Tapinoma onaele, Shakur & Mangaly & Baidya & Bagchi, 2024

Shakur, Mohammad Abdus, Mangaly, Paul, Baidya, Pronoy & Bagchi, Sumanta, 2024, A new species of the genusTapinoma Foerster, 1850 (Hymenoptera: Formicidae) from the Western Ghats, India, Asian Myrmecology (e 017005) 17, pp. 1-6 : 2-5

Tapinoma onaele sp. nov.

http://zoobank.org/ BADE3C04-17E4-43E7- BC59-2471F49B7EB6

Fig. 1

Type Material:

Holotype worker - India: Karnataka, Kodagu district, Virajpet , 12.181754°N, 75.814091°E (± 10 m), 917 m alt., leaf litter extraction, 02.ii.2021, Mohammad Abdus Shakur Leg. (IISc).

Paratypes: 2 workers; India: Karnataka, Bengaluru urban district, IISc Bangalore , 13.019865°N, 77.567646°E (± 30 m), 939 m alt., Hand collection, 23.i.2023 & 24.i.2023 ; 12 workers; India: Karnataka, Bengaluru urban district, IISc Bangalore , 13.019865°N, 77.567646°E (± 30 m), 939 m alt., Hand collection, 10.ii.2024 & 11.ii.2024, Mohammad Abdus Shakur Leg. 1 worker; India: Karnataka, Dakshina Kannada district, Puttur , 12.760601°N, 75.2050073°E (± 30 m), 115 m alt., Hand collection, 09.xii.2023 ; 1 worker; India: Kerala, Palakkad district, Palakkad , 10.782537°N, 76.652701°E (± 30 m), 120 m alt., Hand collection, 24.ii.2024, Paul Mangaly Leg. (IISc, GKVK) .

Measurements (n = 17 workers; holotype measurements in parenthesis) - LES:0.03 – 0.05 (0.04); EL: 0.13 – 0.15 (0.14); EW: 0.07 – 0.09 (0.08); ES: 0.19 – 0.24 (0.20); HW: 0.43 – 0.49 (0.45); HL: 0.58 – 0.63 (0.59); OOD: 0.25 – 0.30 (0.25); OCD: 0.06 – 0.09 (0.07); CL: 0.10 – 0.13 (0.12); SL: 0.59 – 0.65 (0.63); PnL: 0.25 – 0.3 (0.28); ML: 0.22 – 0.28 (0.26); PpL: 0.12 – 0.14 (0.12); PdL: 0.24 (0.24); CI: 0.70 – 0.81 (0.76); OI: 0.54 – 0.61 (0.6); SI: 1.27 – 1.39 (1.4); PDI: 0.51 – 0.58 (0.51).

Description.

Head: Head longer than broad by 1.3 times, posterior margin convex, slightly narrow than anterior, sides almost parallel, posterolateral corners rounded, vertex convex. Eyes relatively large, longer than wide, placed just below the midline of head. Antennae 12 segmented, scape long, surpassing posterior margin of head by at least 1/3 of its length. Frontal carinae present. Anteromedial clypeal margin concave, posterior clypeal margin concave between the anterior margin of antennal socket cavities. Masticatory margin of mandibles with 9 – 10 teeth and denticles, size gradually decreasing from apical to basal tooth, 3 rd tooth smaller than 4 th tooth.

Mesosoma: Mesonotal and metanotal groove distinct, dorsum of pronotum and mesonotum even, propodeum bulges distinctly above mesonotum; dorsal surface of propodeum slightly convex, dorsal face shorter than declivitous face, propodeal angle with a distinct ridge or carina, with high acute angle; metanotal spiracle placed on the dorsolateral margin in lateral view; propodeal spiracles present laterally and posteriorly near the declivitous face.

Petiole and Gaster: Petiolar scale small, inclined anteriorly. Gaster overhanging petiole.

Color, Sculpture, and Pilosity: Whole body brownish, head and gaster darker than mesosoma, almost black, petiole and legs lighter than mesosoma with a hint of yellow. Whole body with finely coriaceous sculpture. Anterior clypeal margin with setae, medial pair longer and lateral setae short; mandibles with faint striations and numerous long suberect setae; 1 st gastral tergite covered in short appressed setae, lacking erect setae; remaining gaster tergites with setae present; head and antennal scapes covered in sparse short appressed setae.

Variation in workers: Posterolateral corners of the head of some paratype workers are angulated, unlike other workers with rounded posterolateral corners. The propodeum appears to be swollen in profile in a few paratype workers.

Etymology

The specific epithet “ onaele ” refers to leaf litter in the Kannada language of the type localities, reflecting the nesting habitat of this species. This term is used to draw attention to the importance of maintaining the leaf litter in the coffee plantations, a crucial microhabitat in sustaining the local myrmecofauna ( Shakur 2021).

Differential diagnosis. This new species belongs to the Tapinoma lugubre species group. Tapinoma onaele sp. nov. can be distinguished from T. himalaicum and other species in this group by (1) Larger body size and longer scapes (SI>1.3) ( T. himalaicum has shorter scapes, SI – 1.2); (2) dorsal surface of propodeum is convex and rises above the mesonotum (does not rise and is in line in T. himalaicum & T. wilsoni ; rises above mesonotum but is flat in T. lugubre ); (3) darker and brownish body ( T. himalaicum has a lighter body); (4) gaster darker than rest of the body (black) ( T. himalaicum has gaster concolorous with the rest of the body); (5) antennal scapes concolorous with head ( T. himalaicum has scapes lighter than head); (6) Propodeum is longer (PpL ≥ 0.12 mm) and propodeal declivity index is larger (PDI> 0.5) (Propodeum in T. himalaicum is smaller (PpL ≤ 0.1mm) and propodeal declivity index is small (PDI ≤ 0.4)).

Figures

Fig. 1. Tapinoma onaele sp. nov., Holotype, worker: (a) Head in full-face view, (b) Body in dorsal view, (c) Body in profile view.