Palaeugoa megala Volynkin & László, 2020

Volynkin, Anton V. & László, Gyula M., 2020, Revision of the genus Palaeugoa Durante, 2012, with descriptions of seven new species (Lepidoptera: Erebidae: Arctiinae: Lithosiini), Ecologica Montenegrina 36, pp. 53-77 : 63-68

Palaeugoa megala Volynkin & László , sp. nov.

( Figs 15, 16, 41, 42)

Type material. Holotype ( Figs 15, 41): male, “ Rwanda, Nyungwe, 12.X.[19]74, B. Turlin [leg.], 2000m ”, gen. slide No.: ZSM Arct. 2019-217 (prepared by Volynkin) ( ZSM).

Paratypes. RWANDA: 1 male, Nyungwe , 2000m, 23.IV.[19]77, B. Turlin [leg.], gen. slide No.: ZSM Arct. 183/2017 (prepared by Volynkin) ( ZSM) ; 1 male, Nyungwe NP, 2000m, Kamiranzowu Swamp , 2°29’S, 29°08’E, 6.VIII.2008, leg. J. & W. De Prins, De Prins Coll. BMNH (E) 2014-125, gen. slide No.: NHMUK010315267 (prepared by Volynkin) ( NHMUK).

Diagnosis. The forewing length of the new species is 11.5–12 mm in males. Palaeugoa megala can easily be distinguished from all other species of the P. spurrelli species-group by its considerably larger size. The male genital capsule of the new species is most similar to that of P. smithi due to the presence of a medial saccular process, but differs from it clearly by the broader uncus, the shorter, densely spinulose and detached transtillar processes (in P. smithi those are longer, fused into one smooth-surfaced plate with a deep medio-distal depression), the membranous anellus (which is weakly spinulose in P. smithi ) and the presence of a large medio-ventral process of juxta (absent in P. smithi ). In addition, the new species has somewhat wider vinculum, convex costal margin of valva (straight in P. smithi ), a well-developed costal process (absent in P. smithi ), broader cucullus compared to those of P. smithi . The medial saccular process of P. megala is considerably longer, somewhat thicker, narrower at base and erected medially, whereas that is shorter and narrower in P. smithi having a markedly broader basal section erected distally. The distal saccular process of the new species is somewhat more robust, more curved dorsally compared to that of P. smithi . The aedeagus of P. megala is conspicuously larger than that of P. smithi , it is straight, equally wide in its full length with a very short coecum, whereas that of P. smithi is slightly arched medially and gradually tapered distally, having a well-developed coecum. The vesica of P. megala is markedly broader than that of P. smithi , having two elongate, adversely projected lateral diverticula bearing robust cornuti apically, whereas that of P. smithi has a single, shorter diverticulum directed distally, bearing apical cornuti.

Female is unknown.

Distribution. The species is known from Rwanda only, the type specimens were collected in the high elevation rainforest of the Nyungwe Forest.

Etymology. ‘Megalo’ is a Latin transliteration of the Greek word ‘μεγάλο’ meaning ‘large’. The specific epithet refers to the size of the new species which is the largest in the species-group.