Mormogystia brandstetteri Saldaitis, Ivinskis & Yakovlev

Borth, Robert, Ivinskis, Povilas, Saldaitis, Aidas & Yakovlev, Roman, 2011, Cossidae of the Socotra Archipelago (Yemen), ZooKeys 122, pp. 45-69 : 46-47

Mormogystia brandstetteri Saldaitis, Ivinskis & Yakovlev sp. n. Figs 1, 22127

Type material.

Holotype ♂ (Fig. 1), central part of Socotra Island, Diksam loc., 14 January 2010, leg. A. Saldaitis (deposited in MWM/ZSM; slide No. BJ 1524). Paratypes: 77 ♂ and ♀ (Fig. 2), with same labels as holotype; Socotra Archipelago, Samha Island W., N 12°09', E 052°59', 23-24 February 2008, leg. A. Saldaitis; Socotra Archipelago, Abd al Kuri Island, Towanie vill. env., N 12°10', E 052°13', 25-27 February 2008, leg. A. Saldaitis; Socotra Island, Di Hamri loc., 1 March 2008, leg. Saldaitis; Socotra Island, Di Hamri loc., 20-21 November 2008, leg. Saldaitiene & Saldaitis; Socotra Island, hills near Hadibu, 21 March 2009, leg. A. Saldaitis; Socotra Island, Diksam canyon, 23 March 2009, leg. A. Saldaitis; W Socotra, Shuab, coast line, mangroves, 24 March 2009, leg. A. Saldaitis; N Socotra Island, Ayhft valley, 22 November 2008, leg. A. Saldaitis; S Socotra Island, Wadi Difarroha South side, 15 January 2010, leg. A. Saldaitis; N Socotra Island, Ayhft valley, 12 January 2010, leg. A. Saldaitis; N Socotra Island, Wadi Kam, 13 January 2010, leg. A. Saldaitis; N Socotra Island, top of Ayhft valley, 17 January 2010, leg. A. Saldaitis; E Socotra Island, sand dunes near Irisseyl loc., 18 January 2010, leg. A. Saldaitis; NE Socotra Island, Wadi Difarroha, North side, 19 January 2010, leg. A. Saldaitis (coll. ASV; JBW; LLE; MWM/ZSM; NRCV; RYB). Slide No. BJ 1532 (female).

Diagnosis.

The new species differs from the related species Mormogystia reibellii ( Oberthür, 1876) (Fig. 5), Mormogystia proleuca (Hampson in Walsingham et Hampson, 1896) (Figs 3, 4) and Mormogystia equatorialis (Le Cerf 1933) (Fig. 6) in external appearance, genitalia, DNA and distribution. The new species has a larger wingspan than its congeners: Mormogystia brandstetteri sp. n. 33-35 mm, Mormogystia reibellii 27-31 mm, Mormogystia proleuca 25-29 mm, Mormogystia equatorialis 26 mm. All species of the genus Mormogystia have a similar forewing pattern, but the ground colour of the new species is black as opposed to light ochre, light brown and brown, respectively, for Mormogystia reibellii , Mormogystia proleuca and Mormogystia equatorialis . The head, thorax and abdomen of Mormogystia brandstetteri are intense grey compared to light yellow in Mormogystia reibellii andlight yellow and white in Mormogystia proleuca and Mormogystia equatorialis . Unlike the other species Mormogystia brandstetteri has a black costal spot on the ventral hindwing; in Mormogystia reibellii (Figs 23, 24)and Mormogystia proleuca (Fig. 22) uncus apically tapering, strongly sclerotised valvae not widening and not forming a straight angle; in Mormogystia brandstetteri uncus broad, apex of valvae form a straight angle; in Mormogystia reibellii and Mormogystia proleuca saccus rounded, apically without denticle, whereas in the new species saccus pointed, apically with a denticle; Mormogystia proleuca aedeagus at the basal end markedly narrowing, gradually widening towards apex; Mormogystia reibellii aedeagus of the same width from its middle to apex; in Mormogystia brandstetteri aedeagus widening at proximal end, gradually tapering towards apex. In the most closely related species, Mormogystia proleuca , the bursa is apically broader than basally (Fig. 28) unlike in the new species where the corpus bursae is significantly broader.

Distribution.

Mormogystia brandstetteri is endemic to the Socotra Archipelago while Mormogystia reibellii is distributed in North Africa and the northern part of the Arabian peninsula, Mormogystia proleuca is found in the southern part of the peninsula, and Mormogystia equatorialis is widespread in Kenya. Hampson (1903) and Rebel (1907) believed Mormogystia proleuca to be endemic to the Socotra Archipelago and later Hacker (1999) reported Mormogystia reibellii from Socotra, but the new species described herein was probably implied.

Molecular Analysis.

While molecular results alone are insufficient to definitively separate Mormogystia brandstetteri from Mormogystia proleuca , they help corroborate the morphological evidence. Evolutionary distances using the Kimura two-parameter model for comparing four specimens of Mormogystia brandstetteri to four Mormogystia proleuca and to three Mormogystia reibellii specimens, was at least 1.55% and 5.65%, respectively.

Description.

Male: Forewing costal margin length of holotype 15 mm, wingspan 33 mm; mean forewing length of paratypes 16 mm, wingspan 35 mm; head, thorax, abdomen and tegulae grey; antennae bipectinate, ½ the length of forewing; ground colour of forewing black, with white silvery pattern. Three white silvery patches form the pattern: fascia of even width runs along the entire costal margin, median fascia widening medially reaches the outer margin of forewing; lower silver patch originates at basal edge and extends along dorsal wing margin to middle. This patch enclosed by ground colour; adterminal line white; fringe grey. Dorsal surface of forewing greyish-white; costal, outer and dorsal margins greyish-black. Hindwing uniform, white, with greyish black spot at costal margin. Female (Fig. 2): Forewing length of allotype 23 mm, wingspan 48 mm; antennae filiform; wing pattern as in males. Intraspecific variation. Adterminal line in some specimens missing; contours of silvery spots forming the pattern vary; hindwings grey.

Male genitalia (Fig. 21). Uncus broad, slightly narrower than its length; apex wide, slightly rounded; arms of gnathos long and strong; gnathos very broad, with rounded apex; apex of saccus gradually tapering, with a pointed denticle; valvae symmetrical, with straight margins, gradually widening apically; costal margin with strong and wide sclerotisation; apex flat; arms of transtilla medium sized, strong, denticle-shaped; juxta large, strongly sclerotised, belt-shaped with a small indentation apically and a conspicuous boat-shaped margin at the basal area; aedeagus strong, straight, large, widening at the proximal end; vesica simple, wide, without cornuti.

Female genitalia (Fig. 28). Papilla analis narrow, covered with short, thin setae; apophysis posterioris 1.4 times longer than apophysis anterioris; antevaginal plate belt-shaped, pointed at the ends; ductus bursae sclerotised; corpus bursae shaped like a long narrow sac, not sclerotised; signa absent.

Bionomics and distribution.

Both males and females of the new species were strongly attracted to light and were distributed in almost all habitats of Socotra Island as well as the smaller islands of the archipelago - Samha and Abd al Kuri. Acacia is a likely food plant for Mormogystia brandstetteri as larvae of the closely allied species Mormogystia proleuca feed on Acacia [Hampson, 1896]. Also, the new species is especially abundant in the central part of the island, in deeper canyons or rich oasis-like valleys where f orests haven’t been cut for fuel like elsewhere on the island. Diksam canyon (Fig. 30), a prime locality for Mormogystia brandstetteri , contains the following plants: Acacia pennivenia , Jatropha unicostata , Lycium socotranum , Gnidia socotrana , Buxus hildebrandtii , Croton socotranus , Leucas virgata , Cissus hamaderohensis , Punica protopunica , Ficus vasta , Euphorbia socotrana , Jathropha unicostata , Lycium socotranum , Gnidia socotrana , Buxus hildebrandtii , Trichocalyx sp., Mitolepis intricata , Ballochia spp., Aloe perryi , Adenium obesum , Asparagus africanus , Seddera fastigiata , Aerva lanata , Rhinacanthus scoparius , Levandula nimmoi , Ocimum forskahlei , Cissus hamaderohensis ( Miller and Cope 1996). Mormogystia brandstetteri flies with several other Socotra Archipelago endemic moths such as Meharia yakovlevi Saldaitis & Ivinskis, 2010, Aethalopteryx diksami Yakovlev & Saldaitis, 2010, ( Cossidae ), Pelosia sokotrensis (Hampson, 1900), Siccia butvilai Saldaitis & Ivinskis, 2008, ( Arctiidae ), Cerocala socotrensis Hampson, 1899, Agrotis brachypecten Hampson, 1899, Leucania diopsis Hampson, 1905 and Mythimna sokotrensis Hreblay, 1996 ( Noctuidae ).

Etymology.

The new species is dedicated to our good friend Johann Brandstetter, an eminent German painter and entomologist.