Barsine geometroides, Volynkin, 2021

Volynkin, Anton V., 2021, Three new species of the genus Barsine Walker (Lepidoptera: Erebidae: Arctiinae) from Taiwan, Zootaxa 5032 (3), pp. 411-422 : 412-414

Barsine geometroides sp. n.

( Figs 1–3 , 18 )

Type material. Holotype ( Figs 1 , 18 ): male, “ Taiwan, Prov. Tai-Tung, 2 km E of Hsiangyang , 2200m, 11.– 13.03.1996. leg.: Gy. Fábián & L. Németh ” / “Genitalpräparat [genital slide] Heterocera Nr. 35.741 Museum Witt München” ( MWM / ZSM).

Paratypes. TAIWAN: 10 males, same data as for holotype, gen. prep.No.: MWM 35.723 (prepared by Volynkin) ( MWM / ZSM) ; 2 males, Taiwan , Prov. Kao-Hsiung, 15 km NE of Taoyuan, 1850m, 12.III.1996, Gy. Fábián & L. Németh leg., gen. prep. No.: MWM 35.742 (prepared by Volynkin) ( MWM / ZSM).

Diagnosis. The new species ( Figs 1–3 ) is externally reminiscent of B. ponlai ( Figs 4, 5 ), but can be distinguished by its slenderer body, the shorter rami of the male antenna, the somewhat wider forewing with a somewhat more smooth tornus and the presence of a diffuse medial transverse fascia on the hindwing. Additionally, the medial line of the forewing of B. geometroides sp. n. is anteriorly more curved than in B. ponlai , and the postmedial line is thinner and dentate on veins whereas it is thicker and smooth in B. ponlai . The male genital capsule of the new species ( Fig. 18 ) is dissimilar to that of B. ponlai ( Fig. 20 ) and is vaguely reminiscent of only of that of the externally dissimilar B. mactans ( Figs 9 , 19 ) due to the short (in proportion to the valva length) basal saccular process and the reduced distal costal process. However, the male genital capsule of B. geometroides sp. n. differs clearly from that of B. mactans in the markedly thicker uncus, the subdistally dilated valva, the shorter basal saccular process, the shorter lobes of the distal saccular process, and the triangular medial costal process having an anteriorly narrower base. The juxta of the new species has dilated basal lobes and tapered apical lobes whereas in B. mactans the basal lobes are tapered and curved and the apical lobes are subapically dilated. Additionally, the vinculum of B. geometroides sp. n. is shorter than in B. mactans . The phallus of the new species is shorter than in B. mactans . The vesica configuration of B. geometroides sp. n. is conspicuously different from that of all other congeners. Compared to B. mactans , the vesica of B. geometroides sp. n. has a globular 1st diverticulum (it is elongate and bilobate in B. mactans ), a markedly shorter 2nd medial diverticulum bearing smaller cornuti, a conspicuously broader and more elongate 3rd medial diverticulum bearing smaller cornuti, and a shortly conical 5th medial diverticulum bearing weak scobination whereas that of B. mactans is broadly globular and bears short but robust triangular cornuti. The basal plate of the vesica ejaculatorius of the new species is narrow stick-like whereas it is broadly triangular in B. mactans .

Description. External morphology of adults ( Figs 1–3 ). Forewing length 17–19.5 mm in males. Male antenna shortly bipectinate. Body slender. Head and thorax deep yellow. Tegula and patagia with suffusion of red scales. Forewing broad, triangular with elongate apex and oblique tornus. Forewing ground color deep yellow with thin red stripes between veins. Pattern blackish-grey. Subbasal spot comma-shaped.Antemedial line zigzagged, strongly angled medially. Medial line S-like curved, with dentate inner margin, connected to antemedial line medially. Postmedial line S-like curved, dentate on veins. Postmedial area with diffuse longitudinal streaks of various lengths connected to postmedial line proximally. Cilia deep yellow. Hindwing pale yellowish, with diffuse grey medial transverse line waved medially and represented by dark grey streaks on veins and pale grey suffusion between them (suffusion absent in pale specimens). Abdomen pale yellow. Male genitalia ( Fig. 18 ). Uncus elongate, narrow, slightly downcurved distally, tapered subapically, with small claw-shaped tip. Arms of tegumen wide (length to width ratio 2.5:1), with concave dorsal margins, fused subapically. Vinculum equal in length to tegumen, more or less U-like shaped with short pointed tip. Valva elongate, dilated subapically. Costa with triangular and apically rounded medial process directed ventrad having somewhat concave outer margin. Distal membranous lobe rounded. Sacculus narrow, basal process short, narrowly triangular, straight. Distal saccular process with dilated base and two short, narrow and apically rounded lobes projected distally. Juxta consisting of two lateral plates divided by thin membranous commissure; basal lobe of each plate wider and shorter than apical one. Phallus short (in proportion to tegumen-vinculum complex length), slightly dilated distally, with short coecum. Main chamber of vesica more or less globular, shorter than phallus, membranous. 1st medial diverticulum globular, membranous. 2nd medial diverticulum short, broadly conical and bearing short cornuti medially and scobination distally. 3rd medial diverticulum broadly conical and somewhat curved subapically, longer and wider than 2nd one, bearing short cornuti medio-laterally and scobination distally. 4th diverticulum absent. 5th medial diverticulum short with tapered tip, bearing weak scobination laterally. Basal plate of vesica ejaculatorius narrow, stick-like.

Female unknown.

Distribution. Endemic to Taiwan Island. Known from Taitung and Kaohsiung Counties.

Etymology. The specific epithet refers to the external similarity of the new species to members of the family Geometridae due to its slender body, shortly bipectinate male antenna and wide wings.

Figures

FIGURES 1–9. Barsine spp.: adults. Depositories of the specimens: 1–3 and 5–9 in MWM/ZSM; 4 in TFRI (photo by S. Wu).

FIGURES 18–21. Barsine spp.: male genitalia. The specimens dissected are deposited in MWM/ZSM.