Alfieriella senguptai Chen & Leschen, 2020

Chen, Yan-Dong, Leschen, Richard A. B., Bai, Ming & Yang, Xing-Ke, 2020, A new Himalayan species of Alfieriella (Coleoptera: Cryptophagidae), Zootaxa 4819 (3), pp. 571-581 : 572-575

Alfieriella senguptai Chen & Leschen , sp. n.

( Figs. 1–4 )

Chinese name: DZOiaeṘm (English translation: Giant dry-habitat cryptophagid)

Type material. Holotype: CHINA: male ( IZAS), ‘ China : Xizang, Ya’dong County, 3km south of the pass, 27.8008°N, 89.1447°E, wasteland, under rock, 4600m, 23.VI.2016, Hong-bin Liang & Xin-xin Li leg. ’ Paratypes: INDIA: 2 males, 3 females (1 on a slide) ( BMNH), ‘ India: Sikkim, Deutang , 14600ft, 28.IV.1924, Maj. R. W.G. Hingston leg. ’

Diagnosis. Alfieriella senguptai sp. n. is much larger than the remaining members of the genus and can be further differentiated from A. laticollis by having the combined width of the elytra wider than the pronotum; and from A. naxiana , A. senguptai has rounded pronotal sides and an apiculate antennal club; and from the similar-looking A. denticulata and A. rabinovitchi , A. senguptai has rounded posterior angles of pronotum and an incised apex of posterior section of the aedeagus.

Description. Body length: 1.82–1.90 mm; body width: 0.71–0.78 mm; body height: 0.48–0.57 mm. Body oval, elongated and convex. Light reddish brown; elytra dark brown; meso- and metaventrite and abdominal ventrites brown. Pubescence decumbent and uniseriate; length of setae on dorsal surface 0.04–0.05 mm. Punctation sparse and not well impressed over entire body; punctures on dorsal surface separated by 2–3 diameters. Space between punctures with three different types of surface sculpturing: dorsal head and pronotum colliculate; elytra and prosternum rugose; venter of head, meso- and metaventrites and femora imbricate.

Head transverse (L = 0.21–0.22 mm; WL = 1.73–1.75 [exposed portion of the retracted head]). Punctation small and sparse; distance between punctures 3× times longer than their diameter (5.20–6.00 μm). Eye reduced, not prominent; number of ommatidia about 25, diameter of ommatidium 16.00–17.00 μm. Mandible broad ( Fig. 2F ) and bidentate, lacking subapical teeth, with brushy subapical prostheca, a distinct mesal membrane and a reduced mola bearing teeth. Maxillary palpomere 4 elongate-oval, 2× longer than palpomere 3. Subgenal spine well developed.

Antenna short (L = 0.52–0.55 mm), with 10 antennomeres, and reaching 2/3 to base of pronotum ( Fig. 2A ); scape oval and enlarged; pedicel narrow but as long as scape; antennomere 3 conical and 2/3 as long as pedicel; antennomeres (A) 4–9 subequal and each slightly shorter than A3; A4 and A5 as broad as long; A6, A7, and A8 broader than long; club 1-segmented, suboval and somewhat constricted at apical 1/4, 3× longer than A3.

Pronotum slightly wider than long (L = 0.53–0.56 mm; WL = 1.05–1.07), broadest just anterior to middle; sides evenly arcuate; anterior margin weakly arcuate; posterior margin weakly rounded; anterior and posterior angles rounded. Basal groove and foveae absent. Prosternal process not extended far beyond procoxae, normal, slightly convex in lateral view; apex truncate with lateral margins parallel. Procoxal cavity externally incompletely closed.

Elytra elongate-oval (L = 1.06–1.12 mm; WL = 0.64–0.65) with anterior margin slightly broader than posterior margin of pronotum, broadest near the middle; anterior ridge present; humeral tooth present ( Fig. 2C , ht); elytral suture firmly fastened; epipleuron distinct to level of posterior margin of abdominal ventrite 3; subapical gape absent ( Fig. 2G ); punctures on elytra slightly larger than those on pronotum (9.00–10.00 μm), distance between punctures slightly longer than 3 times the diameter. Scutellar shield reduced and triangular ( Fig. 2C ). Metanotum reduced, hind wings absent ( Fig. 2D ). Mesepimeron and mesoventrite fused; mesoventrite with procoxal rests; prosternal rest absent; width of mesoventral process equal to width of mesocoxa.

Tarsi 5-5- 5 in both sexes.

Male genitalia as long as the whole abdominal ventrite (L = 0.76–0.80 mm). Penis divided into anterior and posterior sections, anterior section 1.5× longer than posterior section (L = 0.41–0.43 mm; Fig. 2H ), parallel-sided and with a well-developed marginal rim, apex rounded; posterior section with median longitudinal suture, apically incised (L = 0.21–0.22 mm; Fig. 2L ) weakly curved ventrally in lateral view ( Fig. 2I ). Tegmen with anterior arms fused with a long anterior strut (separated in Fig. 2J ), parameres long (L = 90.20–95.00 μm) ( Fig. 2K ), widest at base, separate and articulate, apex of each paramere with 3 long setae (L = 0.075 –0.080 mm), surface with scattered setae, apart from a distinct outside row of 4 or 5 short setae. Endophallus simple, lacking setae or spines and with weakly pigmented sclerites posteriorly ( Fig. 2L ).

Male. Protarsomeres 1–3 dilated ( Fig. 2B ).

Female. Spermathecal duct membranous.

Etymology. The specific epithet is dedicated to the Indian entomologist T. Sen Gupta for his contribution to our knowledge of the diversity of Cryptophagidae .

Comments. Sen Gupta & Crowson (1971) referred to an unpublished genus, called ‘Acryptus’, in its own tribe, contained in Sen Gupta’s unpublished PhD thesis. We borrowed specimens of this taxon from the BMNH ( Fig. 4 ). These specimens have the typical 10-segmented antenna with a large 1-segmented club shared by all described members of Alfieriella and confirm the placement of the new species in this genus. Alfieriella senguptai can also be considered as a member of Alfieriella by the absence of a pronotal bead, conspicuous subgenal spines, and articulated parameres ( Leschen 1996).

Figures

FIGURE 1. Alfieriella senguptai sp. n., holotype, habitus. (a) Dorsal view; (b) ventral view, (c) left lateral view. Scale bar = 1 mm.

FIGURE 2. Alfieriella senguptai sp. n., holotype. (A) Dorsal view of left antenna; (B) dorsal view of left front leg; (C) mesothorax and base of elytra, ht = humeral tooth; (D) metathorax; (E) gut contents; (F) dorsal view of right mandible; (G) apex of elytra. (H–L) Male genitalia. (H–I) aedeagal apodeme and aedeagus, dorsal (H) and left lateral (I) view; (J) parameres and tegmen; (K) parameres; (L) aedeagus. sc1: scale bar for A = 0.2 mm; sc2: scale bar for B = 0.2 mm; sc3: scale bar for C–D = 0.2 mm; sc4: scale bar for E = 0.05 mm; sc5: scale bar for F–G = 0.1 mm; sc6: scale bar for H–I = 0.2 mm; sc7: scale bar for J = 0.2 mm; sc8: scale bar for K–L = 0.1 mm.

FIGURE 3. Surrounding environment where the holotype of Alfieriella senguptai sp. n. was collected (photo taken by Yijie Tong).

FIGURE 4. Paratypes of Alfieriella senguptai sp. n. housed in BMNH (taken by Keita Matsumoto).