Abraxas pusilla Butler, 1880

Gayen, Subrata & Chandra, Kailash, 2023, A new distributional range of Abraxas antipusilla Inoue, 1995 (Lepidoptera: Geometridae) from Eastern Himalaya, India, Zootaxa 5228 (2), pp. 187-194 : 188-189

Abraxas pusilla Butler, 1880

( Fig. 1A–H )

Abraxas pusilla Butler, 1880 , Ann. Mag. nat. Hist., (5) 6 (33): 225. Type Locality: Darjeeling [ India]

Abraxas (Calospilos) kanoi Inoue, 1970 , Spec. Bull. lepid. Soc. Jap., 4: 206.

Abraxas (Calospilos) pusilla Inoue, 1995 , In: Haruta et al., Tinea , 14 (suppl. 2): 122, pl. 120, figs. 7–8.

Diagnosis: Forewing length 16.39–20.08 mm in males, 17.70–18.27 mm in females. Male of Abraxas pusilla and A. antipusilla share similar wing patterns, but the latter is much larger in size than the former one. However, the male genitalia of A. pusilla may easily be distinguished by its broad valvae with acute apical protrusion on the dorsal margin and short, straight aedeagus.

Redescription of male and female genitalia: In male genitalia uncus elongated, slender with spatulate apex; costal basal process stout, slightly curved, apically pointed and setose, a short sclerotized ridge present from base till the middle of its length; valvae broad, bulged at base, dorsal margin highly curved ending in a short, slender, acute and apically round process, dorsal flap broad, comb shaped, narrow at base with marginal irregular dentations, outer margin slightly curved inwardly generating into a short, stout ventral process with two uneven minute apical spines; juxta broad, triangular; saccus broad, slightly triangular ( Fig. 1C ); aedeagus short, stout, straight, apically blunt with a minute subapical spine ( Fig. 1D ).

In female genitalia papilla analis elongated, roundish, having long setae; anterior apophysis ¼ length of posterior apophysis ( Fig. 1E ); ostium bursae well sclerotized and ‘V’ shaped lamella antevaginalis ( Fig. 1G ); antrum broad, sclerotized; colliculum long, broad and sclerotized; ductus bursae short, broad, straight and slightly sclerotized; corpus bursae ellipsoid, slightly sclerotized; signum round with 15 to 17 long spines, some of them are bifurcated; medial spines are sparse and small ( Fig. 1F ).

Variation: The species is highly variable in size and pattern; median region of forewing is completely suffused with grey scales, conjoined with the postmedial line. Single specimen ( Fig. 1B ) appears from the collection, which is almost identical to the Abraxas peregrina Inoue, 1995 but smaller in size.

Material examined: India: [Arunachal Pradesh]: Dihang Dibang Biosphere Reserve: 1 ♁, Anini Base, 28.7871 °N, 95.9094 °E, 1675 m, 03.V.2017, legit. S. Gayen & Party; 1 ♁, Ebalin , 29.0167 °N, 95.8070 °E, 1609 m, 18. IV. 2018, legit. R. Ranjan & G. N. Das; 1 ♁, Ahipu, 28.7716 °N, 95.9488 °E, 3800 m, 12.VI.2018, legit. S. Gayen & Party; Tawang: 1 ♀, Lumla, 91.7290 °N, 27.5340 °E, 1982 m, 01.VI.2019, legit. Dibyajyoti Ghosh & team; [Uttarakhand]: Askot Wildlife Sanctuary: 1 ♀, 2 ♁, Chipla Kedar, 27.9663 °N, 88.4259 °E, 4216 m, 30.VI.2018, legit. Sanyal & Nandi Das; [Sikkim]: Kyongnosla Alpine Sanctuary: 1 ♀, Padamchen, 27.2402 °N, 88.7672 °E, 2215 m, 31.V.2017, legit. K. Mondal & Party; KBR: 1 ♁, Gnathang, 27.2992 °N, 88.8177 °E, 3716 m, 30.V.2017, legit. K. Mondal & Party; 1 ♀, Yoksum, 27.3786 °N, 88.2208 °E, 1879 m, 20.XI.2019, legit. A. K. Sanyal & Party; 1 ♀, 1 ♁, Yoksum, 27.3786 °N, 88.2208 °E, 1879 m, 23.XI.2019, legit. A. K. Sanyal & Party; 1 ♀, Khongtay, 27.3794 °N, 88.2268 °E, 1950 m, 28.XI.2019, legit. A. K. Sanyal & Party; 1 ♀, Nerdang, 27.3145 °N, 88.3064 °E, 850 m, 04.XII.2019, legit. A. K. Sanyal & Party; 1 ♀, Ringhim, 27.4906 °N, 88.5402 °E, 1510m, 10.XII.2019, legit. A. K. Sanyal & Party; [West Bengal]: Neora Valley National Park : 5 ♀, Neora, 27.0863 °N, 88.6597 °E, 2083 m, 06.XI.2016, legit. K. Mondal and Party; 2 ♀, 4 ♁, Lava, 27.0863 °N, 88.6597 °E, 2083 m, 03.IX.2016, legit. K. Bhattarcharyya and Party; 5 ♀, 1 ♁, Rishop, 27.1073 °N, 88.6512 °E, 2136 m, 05.IX.2016, legit. K. Bhattarcharyya and Party; 1 ♀, Rishop, 27.1024 °N, 88.8483 °E, 760 m, 06.XI.2016, legit. K. Bhattarcharyya and Party; 1 ♀, Ashaley Camp, 27.0109 °N, 88.7701 °E, 695 m, 19.VI.2017, legit. K. Bhattarcharyya and Party; Singalila National Park : 2 ♀, Palmajua, 27.0707 °N, 88.0907 °E, 1909 m, 03.XI.2018, legit. K. Bhattarcharyya and Party; 1 ♁, Dhotrey, 27.0499 °N, 88.1093 °E, 2531 m, 05.XI.2018, legit. K. Bhattarcharyya and Party; 1 ♁, Sirikhola, 27.1322 °N, 88.0766 °E, 1883 m, 17.X.2018, legit. K. Bhattarcharyya and Party; 1 ♀, 2 ♁, Rimbik, 27.1141 °N, 88.1105 °E, 1905 m, 18.X.2018, legit. K. Bhattarcharyya and Party; 1 ♀, Gairibash, 27.0509 °N, 88.0336 °E, 2494 m, 21.V.2018, legit. K. Bhattarcharyya and Party; 1 ♁, Manedara, 27.1147 °N, 88.1 °E, 2168 m, 22.X.2018, legit. A. K. Sanyal and Party.

Distribution: India: Arunachal Pradesh, Himachal Pradesh, Sikkim, Uttarakhand, West Bengal ( Chandra and Sambath 2013) Global: Nepal (Haruta 1995).

Remarks: Among the congeners, this is the smallest species.

Figures

FIGURE 1. Wing pattern, genitalia structures and distribution range of Abraxas pusilla Butler 1880: (A–B) Dorsal view; (C) Genitalia capsule; (D) Aedeagus; (E) Female genitalia; (F) Close up on the signum; (G) Close up on the lamella antevaginalis; (H) Distribution map of all currently known records from Indian Himalayan Region.