Paraparatrechina neela, Sahanashree & Punnath & Rajan Priyadarsanan, 2024

Sahanashree, Ramakrishnaiah, Punnath, Aswaj & Rajan Priyadarsanan, Dharma, 2024, A remarkable new species of Paraparatrechina Donisthorpe (1947) (Hymenoptera, Formicidae, Formicinae) from the Eastern Himalayas, India, ZooKeys 1203, pp. 159-172 : 159-172

Paraparatrechina neela sp. nov.

Figs 3 , 4

Material examined.

Holotype: worker, point mounted. Original label: “ India: Arunachal Pradesh, East Siang District, Yingku Village , 28.4606 ° N, 94.8841 ° E, 803 m a. s. l., aspirator, 7 May 2022, Priyadarsanan DR leg. ”; AIMB / Hy / Fr 25006 . Paratype: 1 worker; same data as holotype; AIMB / Hy / Fr 25007 .

Worker description.

Measurements (in mm) and indices:

Holotype worker: EL 0.14; HL 0.50; HW 0.42; SL 0.51; PW 0.29; WL 0.53; GL 0.66; TL 1.69; CI 84; REL 28; SI 121.

Paratype worker: EL 0.13; HL 0.59; HW 0.43; SL 0.50; PW 0.28; WL 0.57; GL 0.66; TL 1.76; CI 72; REL 22; SI 116.

Diagnosis.

Paraparatrechina neela sp. nov. has the following unique combination of characters: 1) body opaque and largely metallic blue, except antennae, mandibles, and legs; 2) total length <2 mm; 3), eyes large relative to head length (REL> 22); 3) scape with appressed pubescence and scape surpasses posterior margin of head by approximately length of first 4 funicular segments; 4) propodeal dorsal face short and angular, with a long declivitous face.

Head. In full-face view (Fig. 3 A ), subtriangular, 1.2 × longer than wide; posterior margin of head convex. Mandible triangular, masticatory margin with 5 teeth (Fig. 4 A ), 1 long apical tooth followed by acutely triangular tooth, 2 minute denticles and a triangular basal tooth: maxillary palp and labial palp with palp formula, PF (6: 4). Antennae with 12 segments; scape surpasses posterior margin of head approximately by the length of first 4 funicular segments. In profile view, clypeal disc projects, medially carinate. In full-face view, anterior clypeal margin convex. Eyes large, REL 22–28, oval; ocelli present, only median ocellus visible, other two ocelli relatively concealed, indistinct (Fig. 3 A ).

Mesosoma. Compact in lateral view, pronotum convex with short dorsal face in lateral view (Figs 3 C , 4 B ). Mesonotum sloping towards metanotum, propleura and mesopleura demarcated by a distinct promesonotal suture; mesopleura and metapleura demarcated by indistinct metanotal groove; propodeum raised, propodeal dorsal face short, angular, with a long declivitous face; propodeal spiracle distinct (Fig. 3 C ).

Metasoma. Petiole length 0.05 mm, strongly compressed antero-posteriorly. Gaster with 5 tergites, anterior margin concave and forming sharp edges in dorsal view (Figs 3 B , 4 D ). Acidopore distinct apically (Fig. 3 C ).

Sculpture. Body covered with fine punctures; mandibles with longitudinal striations (Fig. 4 A ); clypeus, mesopleura, and propodeal declivity smooth and shiny (Fig. 4 A – C ).

Pilosity. Short, decumbent pubescence covers most of the body. Distinctly paired dark setae present from anterior clypeal margin to propodeum; 8 pairs on head from posterior region to clypeus; 2 pairs on pronotum, 2 pairs on mesonotum, 1 pair on propodeum (Figs 3 C , 4 B ). Setae shorter on head posterior to eyes and gaster and longer on anterior of head and mesosoma.

Color. Body largely iridescent blue, with a purple tinge and white pubescence; legs and antennae brown at base, dark to yellowish brown at middle, white at the tip; mandible yellowish brown. Gaster blue in anterior region, brown towards posterior end.

Etymology.

The specific epithet neela is a noun in apposition, signifying the color blue in most Indian languages. It is used to describe the unique blue or sapphire color of this species.

Species comparison.

Paraparatrechina neela sp. nov. is easily distinguishable from all known species of Paraparatrechina by its metallic-blue body. It can be separated from P. aseta , the only other known species from the Indian subcontinent (Fig. 5 A – C ) by the following characteristics: 1) body largely metallic blue, except antennae, mandibles, and legs in P. neela (body uniformly light brown in P. aseta ); 2) in full-face view, head subtriangular with strongly convex lateral margin in P. neela (head subrectangular with gently convex lateral margin in P. aseta ); 3) anterior clypeal margin convex in P. neela (anterior clypeal margin medially concave in P. aseta ); 4) mandible with five teeth in the masticatory margin in P. neela (mandible with six teeth in P. aseta ); 5) propodeal dorsal face in lateral view raised in P. neela (propodeal dorsal margin flat and continuous with rest of mesosoma in P. aseta ). Paraparatrechina neela is similar to P. butteli bryanti ( Forel, 1916) , another Indomalayan species ( Wheeler 1919), in body size, eye length, antennal scape surpassing occipital margin, and a raised propodeal dorsal face with a long declivitous face. However, P. neela can be easily separated from P. butteli bryanti by the following characteristics: 1) body largely metallic blue in P. neela (body castaneous brown; head, thorax, and gaster with metallic reflections in P. butteli bryanti ); 2) legs with thick appressed pubescence in P. neela (legs with sparse pubescence in P. butteli bryanti ); 3) overall body opaque with fine punctures in P. neela (thorax and gaster distinctly shagreened in P. butteli bryanti ); 4) head subtriangular, longer than wide in P. neela (head subrectangular, as long as wide in P. butteli bryanti ).

Figures

Figure 3. Paraparatrechina neela sp. nov., holotype worker AIMB / Hy / Fr 25006 A head in full-face view B body in dorsal view C body in profile view.

Figure 4. Paraparatrechina neela sp. nov., holotype worker AIMB / Hy / Fr 25006 A clypeus and mandibles B mesosoma in profile view C mesosoma in dorsal view D gaster in dorsal view.

Figure 5. Paraparatrechina aseta, syntype worker A head in full-face view B body in dorsal view C body in profile view. Photo credit: Will Ericson, www. antweb. org, CASENT 0910999 (AntWeb 2023 b).