Rinacapritermes silvius Amina & Rajmohana, 2022

Amina, Poovoli, Rajmohana, Keloth, Dinesh, K. P. & Asha, Gopalan, 2022, Integrative taxonomic studies on Rinacapritermes Amina & Rajmohana, n. gen. (Blattodea: Isoptera: Termitidae) with two new species from India, Zoosystema 44 (3), pp. 109-124 : 112-114

Rinacapritermes silvius Amina & Rajmohana n. sp.

( Figs 1 ; 3 ; 7A ; Table 1 )

urn:lsid:zoobank.org:act:8C629647-1999-45D7-BAB7-F16A1C792D1C

TYPE MATERIAL. — Holotype (Soldier). India • Kerala, Ernakulam, Urulanthanni ( Thattekadu Bird Sanctuary ); 10°7’41”N, 76°45’18”E; 5.I.2015; Amina Poovoli leg.; Colony code:ZSI/WGRC/IR/INV/4610. Paratypes (12 soldiers, 10 workers). India • 10 soldiers, same data as for holotype • 10 workers; same data as for holotype • 2 soldiers; Kerala, Idukki (Thekkady, in Periyar Tiger Reserve ); 9°27’43”N, 77°14’12”E; 6.IV.2013; K. Rajmohana & party leg.; Colony code: ZSI/ WGRC /IR/INV/4611 .

Sequenced specimens. Same as paratypes.

ETYMOLOGY. — The species epithet name is derived from the latin term ‘silvius’ meaning forest as the new species was predominant in forested habitat.

DNA BARCODE. — Rinacapritermes silvius Amina & Rajmohana , n. gen., n. sp. is showing sister relationship with Rinacapritermes abundans n. sp. exhibiting genetic divergence of 7.3% to 8.3% for COI gene ( Fig. 4 ). Both the species can easily be distinguished morphologically (see key below) and both the species type localities are isolated in range of distribution ( Fig. 5 ).

DISTRIBUTION IN INDIA. — From two adjoining districts of Kerala (Ernakulam and Idukki); could be a limited-range endemic species restricted to south of Palghat Gap.

DESCRIPTION

Imago

Not known

Soldier ( Fig. 1 A-E; Table 1 )

Monomorphic. Head capsule pale yellowish brown; fontanelle gland area pale yellow; antennae paler than head; labrum translucent at arterial and lateral part and pale yellow on rest; left mandible blackish brown; right mandible reddish brown; legs and body whitish yellow.

Head Capsule. Moderately hairy with long and a few short hairs. Antennal segments with long and short hairs on entire surface; labrum with a few hairs on anterior part; postmentum with a very few short hairs at distal third. Anterior margin of pronotum with 5-8 long hairs. Body densely hairy with long hairs; legs covered with long hairs, more concentrated at last tarsal segments.

Head capsule in dorsal view. Subrectangular; sides substraight, slightly narrowing at anterior end; minimum width being at base of mandibles; posterior margin rounded. Frons sharply inclining in front; median suture of head short, extending up to 1/4 of head-length from posterior margin; fontanelle transverse, situated anteriorly at distal 1/5 of head; fontanelle gland large, extending beyond middle of head. Antennae with 15 segments; segment 2 longer than 3; segment 4 slightly longer than or sometimes subequal to 3; segment 3 sometimes shortest; 5-10 gradually increasing in length and remaining segments subequal. Labrum slightly asymmetrical; anterior margin substraight with broad based, robust and long antero-lateral points. Mandibles strongly asymmetrical; left mandible strongly twisted at middle; with blunt apex. Right mandible blade-like with sharp, pointed apex, facing upward; inner margin of right mandible incurved at middle region; apical blade substraight. Postmentum club-shaped; length more than 1/2 of head length; with a narrow waist lying posteriorly.

Title. Pronotum saddle-shaped, anterior and posterior margin without any notch. Legs with 3:2:2 apical tibial spurs; outer spur not very distinct.

Abdomen. Elongated; cerci short; 2 segmented.

Worker (n = 5)

Monomorphic. Head capsule, antennae, postclypeus whitish yellow; thorax and legs paler than head; abdomen translucent with intestinal contents showing through. Head capsule moderately hairy with many long and short hairs, post clypeus with long hairs and body sparsely hairy with a few long hairs and very short hairs. Total body length 3.9-4.40 mm.

Head. Subcircular; length to tip of labrum 1.13-1.23 mm, length to base of mandible 0.68-0.76 mm and maximum width 0.88-0.92 mm; width of head capsule widest at base of mandibles. Epicranial suture slightly distinct; fontanelle plate translucent and oval. Antennae with 14-15 segments; segment 3 shortest; segment 2 longer than 3 and 4. Postclypeus swollen; almost straight anteriorly and rounded posteriorly; length less than half of width (length 0.19-0.22 mm; width 0.45-0.47 mm).

Mandible ( Fig. 1F ). As for genus.

Digestive tube. As for genus.

Pronotum. Saddle-shaped (length 0.24-0.26 mm; width 0.48-0.53 mm); anterior and posterior lobe without notch. Legs with 3:2:2 apical tibial spurs; dorsal spur of foretibia at times indistinct; foretibia somewhat swollen.

REMARKS

Dorsal spur of fore tibia is sometimes indistinct. So both the 3:2:2 and 2:2:2 conditions are seen in the soldiers as well as the workers of the same colony.

Figures

FIG. 1. — Rinacapritermes silvius Amina & Rajmohana, n. gen., n. sp.: A, soldier body dorsal view; B, soldier head dorsal view; C, soldier head profile; D, soldier’s labrum; E, soldier’s postmentum; F, worker left and right mandible. Scale bars: A, B, 0.5 mm; C, F, 0.3 mm; D, 0.1 mm; E, 0.2 mm.

FIG. 3. — Digestive tube of Rinacapritermes silvius Amina & Rajmohana,n. gen., n. sp. worker:A, dorsal view; B, left lateral view; C, right lateral view; D, ventral view; E, worker’s enteric valve armature. Scale bars: A-D, 0.5 mm; E, 20 μm.

FIG. 7. — A, pronotum of Rinacapritermes silvius Amina & Rajmohana,n. gen.,n. sp. soldier; B, pronotum of Indocapritermes aruni Chhotani,1997 soldier C, mandible of Rinacapritermes abundans Amina & Rajmohana, n. gen., n. sp. soldier D, mandible of Indocapritermes aruni soldier. Scale bars: 0.2 mm.

FIG. 4. — Maximum likelihood tree based on 663 bp of mitochondrial COI gene (*represents the bootstrap values above 50%).

FIG. 5. — Distribution map of Rinacapritermes Amina & Rajmohana, n. gen. species.