Achrocerides smithi, Taberer & Giusti, 2022

Taberer, Tabitha R. & Giusti, Alessandro, 2022, Revision of Achrocerides Hering, 1937 (Lepidoptera: Chrysopolomidae), Ecologica Montenegrina 59, pp. 24-37 : 34-36

Achrocerides smithi sp. n. ( Figs. 9 — 10 , 18 — 19 )

https://zoobank.org/ urn:lsid:zoobank.org:act:65FA0A34-3C66-435B-8702-9203D95BF41B

Holotype: Male, “LA MABOKE / REP. CENTRAFRIC. / V-1965 / Michel BOULARD” // “ Coll.Mus.Tervuren ” // “dét. G.Poncin / achrocerides / theorini auriv.” // “Chysopolomidae [sic] / P.Kurshakov pr. / CHRY-11-84” ( RMCA).

Paratypes: Central African Republic. 4 males, La Maboke, 24.xi.1964 — 9.v.1966, Pujol, R. leg., gen. slide No.: TT 201 ( RMCA) .

Description

Male. Forewing length 22 mm. Head, collar, tegula, and thorax tawny brown. Antenna bipectinate; antennae and palps ochreous yellow. Legs beige laterally with sparse dark scale spots, ochreous yellow medially. Abdomen uniformly brown-beige, sometimes with a few, irregular dark scales. Forewing. Broad, rounded; ground colour beige to tawny-brown, although slightly paler from post-medial line to outer margin; wing speckled sparsely with dark scales that are mostly concentrated along costal margin and near thorax. Post-medial line grey-brown, with scaling extending on the veins distally; post-medial line kinked at vein M1 near outer margin. Postmedial area with a diffuse grey-brown triangular patch between veins R3 and M1; discal spot light beige, rounded, with diffuse margin. Fringe long, slightly darker than ground colour, cilia sometimes black in distal half. Hindwing. Rounded, with undulate margin at the tornus. Ground-colour same as forewing or slightly paler beige; medial line dark grey-brown, wider than that of forewing. Sparse dark scales concentrated in distal half. Outer margin with a diffuse, pale grey-brown triangular patch between veins M1 and M2. Fringe long, slightly darker than ground colour, cilia black in distal half. Underside of wing uniformly pale beige with some irregular clusters of grey scales concentrated mostly along the costal margin of the fore- and hindwing. Forewing discal spot visible traceable. Outer margin with diffuse pale grey-brown triangular patch between veins R3 and M1 on forewing and between veins M1 and M2 on hindwing. Fringe darker than ground colour; cilia sometimes black in distal half.

Female. Unknown.

Male genitalia. Uncus elongate, triangular, strongly sclerotised apically. Tegumen narrow. Transtilla comprised of two long, narrow, apically pointed posterior processes, and two thin, short, apically pointed anterior processes. Juxta with bilobate base, with small, strongly sclerotised, rectangular process antero-medially, and with two moderately long, narrow, tapered, distally pointed lobes accompanying phallus laterally. Vinculum broad, rounded. Valve wide at base, triangular, narrowing distally with rounded point on dorso-apical edge. Phallus medially slightly curved, relatively thin, long, proximally surrounded with heavily sclerotised manica fused ventrally to caudal lobes of juxta, weakly sclerotised at the distal end with apical split. Vesica extremely short, membranous.

Diagnosis. Externally, the new species is similar in size to A. theorini whilst also displaying the typical slight variability in wing colouration and so the two cannot be readily distinguished. However, in the male genitalia, the diagnostic characters are clear. In A. smithi , the valva is triangular in shape whilst in A. theorini the valva is distally truncate, almost rectangular in some specimens. In addition, the lobes of the juxta are markedly shorter and slightly wider in the new species than in A. theorini , which has longer and narrower juxta processes. When comparing the new species with A. flavoantennata , the taxa can be readily distinguished externally by the much smaller size of the new species. In addition, the two species do not occur sympatrically and the Ubangi and Sangha Rivers may be acting as a barrier for dispersal of the new species. In the male genitalia, the new species is close to A. flavoantennata in terms of the juxta processes, which are broader and shorter in both species relative to those of A. theorini . The distal portion of the valve is also much more elongate in these two species compared to the truncate valve of A. theorini , although in A. smithi the costal edge is slightly narrower and more rounded distally compared to the more triangular, pointed valve of A. flavoantennata . Finally, the membrane connecting the anterior transtilla processes of the new species is less sclerotised compared to that of its closely allied species.

Distribution ( Fig. 20 ). Achrocerides smithi is likely confined to the south-east region of the Central African Republic with a similar distribution to another Chrysopolomid species, Strigivenifera marina Kurshakov & Zolotuhin, 2013 . The Ubangi-Sangha interfluvial region is known to harbour many endemic species of insects (e.g. Hemp & Massa 2021) as well as birds (e.g. Marks 2010), and the new species is likely to be another unique species to this biodiverse region of Africa.

Etymology. This new species is dedicated to Richard Smith, founder and Chairman of the Board of Trustees of the African Natural History Research Trust, in recognition of his consistent support for the advance of research in the field of Lepidoptera and taxonomy.

Figures

Figure 20. Distribution of Achrocerides species (TL = Type locality).

Figures 1—10. Adults. Figs. 1—5: Achrocerides theorini. 1: ST, Male, Gaboon [Gabon] (SMNH); 2. Male, Angola, Quicolungo (gen. slide No. NHMUK 010317727) (NHMUK); 3. Male, Sierra Leone, Kono Province (ANHRT); 4. Male, Uganda, Kibale Forest (gen. slide No. 31.061) (MWW); 5. Female, Liberia, Nimba Mountains (gen. slide No. LG 5794) (ANHRT). Figs. 6—8: Achrocerides flavoantennata comb. n., 6: HT, male, DRC, (GU 2010-02) (MCG); 7. Male, DRC, Kabunga (gen. slide No. TT 132) (ANHRT); 8. Male, DRC, Maniema (gen. slide No. CHRY-11-80) (RMCA). Figs. 9—10: Achrocerides smithi sp. n., 9: HT, male, Central African Republic, La Maboke (gen. slide No. CHRY-11- 84) (RMCA); 10: Male, Central African Republic, La Maboke (gen. slide No. TT 201) (RMCA).

Figures 16-19. Genitalia (a: clasping apparatus, b: phallus). Figs. 16—17: Achrocerides flavoantennata comb. n., 16: Male, DRC, Kabunga (gen. slide No. TT 132) (ANHRT); 17: Male, DRC, Moutombe [=Mondombe] (gen. slide No. TT 198) (RMCA). Figs. 18—19: Achrocerides smithi sp. n., 18. HT, Male, Central African Republic, La Maboke (gen. slide No. CHRY-11-84) (RMCA); 19: Male, Central African Republic, La Maboke (gen. slide No. TT 201) (RMCA).