Cosmetra Diakonoff, 1977

Aarvik, Leif, 2016, Redefinition and revision of African Cosmetra Diakonoff, 1977 (Lepidoptera: Tortricidae) with description of six new species, Zootaxa 4088 (2), pp. 245-256 : 245-246

Genus Cosmetra Diakonoff, 1977

Cosmetra Diakonoff, 1977: 103 . Type species: Cosmetra anthophaga Diakonoff, 1977: 105 .

Diagnosis. Species of Cosmetra are small to medium sized, wingspan 11–16 mm, with a simple forewing pattern typical of numerous species in Eucosmini . The forewing veins are separate; from 1/3 from cell to termen veins CuA1, A1, M3, M2, M1, and R5 run parallel. A male costal fold is absent. In the hindwing, M3 and CuA1 are stalked, and the base of M2 is curved towards the stalk of M3 and CuA1. The male genitalia are typically eucosmine with the basal two thirds of the valva gradually narrowing towards the neck and a well demarcated cucullus. The socii are strongly sclerotized, in some cases with rod-like extension. The uncus is thorn-shaped, or bifurcate distally, and in some species it is enlarged basally forming a trunk or complex dentate structure. The gnathos arms are weakly sclerotized and separate. The phallus is short and broad with 21–37 deciduous cornuti. The female genitalia are characterized by a short, broad ductus bursae that is nearly entirely sclerotized; a small membranous section is present close to the corpus bursae. The ductus seminalis inserts into the ductus bursae close to the ostium. The corpus bursae has numerous small denticles and two thorn-shaped cornuti with broad bases. The lamella postvaginalis is extended posteriorly in the middle and forms a roof over the ostium. The 7th sternite has a pair of dents, one on each side of ductus bursae close to the ostium. The female genitalia are very consistent among all the species of the genus. This is contrary to the male genitalia which in the appendages of the tegumen display a wide spectrum of structures. The uniform female genitalia convincingly hold the members of Cosmetra together as a single genus.

Systematic position. The hindwing venation with M2 at its base curved towards the stalk of M3 and CuA1, has been considered a trait defining the tribe Eucosmini (Horak 2006) . This character is not absolute, but the male and female genitalia also indicate a position within Eucosmini . A number of African tortricids have been placed in Cosmetra (Razowski & Krüger 2007, Razowski & Brown 2009, 2012, Razowski & Trematerra 2012, Razowski & Wojtusiak 2012, Razowski 2015) because they share modified and strongly sclerotized socii in the male genitalia. Males in this latter group have a pair of hair pencils at the base of the abdomen and scale tufts on the hind tibia. The female has a long ductus bursae, the greater part of which is membranous. This group is not closely related to Cosmetra , and its species will be transferred to Megaherpystis Diakonoff, 1969 in a later paper.

Diakonoff (1992) described Cosmetra rhytmosema Diakonoff, 1992 from Madagascar. This species lacks an uncus in the male genitalia. Without knowledge of the female, it is difficult to confirm the generic position given by its author. Externally, the Australian Melanodaedala scopulosana (Meyrick, 1881) , figured by Horak (2006: 319), and M. melanoneura (Meyrick, 1912) from India, figured by Clarke (1958: 373), look similar to the male of Cosmetra spiculifera (Meyrick, 1913) in forewing pattern and in the black scaling of the hindwing and the forewing underside. Both Melanodaedala Horak, 2006 and Cosmetra have strongly sclerotized socii, but Cosmetra lacks the modifications of the gnathos present in Melanodaedala , and it has a short and broad phallus. In the female genitalia the two genera share a short and broad ductus bursae with the inception of ductus seminalis near the ostium. In the corpus bursae both have numerous denticles except in an area near the signa. The latter trait is present in C. spiculifera and in C. larseni , sp. n. ( Figs. 19, 20 ). It is interesting that Horak (2006) noted that “the South African Eucosma tumulata could well be congeneric [with Melanodaedala ] but needs further study.” For the time being Cosmetra is placed close to Melanodaedala in Eucosmini .

The type species of Cosmetra . Diakonoff (1977) proposed the genus Cosmetra with C. anthophaga Diakonff, 1977 as the type species. Cosmetra anthophaga is only known from the type series collected on Réunion. Diakonoff (1977) figured the genitalia of both sexes. Guillermet (2011) figured the genitalia and a colour image of the adult. Cosmetra anthophaga is very similar to C. spiculifera (Meyrick, 1913) both externally and in the genitalia. It is possible that C. anthophaga and C. spiculifera are synonyms.

Figures

FIGURES 19 – 22. Female genitalia of Cosmetra. 19. C. spiculifera (Meyrick) (slide LAA 2015.008). 20. C. larseni, n. sp. (slide NHMO 2162). 21. C. tumulata (Meyrick) (slide NHMO 2717). 22. C. truncana, n. sp. (slide L. Aarvik 2014.014). Scale 1 mm.