Dianfosseya, Lehmann, Ingo, 2014

Lehmann, Ingo, 2014, Description of two new genera and two new species of Metarbelidae (Lepidoptera, Cossoidea) from the Northeastern Congolian Lowland Forests Ecoregion (Central Africa), Zootaxa 3895 (4), pp. 570-580 : 571-573

Dianfosseya gen. nov.

Type species: Dianfosseya leakeyi sp. nov.

Diagnosis. Dianfosseya possesses typical metarbelid characters (cf. Holloway 1986; Edwards et al. 1998; Lehmann 2012; Lehmann & Rajaei 2013) and is defined as a new genus based on putative morphological apomorphies.

It appears that the genera Dianfosseya gen. nov. and Janegoodallia gen. nov. share symplesiomorphic character states (A–C) in the male genitalia as well as on the forelegs:

A) The uncus is large and is shaped like a triangle, its tip is very shortly bifurcated, the base of the uncus is broad (ventral view). Such a broad uncus is probably a very ancient character (A. Hausmann pers. comm. 2014).

B) The valvae consist of two large lobes that are broadly squarish with an arc-shaped costal margin. Each lobe has one tip of the sacculus that extends beyond the margin of the valva. This tip appears to be folded in both genera.

C) The epiphysis is unusually long, tube-like, slightly bent and narrow extending from base of foretibiae to almost half of first tarsomere in both genera.

The occurrence of a large uncus that is shaped like a triangle, the broadly squarish valvae with an arc-shaped costal margin and the very long, tube-like and slightly bent epiphyses in Dianfosseya and Janegoodallia appear to be symplesiomorphies within the metarbelid genera. In Dianfosseya the uncus is 1.8× longer than broad while in Janegoodallia the uncus is almost as long as broad; the valvae extend to the base of the uncus in Dianfosseya while the lobes of the valvae are well below the base of the uncus in Janegoodallia ; the epiphyses are more bent in Janegoodallia , but very long, tube-like and densely covered with long scales in both genera. Another difference occurs in regard to the long and unusually narrow forewings with an acute apex but a rounded termen that is more developed in Dianfosseya . Such a forewing shape is unique among the Metarbelidae . It is similar to the shape of the forewings of the Cossidae that are longer, narrower and apically more strongly acute if compared with the Metarbelidae ; the latter have usually long but broad wings with a rounded apex ( Lehmann & Rajaei 2013). The occurrence of these differences suggests the existence of two separated lineages.

The following putative morphological apomorphies exist in Dianfosseya (A–D):

A) The male genitalia possess a prominent gnathos-like structure (probably a relict structure and once an appendage of the gnathos) that belongs neither to the valva nor to the tegumen. It is almost as large as the saccus and has one long as well as one short thorn-like process on the ventral surface at the end and in between 12–14 short teeth-like processes on the ventral surface at the top. This gnathos-like structure is unique among the Metarbelidae .

B) Another unique structure of the genitalia is a long and narrow tube-like process below of the bifurcated uncus tip and parallel to the edge of the uncus. It is twice as large as the bifurcated tip and is probably attached to the inner caudal margin of the uncus. This tube-like process has many unusually long setae.

C) The extended tip of the sacculus is covered with tiny setae dorsally, looking like fur.

D) The forewing pattern is unique with a broad terminal band as well as five broad and oblique bands, all cinnamon-brown and parallel to each other, running from close to the coastal margin to CuA2.

The combination of characters presented above justifies the erection of two new genera. The most outstanding external characters of both genera are the narrow forewing in Dianfosseya as well as the unique largely transparent wings of Janegoodallia (cf. above) in regard to the Metarbelidae even in a worldwide context. Only one Afrotropical species is currently recognized for each genus: Dianfosseya leakeyi sp. nov. and Janegoodallia davenporti sp. nov.

Description of Dianfosseya gen. nov.: Regarding all Metarbelidae , the single specimen representing this genus is of medium size (wingspan 37.0 mm). Head: Rough-scaled, without pits and without a pair of projections on lower fronto-clypeus; the labial palpi are short, only two-segmented (this is rarely found among the Metarbelidae where species usually have three-segmented labial palpi), and their length is less than the eye diameter; male antennae bipectinate, flagellum scaled dorsally; dorsal side of branches scaled; ventral side of branches with sensory setae which are three times longer than the width of branch. Thorax: Densely covered with hair-like scales; with a short crest on metathorax; epiphysis very long (1.9 mm), narrow, slightly bent and tube-like from base of foretibiae to almost half of first tarsomere. Hindlegs with two pairs of narrow tibial spurs (ca. 1.2 mm). Forewing upperside with a simple pattern of six oblique bands with few contrasting colours ( Figure 1 ). Wing venation ( Figure 2 ) similar to the genus Moyencharia Lehmann 2013 , with three differences (a–c):

a) Dianfosseya has on the forewing a vein 1A+2A that is not forked at base, instead the base is coalesced, thick and oval-shaped.

b) The discal cell of the forewing has a much larger anterior part of cell.

c) In the hindwing, Rs+M1 is much longer stalked.

In forewing CuP absent, CuA2 originating from hind margin of posterior part of cell, CuA1, M3 and M2 basally separated and initiating from posterior angle of posterior part of cell, M1 initiating from below upper end of distal vein of anterior part of cell, R1 initiating from anterior margin of anterior part of cell, R2 initiating from anterior angle of areole, R3+R4+R5 are shortly stalked and initiate from the posterior angle of areole, Sc more or less parallel to R1; stem of vein M (in between anterior part of cell and posterior part of cell) well developed. In hindwing 3A and CuP present, 1A+2A obsolete towards termen but the base is present and clearly forked (on both hindwings), CuA2 initiating from near posterior angle of posterior part of cell, CuA1, M3 and M2 basally separated, initiating from posterior angle of posterior part of cell, M1 and Rs initiating from a very long stalk of the anterior angle of anterior part of cell, with a bar from Rs to Sc+R1; stem of vein M in discal cell present; ciliae very short. Retinaculum and frenulum absent. Abdomen: With dense hair-like scales and a short abdominal tuft (not longer than 15% of the length of the abdomen).

Male genitalia: Saccus long, broadly elongated and rounded; uncus very large and triangular-shaped, bifurcated and almost acuminate at tips with a small tube-like process below, probably attached to the caudal margin of the uncus. Valva broadly squarish with an arc-shaped costal margin and with an extending tip of the sacculus distal-ventrally; unusually long setae occur on the ventral surface of uncus, on the sacculus and, mixed with shorter setae, in a band-like pattern on the central part of the inner side of valva. A prominent gnathos-like structure present. Juxta large and wide. Phallus simple and longer than genitalia length (in a lateral view), vesica without cornuti ( Figures 3–5 ).

Female. Unknown.

Distribution. Dianfosseya is found near Isiro ( DRC), which is part of the “Northeastern Congolian Lowland Forests ecoregion” (Central Africa). The species of the new genus is treated herein preliminarily as endemic to the “Northeastern Congolian Lowland Forests ecoregion” as defined by Burgess et al. (2004).

Ecology. The species of Dianfosseya appears to be associated with lowland areas comprising a mosaic of small grasslands, farmlands and forests occurring in the periphery of the large lowland rain forest block with high mean annual rainfall of at least 1500 mm. The larger forests represent “Mixed moist semi-evergreen Guineo-Congolian rain forest”, “Drier peripheral semi-evergreen rain forest” and “Single-dominant moist evergreen and semievergreen Guineo-Congolian rain forest” sensu White (1983).

Etymology. Dianfosseya is named after the primatologist Dian Fossey (born on the 16th of January, 1932, in San Francisco, U.S.A., murdered at Karisoke Research Center, Rwanda, on December 26th or 27th, 1985) to honour her love and life work for Africa and for showing the whole world her detailed long-term field studies on the mountain gorillas, beginning in December 1966, as well as her efforts to enforce anti-poaching laws by using her own funds to undertake the first anti-poaching patrols to protect the gorillas on Mount Karisimbi and Mount Visoke. Dian Fossey’s attention that concerted and active conservation measures are needed to protect the mountain gorillas and their habitats in the Virunga volcanic mountain range (Volcanoes National Park, Rwanda) helped to conserve this species. Much effort is still necessary today to protect the gorillas, one of our close relatives among the great apes.

The gender of the new genus is feminine.

Figures

FIGURES 1 – 5. Dianfosseya leakeyi sp. nov. 1, male, holotype with wing pattern; 2, Wing venation; 3, Genitalia in lateral view with the simple phallus below; 4, Genitalia in ventral view with a large gnathos-like structure, probably once an appendage of the gnathos, and the broad, triangular-shaped uncus above; 5, Enlargement of the former appendage of the gnathos.