Thalerosphyrus meghalayensis Selvakumar & Chandra

Selvakumar, C., Chandra, Kailash, Sivaramakrishnan, K. G. & Jehamalar, E. Eyarin, 2017, A new species of Thalerosphyrus Eaton 1881 (Ephemeroptera: Heptageniidae: Ecdyonurinae) from India, Zootaxa 4350 (1), pp. 84-90: 85-89

publication ID

https://doi.org/10.11646/zootaxa.4350.1.4

publication LSID

lsid:zoobank.org:pub:B94FA9DC-2974-4C15-ADB2-511BF9C23F43

persistent identifier

http://treatment.plazi.org/id/DB2E3E16-FFFD-8604-FF17-614EFDDFBA9B

treatment provided by

Plazi

scientific name

Thalerosphyrus meghalayensis Selvakumar & Chandra
status

n. sp.

Thalerosphyrus meghalayensis Selvakumar & Chandra  n. sp.

( Figs 1–21View FIGURES 1 – 3View FIGURES 4 – 10View FIGURES 11 – 16View FIGURES 17 – 21)

Material examined. Holotype: 1 larva, INDIA, Meghalaya, East Khasi Hills district, Lawsohtun, Umjasai Nala , 25°30'56.16" N, 91°51'20.16" E, 1707 m, 27.ii.2016, coll. E.E. Jehamalar (Reg. No. 5485/H13)GoogleMaps  . Paratypes: 4 larvae, same data as holotype (Reg. No. 5486/H13)GoogleMaps  ; 3 larvae, East Khasi Hills district, Sangmain, Umpaimmaw Nala , 25°32'31.49" N, 91°51'3.6" E, 1767 m, 08.iii.2016, coll. E.E. Jehamalar (Reg. No. 5487/H13)GoogleMaps  ; 4 larvae, East Khasi Hills district, Lumparing, Umrisa Nala, 25°33'11.48" N, 91°53'3.59" E, 1707 m, 27.ii.2016, coll. E. E. Jehamalar (Reg. No. 5488/H13); 1 larva, East Jaintia Hills district, Narpuh Wildlife Sanctuary, Jamchera village stream, 25°05'31.99" N, 92°21'39.1" E, 234 m, 11.iii.2016, coll. E.E. Jehamalar (Reg. No. 5489/H13).GoogleMaps 

Description. Larva. Body length 7 mm and cerci length 10 mm (full grown female larva). Dorsal and ventral side colour pattern as in Figs 1–3View FIGURES 1 – 3.

Head. Labrum greatly expended laterally, 3x as broad as long, with narrow and somewhat acute apexes ( Fig. 4View FIGURES 4 – 10); dorsal surface and anterior margin covered with long and thin setae; ventral surface with a long median arch of 20 strong and pointed setae ending close to anterior margin. Hypopharynx with robust lingua bearing a tuft of small setae, superlinguae densely covered with long and thin setae replaced before apex by very small setae up to lower part of superlinguae ( Fig. 5View FIGURES 4 – 10). Left mandible ( Fig. 6View FIGURES 4 – 10) with 11–12 fimbriate setae below inner incisor and 6 long simple and thin setae below mola. Right mandible ( Fig. 7View FIGURES 4 – 10) with 10–11 fimbriate setae below inner incisor and 9 long simple and thin setae below mola. Crown of galea-lacinia of maxillae composed of 19–20 comb-shape setae, median ones bearing 10–12 teeth ( Fig. 8View FIGURES 4 – 10). Labium with glossae rhomboid, clearly concave on their inner and outer margins near apex, dorsal surface with numerous stout setae and numerous thin and simple setae ( Figs 9–10View FIGURES 4 – 10).

Thorax. Pronotum moderately expanded laterally and posteriorly ( Fig. 1View FIGURES 1 – 3). Femora with a row of setae on outer margin; outer margin of fore tibia with few thin setae on proximal fourth, mid tibia with a row of thin setae on outer margin almost to tarsi ( Figs 11–13View FIGURES 11 – 16). Bristles on upper face of hind femora with subparallel or slightly convergent margins, apex truncate or rounded ( Fig. 14View FIGURES 11 – 16). Outer margin of hind tibia with a row of 12–13 pointed bristles in marginal or submarginal position and one row of thin setae in marginal or submarginal position ( Fig. 15View FIGURES 11 – 16). Tarsal claw with 3–4 teeth ( Fig. 16View FIGURES 11 – 16).

Abdomen. Posterolateral expansions not developed on segment I, weakly developed on segment II, strongly developed on segment III and increasing in size up to VII where they may be as long as segment VIII, shorter on segment VIII and smaller proportionally to those of segments III ( Fig. 3View FIGURES 1 – 3). Gill I elongated with concave outer margin, more than 2 times longer than wide ( Fig. 17View FIGURES 17 – 21); gill III –VI strongly asymmetrical, wider than long ( Figs 18– 19View FIGURES 17 – 21), gill VII oval and asymmetrical with rounded apex ( Fig. 20View FIGURES 17 – 21). Posterior margin of tergites with regular pointed teeth, and numerous microdenticles ( Fig. 21View FIGURES 17 – 21). Terminal filament well developed, cerci yellowish with 4–5 white bands increasing in size towards apex; segments with whorls of stout and pointed setae.

Adult. Unknown.

Etymology. This species is named after the place of collection, Meghalaya state, India.

Diagnosis. Thalerosphyrus meghalayensis Selvakumar & Chandra  n. sp. can be distinguished from Th. vietnamensis ( Dang 1967)  by posterolateral expansions of the abdomen more or less developed, those of segment VIII always shorter than those of segment VII ( Fig. 3View FIGURES 1 – 3) and from Th. bishopi Braasch & Soldan 1986  by gill VII oval and asymmetrical with rounded apex ( Fig. 20View FIGURES 17 – 21) and superlinguae of hypopharynx densely covered with long and thin setae replaced before apex by very small setae up to lower part of superlinguae ( Fig. 5View FIGURES 4 – 10). Moreover, Thalerosphyrus meghalayensis  n. sp.

can be distinguished from other species by the following combination of characters: (i) pronotum moderately enlarged laterally ( Fig. 1View FIGURES 1 – 3); (ii) bristles on the dorsal face of hind femora truncate or rounded at apex ( Fig. 14View FIGURES 11 – 16); (iii) hind tibia with a row of thin setae ( Fig. 15View FIGURES 11 – 16) and (v) posterior margin of tergites with regularly pointed teeth, and numerous microdenticles ( Fig. 21View FIGURES 17 – 21).