Dianfosseya leakeyi, 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 : 573-575

Dianfosseya leakeyi sp. nov.

Figures 1–5

Material examined. Holotype male, Belgian Congo (today Democratic Republic of the Congo), Uele-Paulis (today Isiro in Haut-Uele District, Province Orientale) 03.April.1957, leg. Dr. M. Fontaine, genitalia slide number 27/ 102013 I. Lehmann ( RMCA).

Diagnosis. This species represents the narrowest forewings with an acute apex but a rounded termen among the Metarbelidae . The labial palpi are very short, only two-segmented. The species of Dianfosseya shares the character of very short male antennae with some species of Ortharbela Aurivillius 1910 . The hindwing venation of the holotype is remarkable in regard to vein 1A+2A because it is only obsolete towards the termen but the base is present and clearly forked. A clearly visible basal fork of 1A+2A on the hindwing occurs rarely in other metarbelid genera, namely in few undescribed species of Teragra Walker (1855) , Paralebedella Strand (1923) and in one undescribed genus (Lehmann in prep.). The wing pattern and genitalia have peculiar characters that were already described above (see description of the genus Dianfosseya ).

Description. Length of forewing in male 16.5 mm (wingspan 37.0 mm), female unknown; antenna-wing ratio 0.25:1. Head: Light brown with dark brown scales in the central part; eyes pure black; antennae very short, same colour as head; branches of antennae 3× width of shaft; antennal tips not spoon-like and with one minute thorn-like scale, bending towards apex; labial palpi brown. Thorax: Patagia largely dark brown but pale brown at base, tegulae with a triangular-shaped patch of light brown scales and a glint shine, centre of thorax dark brown, a small crest of light brown on metathorax. Hindfemora, -tibiae and -tarsi with pale brown as well as cinnamon-brown hair-like scales with a glint shine, with two pairs of tibial spurs, of which anterior spur is longer (1.2 mm). Forewing light brown, not glossy, with a broad terminal band as well as five oblique broad bands from near costa to CuA2, all six bands cinnamon-brown, CuA2 with up to five pure white and rounded spots, the largest spot close to base of CuA2; ciliae very short, 0.5 mm, brown, glossy. Underside of forewing rough-scaled at base, pale olive, glossy. Hindwing upperside olive, glossy; underside as in forewing. Wing venation see Figure 2 . Abdomen: Mainly dark brown with a short abdominal tuft.

Male genitalia. Uncus shaped like a triangle with a broad base and a bifurcated tip (ventral view). The valva lobe is broadly squarish with an arc-shaped costal margin and with an extending tip of the sacculus distal-ventrally. This extended tip is covered with many tiny setae dorsally and looks like fur, it appears to be folded, and hence, the dorsal side is easily visible in ventral view. The whole median sector of the valva has a narrow, horizontal and continuous band densely covered with short and a few long setae from the central base of valva to the centralproximal and distal-proximal parts of valva. This band of setae is bent near the central base of the valva towards the costa and appears to separate the valva lobe. The costa and sacculus with short and long setae, ventral margin of valva with long setae; vinculum and tegumen fused, forming a firm and broad ring with a rod-like structure in its upper half (ventral view); the vinculum represents one of the broadest among the Metarbelidae . This vinculum has a broad triangular shape with a rounded tip (ventral view). Saccus long, finger-shaped, broadly rounded caudally. Phallus long, slightly longer than width of valva, straight, almost of equal width, broadly rounded anteriorly but acuminate distally.

The peculiar characters were already described (see description of the genus Dianfosseya ).

Habitat. Isiro (02°46’N, 27°36’E, altitude 750 m, average annual rainfall 1530–1600 mm) is located ca. 50 km north of the large Ituri Forest (Haut-Uele District) and at the lowland rain forest-savanna boundary. The area belongs to the “Guineo-Congolian regional centre of endemism” sensu White (1983). Isiro is part of the “East Central region” sensu Grubb (1982). The latter is a Pleistocene forest refuge area including a high diversity of lowland as well as montane species in flora and fauna. Isiro is largely surrounded by various types of lowland rain forest comprising also woody legumes including, e.g. Brachystegia laurentii (De Wild.) Louis, Julbernardia seretii (De Wild.) Troupin and Dialium corbisieri Staner. The tree Ricinodendron heudelotii (Baill.) Pierre occurs particularly on abandoned farmland.

Distribution. D. leakeyi sp. nov. is known only from near Isiro, north-eastern DRC.

Etymology. The species is named after the paleoanthropologist Louis Seymour Bazett Leakey (born on the 7th August, 1903, at Kabete Mission, Kenya, died on the 1st of October, 1972, in London) to honour his life work in presenting detailed early human culture sequences resulting finally in a conception of human origins in East Africa based on his long-term field studies on the type series of stone tools and skeletal remains of early human ancestors, beginning with his first archaeological expedition in Kenya in 1926. Louis Leakey inspired Dian Fossey to undertake a study on the mountain gorillas during her first visit to Olduvai Gorge ( Tanzania) in 1963. Three years later Dian Fossey returned to East Africa. By then, Louis Leakey was one of the key persons who helped in the coordination and funding of her work on the mountain gorillas in the Democratic Republic of the Congo and later in Rwanda.

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.