Shimbania pwaniensis, Lehmann & Dalsgaard, 2023

Lehmann, Ingo & Dalsgaard, Thure, 2023, Revision of Saalmulleria Mabille, 1891 (Lepidoptera, Metarbelidae) from Madagascar with the description of three new genera and fifteen new species, Evolutionary Systematics 7 (1), pp. 133-182 : 133

Shimbania pwaniensis sp. nov.

Figs 2a , 8d

Material examined.

Holotype male, Tanzania, Pwani Region, route [road] Dar [es-Salaam] - Chalinze , “près passage voie ferré” ["near the railway crossing" / crossing ca. 2 km from the Ruvu River?], “savane” [savannah with a patch of riverine forest nearby?], 40 m, 01 May 2005, Ph. Darge [leg.], genitalia slide number 28/022009 I. Lehmann (MWM).

Description.

Head: dark chestnut, short scales, glossy; eyes dark vinaceous and surrounded by long hair-like scales of dark chestnut; a pair of pits are present on lower fronto-clypeus; pits behind labial palpi absent; antenna 0.29 length of forewing, bipectinate, branches 3.5 × width of shaft, not scaled, not widely separated at base; shaft densely covered with cream scales dorsally; labial palpi mummy brown.

Thorax: Patagia deep olive, forming a collar ring, scales with light grey tips; tegulae with long hair-like dark chestnut and black scales with a light vinaceous glint. Metathorax with crest of olive scales. Hind legs dark olive-cream with fine hair-like scales with light grey tips, on lower part of tarsus dark chestnut and black dorsally; two pairs of long tibial spurs of unequal width and length, upper pair narrow ca. 1.0 mm and 1.3 mm, lower pair of spurs broader ca. 1.2 mm and 1.4 mm long. Forewing length is 24.0 mm and wingspan 53.5 mm. Forewing upperside brownish-olive on inner half and cream-buff on outer half with a light golden glint, particularly below lower median to dorsum; below first 2/3 of 1A+2A a large dark chestnut patch mixed with black; forewing with many narrow brownish-olive lines from costa to dorsum, all veins also narrowly brownish-olive; a large and well visible brownish-olive subterminal patch, almost oval-shaped, from R2 to near middle and to near end of CuA1; termen with only few weak brownish-olive lunules; cilia short, 1.2 mm, olive with grey tips. Underside of forewing cream-buff with weak brownish-olive lines and patches with a golden glint. Hindwing upperside cream-buff with a light golden glint and with weak brownish-olive lines; cilia as in forewing; underside as in forewing.

Abdomen: Mainly olive mixed with cream-buff, glossy; abdominal tuft light olive and cream-buff, medium long, 1/4 length of abdomen. Genitalia with long uncus, 70% of length of whole gnathos, narrow, graben-like surface ventrally absent. Gnathos has gnathos arms that are large, one arm 40% the size of valva; upper part of the gnathos arm is a short band as long as 40% of basal width of valva, the lower part of the gnathal arm is large, and it does not touch the other arm but is well separated (ventral view), of broad triangular shape with a pronounced thorn-like structure and with its base 50% of the basal width of valva, without any smaller thorns as well as without a serrate dorsal edge; the gnathal arms are connected ventrally by a narrow sclerotized band that is as broad as 30% of the transtilla and is widely bifurcated in the middle. The Gnathos arms end well above the dorsal edge of the transtilla. The valva is elongated with a dorsal edge of 2.0 × the length of uncus, rectangular, ventral edge of valva S-shaped with a tip that is slightly pointed (instead of broadly rounded); sacculus not pronounced, narrow, sclerotized, 40% of length of ventral edge of valva; juxta well developed, with two broadly oval-shaped lobes and a narrowly V-shaped emargination in between, 50% the length of juxta, tips of lobes rounded. Phallus broken at middle.

Female. Unknown.

Diagnosis.

Shimbania pwaniensis sp. nov. can be separated from all other congeners by the wavy shape of the vinculum, including the ventral part, and the large gnathal arms of triangular shape with only one thorn-like appendice in front of an entirely straight dorsal edge. Furthermore, the valva has an S-shaped ventral margin with a pointed tip distally (cf. diagnosis of S. tanaensis sp. nov. above).

Distribution.

Shimbania pwaniensis sp. nov. is known from the "Usaramo floristic area" sensu Hawthorne (1984) that represents a "Southern element" within the coastal forests of East Africa and belongs to the Zanzibar-Inhambane regional mosaic. The new species was probably collected near the railway crossing (6°40'55"S, 38°40'20"E at an altitude of 37 m) and close to the Ruvu River with riverine forest patches nearby, ca. 66 km west of Dar es-Salaam. Based on its distribution, S. pwaniensis sp. nov. can be classified as a lowland species that is endemic to the coastal forests, probably also to the riverine forests, in the Usaramo floristic area; it might be widely distributed in such habitats in the Pwani Region.

Etymology.

Shimbania pwaniensis is named after the administrative Pwani Region (Tanzania) with its distinct but little known coastal forests as well as riverine forest patches, e.g. north of the Mbala-Kwalaza road, Pugu Forest Reserve, Kisiju Forest and Mkuranga Forest, located to the West, Southwest and South of Dar es-Salaam. The word “pwani” is KiSwahili and means “coast”.

The gender of the new species name is feminine.

Figures

Figure 2. a. Shimbania pwaniensis sp. nov., holotype, male, Tanzania, Pwani Region, road from Dar es-Salaam to Chalinze, near the railway crossing, ca. 2 km from Ruvu River; b. S. puguensis sp. nov., holotype, male, Tanzania, Pwani Region, Pugu Forest; c. S. kaguruensis sp. nov., holotype, male, Tanzania, Morogoro Region, Kaguru Mountains; d. S. mbarikaensis sp. nov., holotype, male, Tanzania, Morogoro Region, Mbarika Mountains, south of Mahenge Forest; e. S. kerstinhempae sp. nov., holotype, female, Tanzania, Arusha Region, Usa River, Danish Volunteer Training Centre.

Figure 8. Male and female genitalia in a pressed condition below glass: a. Shimbania baginerichardi sp. nov., holotype, male, Kenya, Kwale County, Shimba Hills National Reserve; b. S. tanaensis sp. nov., paratype, male, Kenya, Mombasa County, Shimo la Tewa; c. S. budaensis sp. nov., holotype, male, Kenya, Kwale County, Buda Forest Reserve; d. S. pwaniensis sp. nov., holotype, male, Tanzania, Pwani Region, road from Dar es-Salaam to Chalinze, near the railway-crossing, ca. 2 km from the Ruvu River.