Alysson bengalensis Girish Kumar, 2020

Kumar, P. Girish, Sheela, S. & Sharma, Gaurav, 2020, Additions to the knowledge of the Tribe Alyssontini (Hymenoptera: Crabronidae Bembicinae) in India with description of two new species of the genus Alysson Panzer, Zootaxa 4861 (2), pp. 270-280 : 271-273

Alysson bengalensis Girish Kumar , sp. nov.

( Figs 1–10 )

urn:lsid:zoobank.org:act:C9751D38-2B8D-427B-9EBF-ABEE2A48C0C7

Type material. Holotype ♀, India: West Bengal, Kalimpong district, Neora Valley National Park (27° 04’ 56’’ N & 88° 42’ 02’’ E, 2189 m), 6.x.2018, Coll. S. Sheela, ZSIK Regd. No. ZSI/ WGRC /IR/INV.14401 . Paratype ♀, same collection data of holotype, ZSIK Regd. No. ZSI/ WGRC /IR/INV.14402 .

Diagnosis. This new species differs from all other species of the genus by the following combination of characters: Metasoma entirely black; propodeal enclosure apically triangular, only longitudinally carinated inside; mesosoma (except tegula brownish on outer side) entirely black, without ferruginous red markings. This new species come close to A. triangularis Krombein in having metasoma entirely black, propodeal enclosure apically triangularly pointed, and mesosoma (except tegulae brownish on outer side) entirely black, without ferruginous red markings but distinctly differs from A. triangularis in having the characters mentioned in the couplet number 5 of the key. As per the key for Chinese species by Wu & Zhou (1987), this new species comes close to A. sichuanensis Wu & Zhou and A. carinatus Wu & Zhou but differs distinctly from both. It differs from A. sichuanensis in having no creamy white to yellow spot between antennal sockets (in A. sichuanensis a yellow spot present between antennal sockets) and clypeus with a creamy white to yellow band at apical half only (in A. sichuanensis most part of clypeus yellow except its basal margin and centre black). It differs from A. carinatus in having clypeus with a creamy white to yellow band at apical half (in A. carinatus , clypeus with two yellow spots) and second recurrent vein joining to third submarginal cell (in A. carinatus , second recurrent vein joining to second submarginal cell).

Description. Holotype female ( Fig. 1–10 ). Length 7.83 mm; forewing length 6.43 mm. Colour. Black, the following parts creamy white: mandible except apex, a band at apical half of clypeus (not extending towards lateral margins of clypeus), narrow stripe along inner eye margin and extending halfway to anterior ocellus, scape beneath, fore coxa beneath, narrow streak anteriorly on fore tibia, and pair of round anterolateral spots on Gt 2. The following brown: tarsal segments, and outer sides of tegula. Wings clear except forewing with two infumated bands; outer infumated band covers most of marginal cell, apical third of first submarginal cell, second and third submarginal cells, outer half of third discoidal cell, extending toward posterior margin of wing; inner infumated band covers basal half of first discoidal cell, second discoidal cell almost entirely except apex and apex of submedial cell. Vestiture silvery, subappressed; some longer suberect setae also present on mandible, clypeus, mesopleuron, coxae and femora beneath, sides of Gt 3-6 and Gs 2-6; pygidial setae silvery. Head. Head width 1.98 × interocular distance at antennal insertions and 1.48 × that at anterior ocellus ( Fig 2 ); apical margin of clypeus ( Fig 3 ) trilobate, middle lobe larger than lateral lobes; labrum short, about as wide as lobate section of clypeus and with subtruncate apical margin; front with shallow median groove evanescent at upper half of front, with small punctures; OOL 3 × POL (in female paratype OOL 4 × POL); POL 0.36 × ocellooccipital distance. Antenna as in Figure 4 , length of antennal segments as follows, scape: pedicel: fu 1: fu 2: fu 3: fu 4: fu 5: fu 6: fu 7: fu 8: fu 9: fu 10 = 13: 7.7: 14: 13.5: 12.5: 11: 10: 10: 9.5: 9.5: 9: 12.5. Mesosoma. Pronotum dorsally with small punctures, mostly separated by about the width of the diameter of a puncture, with a crenulate groove posteriorly (groove narrowed towards middle); lateral surface of pronotum with some strong oblique rugulae on upper half, lower half mostly glabrous anteriorly; mesoscutum with small subcontiguous punctures; mesopleuron with tiny punctures separated by several times the diameter of a puncture. Dorsal side of propodeum ( Fig 6 ) with propodeal enclosure apically triangularly pointed, inner side of enclosure only longitudinally carinated, outer side of enclosure with radiating striae from outer margins of enclosure and few rugoso-reticulations towards periphery, lateral tooth well developed; posterior side of propodeum smooth on either sides of its median carina. Forewing ( Fig. 7 ) with second recurrent vein joins with third submarginal cell.

Metasoma. Gt 1 and Gt 2 almost impunctate except for sparse, scattered setae on sides ( Fig 9 ); base of Gt 1 with strong longitudinal cavities on either side, margined by strong carina.

Etymology. The species epithet is derived from the state of collection of the species, West Bengal.

Distribution. India: West Bengal ( Fig 41 ).

Figures

FIGURE 41. Distribution map of the genus Alysson Panzer from the Indian subcontinent.

FIGURES 1–10. Alysson bengalensis sp. nov. Holotype ♀. 1. Habitus, lateral view. 2. Head, frontal view. 3. Lower half of head, frontal view. 4. Antenna. 5. Head and mesosoma, dorsal view. 6. Propodeum, dorsal view. 7. Forewing. 8. Hindwing. 9. Metasoma, dorsal view. 10. Last metasomal tergite.