Caissa yunnana, Wu & Wu & Han, 2020

Wu, Jun, Wu, Chun-Sheng & Han, Hui-Lin, 2020, A new species of the genus Caissa Hering, 1931 from Yunnan, China (Lepidoptera, Limacodidae), ZooKeys 951, pp. 83-89 : 83

Caissa yunnana sp. nov. Figures 1 , 3

Holotype.

♂, China, Yunnan Province, Lvchun County, Mt. Huanglian, 27-31.VII.2018, leg. HL. Han, J. Wu, MR. Li [NEFU], genit. prep. WuJ-069-1.

Paratypes.

3♂, same data as holotype [NEFU], genit. prep. for one dissected paratype WuJ-068-1.

Description.

Adult (Fig. 1 ). Wingspan 29-31 mm in male. Head white, labial palpus and patagium brown. The male antennae filiform, brown; the thorax mixed white and brown, the tegula white with brown margin; dorsally abdomen yellowish brown to dark brown, ventrally white or yellowish brown. Forewing ground color dark brown, with unequal-sized white patches; light-colored basal patch small, not connected with inner patch; orbicular spot large, broadly connected to the larger inner patch; two medium-sized white patches lie in the middle of the forewing, near the inner margin, distal to the medial line which runs from the costal margin at 1/2 the distance from the wing base, to the inner margin at 1/3 from the wing base; arcuate postmedial line from the costal margin at 2/3 from the wing base to the tornus; postmedial area with 4 large whitish spots, the tornus with 2 whitish spots; subterminal line curved strongly inward, from apex to the outer margin at 3/5 from the apex, combined with postmedial line on R5; terminal area white, forming a nearly right triangle. Hindwing brown and mixed with a small amount of red, anal area light brown with oblong dark blotch with a white spot inside. The white spot is much smaller than the encircling brown.

Male genitalia (Fig. 3 ). Uncus slender, with a small subapical spur. Gnathos well developed, very straight rod-shaped terminal part with slightly curved apex. The base of valva wider than middle; the cucullus wide and round; costa simple, slightly shorter than valve; sacculus sclerotized and shorter than costa, sacculus process bifurcated, distinctly incurved and hook-shaped. Juxta asymmetrical, the right side of terminal part strongly sclerotized, U-like, with dense black spurs. Saccus inconspicuous. Phallus curved, weakly sclerotized, bent into an obtuse angle in the middle; 1/2 of the terminal part with a strongly sclerotized wedge-shaped area; the terminal part of carina sclerotized, short, cone-shaped; vesica with big cyst, surface covered with small spines, with a big, sclerotized cornutus.

Female genitalia. Unknown.

Diagnosis.

The new species is similar in appearance to C. caissa (Fig. 2 ), but can be distinguished from the latter by the characters of the forewing and male genitalia, as follows. In C. yunnana the light-colored basal patch is small, not connected with the inner patch; orbicular spot large, connected with the inner patch (Fig. 1 ); in C. caissa , the basal patch is bigger than in C. yunnana , and it is broadly connected with the inner patch, but not connected with the small orbicular spot. Also, the tornus of C. yunnana contains only 2 whitish spots, but the same location in C. caissa contains 4 whitish spots. The color of the hindwing in C. yunnana is darker than in C. caissa .

In the male genitalia, the new species clearly differs from C. caissa (Fig. 4 ) by the sclerotized area of the sacculus being wider than the same area in C. caissa ; in C. yunnana the sacculus process is bifurcate, distinctly incurved and hook-shaped, whereas in C. caissa it is short, and although bifurcate, barely hooked. The phallus of C. yunnana differs from that of C. caissa by the middle being bent into an obtuse angle, 1/2 of the terminal part with a strongly sclerotized wedge-shaped area, and the vesica with a big cyst and a big sclerotized cornutus. The phallus of C. caissa is smoothly curved, and the vesica is membranous, without a cyst or cornutus.

Distribution.

China (Yunnan Province: Mt. Huanglian) (Fig. 5 ).

Etymology.

The species is named for its type locality in Yunnan Province, China.

Bionomics.

The moths fly in July. The specimens were collected with a light trap close to a broad-leaved forest with ferns and shrubs (Fig. 6 ).

Figures

Figures 1 - 4. Caissa spp., adults: 1 C. yunnana sp. nov., male, holotype 2 C. caissa Hering, 1931, male, holotype (after Solovyev and Saldaitis 2014); male genitalia: 3 C. yunnana sp. nov., holotype 4 C. caissa Hering, 1931, holotype (after Solovyev and Saldaitis 2014). Scale bars: 1 mm. (BP: basal patch; IP: inner patch; ML: medial line; OS: orbicular spot; PL: postmedial line; SL: subterminal line; TA: terminal area).

Figures 5, 6. Map and habitat of C. yunnana sp. nov. 5 Collecting site of C. yunnana sp. nov.: Yunnan Prov., Mt. Huanglian (red dot) 6 Collecting site close to a broad-leaved forest with ferns and shrubs.