Acronicta (Viminia) kissi, Volynkin & Saldaitis, 2021

Volynkin, Anton V. & Saldaitis, Aidas, 2021, On the taxonomy of the genus Acronicta Ochsenheimer (Lepidoptera, Noctuidae) V. A new species of the subgenus Viminia Chapman from Vietnam (Lepidoptera Noctuidae: Acronictinae), Zootaxa 5039 (1), pp. 134-138 : 134-138

Acronicta (Viminia) kissi sp. n.

( Figs 1, 2 , 9, 10 )

Type material. Holotype ( Figs 1 , 9 ): male, “ 10–25.V.2013, South Vietnam, Lâm Đồng Province, Lạc Dýõng District , Tây Nguyên Highlands, Bidoup Núi Bà NP, local collector leg.”, gen. prep. No.: AV3096 (prepared by Volynkin) ( ZSM, ex CAV).

Paratypes: 2 males with the same data as in the holotype, gen. prep. No.: AV3095 (prepared by Volynkin) ( CAV) .

Diagnosis. The new species ( Figs 1, 2 ) differs from A. digna ( Figs 3–5 ) in the indistinct antemedial line, the indistinct grey and less dentate postmedial line (it is whitish with a more dentate black outer margin in A. digna ), and the paler hindwing with a narrower terminal band and a more indistinct discal spot. Additionally, the medial sub-posterior dash of A. kissi sp. n. is paler and more diffuse than in A. digna and the reniform stigma is paler and has more diffuse edges. Compared to A. metaxantha ( Fig. 6 ), the new species has pale grey body and forewing colouration (dark grey in A. metaxantha ), a more indistinct forewing pattern and a pale greyish creamy hindwing (yellow in A. metaxantha ) wing a markedly narrower terminal band. The new species is also externally reminiscent to A. (Viminia) grumi grumi ( Fig. 7 ) and A. (Viminia) indica ( Fig. 8 ) but can easily be distinguished by the grey forewing with an indistinct pattern (whereas the forewing ground colour of A. grumi grumi and A. indica is brownish grey and the pattern is more distinct) and the presence of a dark grey terminal band on the hindwing. The genitalia of A. kissi sp. n. ( Figs 9, 10 ) are dissimilar to those of A. grumi grumi ( Fig. 15 ) and A. indica ( Fig. 16 ) in a number of features of the genital capsule and vesica structures. The male genital capsule of the new species ( Figs 9, 10 ) is very similar to those of A. digna ( Figs 11–13 ) and A. metaxantha ( Fig. 14 ) but differs in the somewhat shorter valva (the valva to tegumen-vinculum complex lengths ratio is 1:1.11 vs. 1: 1.22 in A. digna and 1: 20 in A. metaxantha ) and the somewhat more prominent peniculus. Additionally, the valva apex of the new species is somewhat narrower than in A. digna . The aedeagus of A. kissi sp. n. lacks a subapical ventral protrusion which is present in A. digna and A. metaxantha and differs from that of A. digna in its narrower proximal section. Compared to A. metaxantha , the aedeagus of A. kissi sp. n. is also somewhat more dilated distally and less curved medially. The vesica of the new species differs from those of A. digna and A. metaxantha in the broader lobes of the subbasal dorsal diverticulum located on the same level distally (whereas in A. digna one of the lobes is located more proximally) and the somewhat shorter main chamber bearing more numerous cornuti (11–12 vs. 5–9 in A. digna and 8–9 in A. metaxantha ). Additionally, in A. kissi sp. n., the distal cornuti in the row are equal in length to the proximal ones whereas two or three distal cornuti of A. metaxantha are conspicuously longer and thicker than the proximal ones.

Description. External morphology of adults ( Figs 1, 2 ). Forewing length 19–20 mm in males. Male antenna filiform. Head and thorax dark grey with admixture of whitish scales. Forewing ground colour grey. Basal dash black. Antemedial line double, sinuous, with indistinct blackish-grey margins. Medial sub-posterior dash dark grey, diffuse. Ordicular stigma small, rounded, pale grey, with thin blackish margin diffuse anteriorly. Reniform stigma pale grey with dark grey suffusion medially and blackish-grey diffuse margins. Costa with blackish suffusion at reniform stigma. Postmedial line pale dentate on veins, grey with diffuse dark grey outer and inner margins, curved medially. Postmedial and subterminal area with diffuse blackish-grey spots medially and sub-posteriorly. Subterminal line indistinct, irregularly dentate, pale grey inwardly and dark grey outwardly. Terminal line interrupted into blackish dots between veins. Cilia grey with blackish dots fused with dots on terminal line. Hindwing pale greyish creamy with slight grey suffusion on veins and brownish-grey terminal band indistinct at anal margin. Cilia brownish-grey. Male genitalia ( Figs 9, 10 ). Uncus elongate, slender, laterally flattened, down curved and apically pointed. Tegumen short and broad, penicular lobes short and rounded. Vinculum longer than tegumen, with short but well-sclerotized V-shaped saccus. Valva elongate and smoothly tapered distally with slightly dilated and rounded apex. Saccus short and broad, with convex dorsal margin. Clasper short and narrow. Harpe elongate and slender, apically pointed with distal half curved outwards. Juxta elongate shield-like, dilated apically, with short medial protrusion ventrally. Aedeagus relatively broad (length to width ratio 1:3.3), with short coecum (ca. 1/5 of aedeagus length), somewhat dilated distally. Vesica with ventral subbasal sclerotized stringlike plate directed distally and reaching the base of vesica ejaculatorius. Subbasal dorsal diverticulum elongate and bilobate distally. Main chamber protrudes distally, with wide, weakly sclerotized and rugose area bearing a short sclerotized and serrate globular diverticulum laterally and dorsal row of 11–12 tiny needle-like cornuti on weakly sclerotized conical bases. Vesica ejaculatorius broad (ca. half of aedeagus width), projecting ventrad.

Female unknown.

Distribution. The new species is known only from the Central Highlands of Vietnam (Lâm Đồng Province).

Etymology. The species is named after Dr Ádám Kiss (Gyöngyös, Hungary), a renowned expert in Acronictinae taxonomy.

Figures

FIGURES 1–8. Acronicta spp.: adults. Depositories of the specimens: 1 in ZSM (ex CAV); 2 in CAV; 3, 4 and 8 in NHMUK (©The Trustees of NHMUK); 5 in ZFMK; 6 in CGH (photo by H.-L. Han); 7 in ZISP.

FIGURES 9–12. Acronicta spp.: male genitalia. Depositories of the specimens dissected: 9 in ZSM (ex CAV); 10 in CAV; 11 and 12 in NMNS.

FIGURES 13–16. Acronicta spp.: male genitalia. Depositories of the specimens dissected: 13 in CAV; 14 in NEFU (photo by H.-L. Han); 15 and 17 in ZISP (photo by A.Yu. Matov).