Madagopsina gen. n. and Gracilopsina gen. n. (Diptera: Diopsidae) from Madagascar with description of four new species

Abstract

Madagopsinagen. n. andGracilopsinagen. n. are described as endemic Diopsidae taxa for Madagascar. Three Madagascan Diopsidae, earlier alternately placed inDiopsis,EurydiopsisorCyrtodiopsis(also asTeleopsis), are now referred toMadagopsinagen. n., while two of these three species proved to be conspecific. This gives rise toMadagopsina apollo(Brunetti) comb. n. andMadagopsina apographica(Séguy) comb. n. =anjahanaribei(Vanschuytbroeck) syn. n. The two species are redescribed.Madagopsina apographicaproved to have a mixed type series. Three new species are allocated to the genus asMadagopsina freidbergisp. n.,Madagopsina parvapollinasp. n. andMadagopsina tschirnhausisp. n. ForEurydiopsis vadoniVanschuytbroeck (later also placed inCyrtodiopsisandTeleopsis) the genusGracilopsinagen. n. is erected, leading toGracilopsina vadoni(Vanschuytbroeck) comb. n.Gracilopsina vadoniis redescribed and is shown to have a mixed type series. One new species is allocated to the genus asGracilopsina sinespinasp. n. A key is presented to the two genera and seven species. Madagascar now counts five Diopsidae genera and 12 species, of which two genera and 11 species are endemic. The genusCladodiopsisis no longer an endemic Madagascar genus as it also occurs in the Comoros. The phylogenetic position ofMadagopsinagen. n. is discussed based on molecular data. The intra- and intergeneric phylogeny of both new genera is discussed based on morphology and geometric morphometrics analyses of wing shape. Data are presented on sexual dimorphism with respect to eye span in the genera. The resulting allometric lines (eye span/body length) are also included in the phylogenetic analysis. The allometric lines for the closely relatedM. parvapollinasp. n., and the much largerM. apolloare compared and discussed. Allometric slopes and intercepts are identical for females of both species, while in males allometric slopes are identical, but intercepts differ considerably. An identical phenomenon was found in two closely related East AfricanDiopsisspecies with a small and a large species. Various morphological characters, including eggs, are discussed. The importance of intersternite 1–2 and synsternum 7+8 as differential characters is indicated.

A revision of the genus Teleopsis Rondani (Diptera, Diopsidae) in Sri Lanka with descriptions of two new species and a review of the other stalk-eyed flies from the island

“… Baker and Wilkinson (2001) , comparing allometric data with a phylogenetic tree based on molecular analyses, concluded that for the Diopsidae “Sexual dimorphism in eye span has evolved independently at least four times in the family ...”. Later, Feijen and Feijen (2014) and F.A.A. Feijen (pers.…”

“…For the phylogenetic position of Teleopsis within the Diopsidae can be referred to Feijen et al (2018a) . Teleopsis forms part of the Teleopsis genus group, characterised by irrorated wings.…”

“…For the rate of dimorphism D, the difference between males and females in allometric slope for eye span on body length is used in the Diopsidae ( Baker and Wilkinson 2001 ). Details on procedures for preparing genitalia slides, and procedures for taking measurements are given in Feijen et al (2018a) . For information on morphological terminology and onphotographic equipment used, the reader is referred to the same source.…”

“…This concerned three cases in the Sphyracephalinae, one in the Diasemopsis genus group, at least three in the Teleopsis genus group (the irrorated wings group) and one in the genus Diopsis. The dimorphic Malagasy Diopsis nigrosicus, distantly related to the monomorphic Diopsis ichneumonea species group of African Mainland, provided the ninth case (Feijen et al 2018b). The five Sri Lankan Teleopsis species can, based on morphological criteria, be assumed to belong to the monophyletic Teleopsis ferruginea species group.…”

A review of Madagopsina Feijen, Feijen & Feijen (Diptera, Diopsidae) with description of a new species, key to the species, and discussion of intrageneric relationships

“…This species is described herein. In Madagopsina, two species groups were distinguished by Feijen et al (2018), the Madagopsina apollo species group and the Madagopsina apographica species group. Based on morphology, allometric data and geometric morphometrics analysis of wing shape, the new species is placed in the M. apollo species group.…”