Lepisiota binghami

Identification
Lepisiota binghami distinctly differs from other known species of the genus Lepisiota from India. It differs from the bicoloured species Lepisiota pulchella in the sculpture of body, distribution of setae on the body, and size. Lepisiota pulchella workers have reticulate-punctate sculpture on the dorsum of head and mesosoma with gaster microreticulate and subopaque while the head of L. binghami is faintly microreticulate and shiny, most mesosoma without reticulation, gaster smooth and shiny. Mesosoma of L. pulchella has abundant pilosity whereas L. binghami has very less pilosity. Lepisiota pulchella is comparatively larger (HL 0.58–0.64, WL 0.83–0.91) than L. binghami (HL 0.51–0.56, WL 0.69–0.76) (here we are not considering measurements of Wachkoo et al. (2021) as they might have also considered specimens with less prominent characters of L. pulchella as discussed in personal communication).

Lepisiota binghami differs from another similar species Lepisiota chutimae in the sculpture of mesosoma and head, colouration of gaster, and petiole height. The dorsum of promesonotum is microreticulate and subopaque, the dorsum of metanotum and propodeal spines are reticulate in L. binghami whereas the dorsum of mesosoma is completely smooth in L. chutimae; dorsum of head is comparatively clear microreticulate with feeble striation below compound eyes in L. binghami whereas L. chutimae is about completely smooth. The first gastral segment is yellowish-brown to brown and the remaining part of the gaster is black in L. binghami whereas the gaster is completely dark brown in L. chutimae. The petiole of L. chutimae is higher (PH 0.33–0.35) than L. binghami (PH 0.24–0.28) (Jaitrong et al. 2022).

Distribution based on Regional Taxon Lists
Oriental Region: India.

Nomenclature

 * . Lepisiota binghami Harshana & Dey, 2022: 6, fig. 1 (w.) INDIA (Kerala).

Type Material

 * Holotype worker. INDIA: Kerala: Palakkad (Nelliyampathy), 10°32ʹ56”N 76° 41ʹ08”E, 865 m, 27.V.2019, Coll. Anooj S.S.
 * Paratype workers. 1 worker with same data as holotype; Thrissur (Peechi), 10°31ʹ48”N 76°20ʹ48”E, 78 m, 7 workers, 30.V.2019, Coll. Anooj S.S. (type specimens deposited in NPC, New Delhi).

Description
Worker

Head: Head slightly longer than broad, sides and posterior margin weakly convex, posterolateral corners rounded and head covered with appressed pubescence (Fig. 1C); posterior margin of head with 2–3 erect setae (including a pair of erect setae between lateral ocelli); palp formula 6,4 and third maxillary segment from base longest of all segments; mandible triangular with five teeth on masticatory margin, from apex third and fifth tooth are smaller than others; antennae 11 segmented, scape extending to posterior margin of head about 1/3rd of its length, third antennal segment smaller than second and fourth segment, length of second segment is about equal to combined length of third and fourth segment, antennae covered with decumbent to suberect pubescence; antennal insertions touching posterior clypeal margin; clypeus dorsally convex, subcarinate medially, anterior clypeal margin convex, posterior clypeal margin with a pair of long erect setae, anterior margin with two pairs of long erect setae with a downwardly directed long median seta; compound eyes broadly oval, positioned at about midlength of head and covering about 1/3rd of lateral cephalic margin; three ocelli present but faintly visible.

Mesosoma: Promesonotum convex in profile view, higher than metanotum but about as high as propodeum (Fig. 1A); mesometathorax constricted; propodeum armed with broad blunt spines and propodeal declivity slanting; the distal end of foretibia with pectinate spur and basitarsus with hairy notch; pronotum with 2–4 (two in most specimens) long erect yellowish setae, mesonotum with 1–2 (two in most specimens) erect yellowish setae and propodeum with 0–1 (absent in most specimens) erect yellowish setae (Fig. 1A); mesosoma having very sparse and decumbent pubescence.

Metasoma: Petiole upright, dorsally bispinose and deeply emarginate (Fig. 1A), lateral sides slightly convex; gastral segments with numerous yellowish erect setae mostly on posterior half and having very sparse, decumbent pubescence; acidopore well-developed and fringed with hairs.

Sculpture and colour: Head faintly microreticulate and shiny; region below the compound eyes feebly striate; dorsum of promesonotum microreticulate and subopaque while dorsum of metanotum and propodeal spines reticulate (Fig. 1B); mesometapleuron rugose while pleuron of propodeum subopaque; upper half of propodeal declivity longitudinally striate; mandible, clypeus, propleuron, gaster smooth and shiny; Body bicoloured; head, mesosoma, petiole, first gastral segment yellowish-brown to brown and remaining part of gaster black.

Measurements and indices (N = 5; holotype values within parentheses) - EL: 0.16 (0.16); HL: 0.51–0.56 (0.56); HW: 0.45–0.50 (0.50); MML: 0.24–0.28 (0.28); PH: 0.24– 0.28 (0.28); PRW: 0.32–0.35 (0.35); SL: 0.57–0.61 (0.59); TL: 2.12–2.37 (2.12); WL: 0.69–0.76 (0.76); CI: 87–90 (90); OI: 31–34 (31); REL: 28–30 (28); SI: 118–129 (118).

Etymology

The patronymic name honours entomologist Charles Thomas Bingham for his pioneering extensive work on Indian Hymenoptera including ants.