Strattis pascoei, Devi & Ray & Ramamurthy, 2016

Devi, Salam Rita, Ray, D. C. & Ramamurthy, V. V., 2016, Descriptions of three new species of Strattis Pascoe, 1883 (Coleoptera: Curculionidae: Cryptorhynchinae) from the Indian subcontinent, Zootaxa 4085 (2), pp. 199-218 : 201-204

Strattis pascoei sp. nov.

( Figs 1–3 , 10, 13, 16, 19, 22–26, 49–57, 114, 123–127)

Description. Length: 3.81–5.70 mm; width: 1.82–2.77 mm.

Integument reddish black, slightly paler at antennae; finely sculpture; with dense whitish, dusty grey, and dark brown recumbent scales; pronotum with mostly whitish scales, variegated with two pairs of blackish spots, one apically, another medially and a distinct patches basally; elytra with dusty greyish scales a little beyond middle, variegated with whitish scales apically; ventrally with whitish scales, except on ventrites 3 to 5 which is with blackish scales; legs with mixture of whitish and blackish scales ( Figs 1, 2, 3 ). Head finely punctate, but hidden with dense recumbent scales ( Fig. 10); frons narrower than base of rostrum, without any distinct frontal fovea. Rostrum almost straight, 2.95–3.01 x as long as broad, slightly constricted at point of antennal insertion, basal half with dense scales, sparser apically, apical portion smooth and shining medially. Antennae inserted laterally at middle ( Fig. 10), scrobe ventrolateral; scape 2.60–2.63 x as long as broad; funicle segments with fine, elongate, whitish setae, article 1 of funicle 1.53–1.58 x as long as broad, much broader than other segments, nearly as long as article 2 of funicle; article 2 of funicle 1.79–1.82 x as long as broad; articles 2 to 7 of funicle progressively decreasing in length and increasing in breadth, articles 1 and 2 of funicle longer than broad, articles 3 to 7 of funicle transverse; club compact, ovate, segments distinctly visible, 1.63–1.65 x as long as broad ( Fig. 50 ). Pronotum strongly transverse, 0.68–0.70 x as long as broad, subparallel to middle, abruptly constricted a little beyond middle, shallowly constricted towards apically, each lateral side medially with small forwardly-directed projection, dorsum without any median carina, apex slightly rounded, base bisinuate (Figs 13, 49); ocular lobe present ( Fig. 3 ). Scutellum bare, subquadrate or cordate, anterior margin distinctly constricted, finely granulate, nearly as long as broad (Fig. 16). Elytra 1.20–1.22 x as long as broad, without distinct humeri, parallel to middle and shallowly constricted apically, with distinct subapical callus; abruptly elevated below scutellum, roundly convex medially, sinuate basally and slightly rounded apically; stria 1.98–2.04 x as broad as interstria, with punctures subrectangular; protuberances basally on interstria 1 more distinct than others, interstriae 1 to 3 with sparse blackish scales basally, interstria 9 slightly costate.

Ventrally, prosternal canal ending between middle of meso-coxae; receptacle nearly U-shaped, cavernous, slightly transverse ( Fig. 114 ). Metasternum without median sulcus. Anapleural suture without distinct sclerolepidia. Abdomen with ventrite 1 1.15–1.23 x as long as ventrite 2, suture between ventrites 1 and 2 sinuate, ventrite 2 1.75–1.81 x as long as ventrites 3 and 4 combined; ventrite 3 nearly as long as ventrite 4; and ventrite 5 1.0–1.14 x as long as ventrites 3 and 4 combined (Fig. 19). Legs with the femora edentate, sulcate beneath, sulci bare; meso-tibiae crenulate basally at outer margin ( Fig. 51 ) and becoming parallel with inner margin, tibial apex without uniform outer setose fringes; uncus prominent ( Fig. 52 ). Abdomino-femoral stridulatory structures present, with stridulatory file on the inner lateral aspect of meta-femora ( Figs 125–127 ), with patches of plectra on lateral side of ventrite 1 ( Figs 123, 124 ). Female genitalia with spermatheca narrowed, hook shaped; cornu pointed apically; ramus apart from collum ( Figs 22 , 53 ); hemisternite elongate, stylus cylindrical, 2.9 2–3.12 x as long as broad, with few elongate setae apically ( Figs 23 , 54 ); spiculum ventrale sclerotised, pouch, with arms narrowed, Yshaped, with spicule straight, narrowed medially; apically with two plates of 8th sternum, plates set with dense, stout erect spines, ( Figs 24 , 55 ). Tergite VII 0.68–0.69 x as long as broad, constricted medially, with two patches of wing binding spine structures ( Figs 25 , 56 ); tergite VIII crenulate apically, with elongate, erect setae, 1.0–1.17 x as long as broad ( Figs 26 , 57 ).

Material examined. Holotype, female, India: Tamil Nadu, Nilgiri Hills , Coll. H. L. Andrewes ( NPC) . Paratypes, 3 females: with the same data as holotype (NFIC-2); Myanmar, Coll. A. K. Downing (NPC-1).

Remarks. This species can be easily differentiated with its typical combination of scales, viz: pronotum with whitish scales, variegated with two pairs of blackish spots, one apically, another medially and with distinct patches basally; elytra with dusty greyish scales beyond middle, variegated with whitish scales apically; also with distinct constriction on anterior margin of scutellum. Sparse blackish scales on ventrites 3 to 5 resemble S. srilankaiensis , but these blackish scales on ventrites 3 to 5 are much darker and prominent in this new species.

Etymology. This new species is named in honour of the late Francis Polkinghorne Pascoe who described this genus and in recognition of his contributions towards Coleoptera . He was born in Penzance, England on 1st September 1813. He served as assistant surgeon in the Navy and later he devoted himself to Entomology, Coleoptera in particular. He has various research publications in renowned journals and a large collection composed of some 2500 type specimens deposited in the Natural History Museum, London. He became a Fellow of the Entomological Society and Linnaean Society and also a member of the Société Entomologique de France. He died in Brighton on 20th June 1893.

Figures

FIGURES 1 – 9. Habitus (dorsal, ventral and lateral view) of Strattis Pascoe: Figs 1 – 3. S. pascoei sp. nov., Figs 4 – 6. S. maculatus sp. nov., Figs 7 – 9. S. srilankaiensis sp. nov.

FIGURES 49 – 57. Line illustration of S. pascoei sp. nov.: Fig. 49. Pronotum, Fig. 50. Antennae, Fig. 51. Basal portion of tibae, Fig. 52 Tibial apex, Fig. 53. Spermatheca, Fig. 54. Stylus, Fig. 55. Spiculum ventrale, Fig. 56. Tergite VII, Fig. 57. Tergite VIII.

FIGURES 114 – 122. SEM images: Figs 114 – 116. Mesosternal receptacle of: Fig. 114. S. pascoei sp. nov., Fig. 115. S. maculatus sp. nov., Fig. 116. S. srilankaiensis sp. nov.; Figs 117 – 120. S. srilankaiensis sp. nov., Fig. 117. lateral view of rostrum, Fig. 118. anapleural suture, Fig. 119. Scutellum, Fig. 120. Tubercles on scutellar suture; Fig. 121. S. maculatus sp. nov., meso-leg; Fig. 122. Tibial apex, showing uncus (UN) and mucrouncus (MUN).

FIGURES 123 – 127. Abdomino-femoral stridulatory organs of S. pascoei sp. nov., Fig. 123. Ventrite 1 (V 1) and ventrite 2 (V 2), showing their sculpturing differences, Fig. 124. Ridges on ventrite 1, which act as plectrum, Fig. 125. Meta-femora, showing the longitudinal convex area on the inner lateral aspect, Fig. 126. File like structures on convex ridge of femora; Fig. 127. Higher magnification of Stridulatory file.

FIGURES 22 – 26. Female genitalia of S. pascoei sp. nov.: Fig. 22. Spermatheca, Fig. 23. Stylus, Fig. 24. Spiculum ventrale, Fig. 25. Tergite VII, Fig. 26. Tergite VIII.