 30°S and below 1500 meters in elevation. Because female adults are attracted to the call of male frogs and feed on their blood, species are restricted to areas where there are frogs. Phylogenetic patterns suggest Gondwanan connections for earlier lineages within the genus. At least one lineage has dispersed from the New World to southeast Asia and some species are located on volcanic islands in the Caribbean, indicating further instances of dispersal. It is certain that many more species are yet to be discovered. Phylogenetic patterns indicate that the immatures of Corethrella species have repeatedly moved between ground-dwelling habitats and phytotelmata, with the plesiotypic habitat likely being ground-dwelling. Some lineages have diversified within phytotelmata. Fossil, cladistic and morphological evidence indicates that Corethrella females have been feeding on calling frogs since at least the Early Cretaceous. Females likely hear their frog hosts using the Johnston’s Organ. There is some evidence of host specificity as well as selection of particular biting sites for some species of Corethrella. The females of at least some species of Corethrella transmit Trypanosoma Gruby between calling frogs and this association is also likely an ancient one.Este estudio biosistemático de Corethrellidae a nivel Mundial, con su único género Corethrella, proporciona una completa recopilación de todo lo conocido para el grupo, tanto desde el punto de vista taxonómico como bionómico. Las descripciones de cada especie se realizan primariamente sobre la base de adultos, resumen toda la información bionómica y proveen un mapa donde se muestra su distribución. Se brindan claves para especie de cada región. Se reconoce un total de 97 especies, 52 de las cuales son nuevas. Se describen siete especies fósiles, siendo dos de ellas nuevas para la Ciencia. Para una fácil referencia, todas las especies son catalogadas en una tabla, incluyendo 13 nuevos sinónimos. Debido a que sus tipos se hallan dañados o perdidos, siete especies actuales ostentan un status incierto. De acuerdo a la especie, son designados lectotipos o paralectotipos de las siguientes especies: C. inepta (Annandale), C. pallitarsis Edwards, C. picticollis Edwards, C. ananacola Dyar, C. calathicola Edwards, y C. brakeleyi (Coquillett). El análisis cladístico interpreta la mayoría de las especies actuales y fósiles (algunas no pueden ser interpretadas actualmente) y provee la base para interpretaciones zoogeográficas y bionómicas. Las especies de Corethrella se hallan entre 50°N y 50°S, aunque la mayoría se encuentran entre 30°N y 30°S y por debajo de 1500 metros de elevación. Debido a que las hembras adultas son atraídas por el llamado de ranas macho y se alimentan de su sangre, las especies están restringidas a las áreas donde se hallan ranas. Los patrones filogenéticos sugieren conecciones Gondwánicas para los linajes más antiguos del género. Al menos un linaje se ha dispersado desde el Nuevo Mundo hacia el sudeste de Asia, y algunas especies se hallan en islas volcánicas del Caribe, indicando otras instancias de dispersión. Con seguridad aún quedan muchas más especies por ser descubiertas. Los patrones filogenéticos indican que los inmaduros de las especies de Corethrella se han movido repetidamente entre habitats ubicados a nivel del suelo y fitotelmata, siendo probablemente

Acoustic localisation of frog hosts by blood‐sucking flies Corethrella Coquillet (Diptera: Corethrellidae) in Borneo

“…This will be true in particular for rainforest environments with their exceptionally high richness of host species (Grafe & Keller in press). The diversity of Corethrella in peatswamp habitats of Brunei Darussalam, although only incompletely surveyed, is comparable to that in other habitats (Borkent 2008).…”

“…None of the morphotypes matched current descriptions of Corethrella from SE-Asia (Colless 1994;Borkent 2008). DNA sequencing of morphotypes suggests that they represent individual species with only a very few cases of mistaken classification (R Meier pers.…”

“…Very little is known about this group of flies because insect collectors using light traps, Malaise traps, or aerial nets rarely encounter them. In Australasia, so far, only a few species of frog-biting midges have been described (Colless 1986(Colless , 1994Borkent 1993Borkent , 2008.…”

Biodiversity of Biting Flies: Implications for Humanity

“…About 100 species are currently recognized (Borkent 2008), with estimates of more than twice that number still awaiting discovery (A. Borkent, personal communication).…”

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)

“…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).…”