Palaeugoa ngoko 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 : 75-76

Palaeugoa ngoko Volynkin & László , sp. nov.

( Figs 25, 50)

Type material. Holotype ( Figs 25, 50): male, [ CAMEROON] “1494, Bitje , Ja River, Cameroons, 2000 ft., Oct.–Nov. 1919 ” / “1915-113.” / QR- code label with a unique number “ NHMUK010918063 ”, gen. slide No.: NHMUK010315725 (prepared by Volynkin) ( NHMUK).

Diagnosis. The forewing length is 9 mm in the male holotype. Palaeugoa ngoko is reminiscent externally of P. peregrina , but differs by its smaller size and less intense brownish suffusion on the forewing. The male genital capsule of P. ngoko differs from that of P. peregrina by the conspicuously smaller spines on the ventral part of the anellus, the somewhat narrower valva with gently arcuate costal margin (which is strongly angled medially in P. peregrina ), the broader cucullus, the much shorter, broadly triangular medial process of sacculus lacking setae (which is longer and broader, slightly curved, finger-like and densely setose in P. peregrina ) and the conspicuously narrower and longer distal saccular process. In comparison with those characters of P. aristophanousi , the genital capsule of P. ngoko has smaller spines on the ventral surface of the anellus, slightly more elongate valva with somewhat less arched costal margin, broader cucullus lacking setae ventrally, basally broader but much shorter medial saccular process and somewhat broader and longer distal saccular process. The aedeagus of P. ngoko is most similar to that of P. aristophanousi , but in P. ngoko the ventral distal crest is absent, and the dorsal distal crest is conspicuously broader and longer. The vesica of the new species differs markedly from that of both related species by the ventral diverticulum bearing a cluster of three long and robust cornuti (whereas in P. peregrina and P. aristophanousi the ventral diverticulum is armed with a cluster of numerous short and fine spinules), in addition, the presence of a cluster of seven, long and robust cornuti which character is absent in P. peregrina and P. aristophanousi . Further differences between the vesica configuration of P. ngoko and P. aristophanousi are the larger and heavily scobinated subbasal ventral diverticulum (which is smaller and granulated in P. aristophanousi ), the membranous dorsal diverticulum (heavily scobinated and granulated in P. aristophanousi ) and the smaller and less intensely granulated distal diverticulum of the new species.

Distribution. The new species is known by its single holotype collected in the historic locality of Bitje in South Cameroon.

Etymology. Ngoko is another name of the Dja River. The new species was presumably collected near the shores of the river.