Teloganodes barathyae Sivaruban, Martynov, Srinivasan & Isack, 2022

Martynov, Alexander V., Sivaruban, T., Palatov, Dmitry M., Srinivasan, Pandiarajan, Barathy, S., Isack, Rajasekaran & Sartori, Michel, 2022, Contribution to the knowledge of Teloganodidae (Ephemeroptera, Ephemerelloidea) of India, ZooKeys 1113, pp. 167-197 : 167

Teloganodes barathyae Sivaruban, Martynov, Srinivasan & Isack sp. nov.

Figs 12 , 13 , 14 , 15

Material examined.

Holotype: ♀ larva, India, Tamil Nadu, Theni District, Kurangani Hills, Kottakudi River , 10.0809°N, 77.2552°E, 632 m a.s.l., 28.x.2020, Pandiarajan Srinivasan & Isack Rajasekaran leg., ZSI-SRC/I/E/652 . Paratypes: 2 larvae, ibid., 28.x.2020, Pandiarajan Srinivasan & Isack Rajasekaran leg., ZSI-SRC/I/E/653 (1 larva), AMC ZN 230 (1 larva) .

Etymology.

The new species is named in honour of Dr S. Barathy, an assistant professor in the Department of Zoology, Fatima College, Tamil Nadu, India, who contributed to the study aquatic insects of India.

Description.

Mature larva. Body length up to 5.4-5.7 mm without cerci; cerci length subequal to body length. General colouration of dorsal side of head, thorax, and terga I-IX brownish to blackish; tergum X yellowish to whitish; ventral side of the head and thorax pale, sterna I-VIII with submedian black tinges; sternum IX pale (Fig. 12A-C, F ); legs light brownish; femora light brownish with two distinct maculae (Fig. 14A-C ); basal segment of cerci black; apical parts of cerci somewhat blacked out.

Head. Lateral margins of head fringed with a row of long, stout setae, forked near base and with pointed apices, which run from posterior margin of eyes to labrum; anterior margin of clypeus with numerous stout setae of the same type (Fig. 12E ). Antennae short, 0.8 times head width, flagellum with 13-14 segments. Dorsal part of male eyes reddish.

Mouthparts. Labrum compact, ca 2.4 times wider than long, with smooth anterior emargination; dorsal surface with a transversal band of numerous feathered setae (Fig. 13C ). Mandibles slender; middle of outer margin with one long, stout seta or without seta (when absent, probably broken). Right mandible (Fig. 13A ) with inner incisor composed of two teeth; prostheca reduced, comprised of a cluster of thin setae; a small row of six long, stout, hair-like setae below mola and a bunch of short, thin setae above mola. Left mandible (Fig. 13B ) inner incisor with two teeth inserted transversely, one smaller and pointed, other large and rectangular; prostheca small with three short and long setae; no setae below mola. Number of teeth of both mandibular outer incisors undetermined due to their wear in type specimens. Maxilla (Fig. 13F ) slender, canine completely worn, its shape undetermined, two dentisetae serrated on the inner margin and three long setae on inner apical region, and cluster of long, simple setae at crown; inner margin at the base of lacinia, with a long, feathered seta dorsally and 4-5 setae of the same type ventrally; maxillary palp greatly reduced up to protuberance with seta. Superlinguae laterally angular, with a row of long, feathered setae at apex (Fig. 13D, I ). Submentum well developed laterally; glossae and paraglossae partially fused; paraglossae larger than glossae; labial palp three-segmented, articulation between all three segments well visible; segments I and II subequal in length; segment III ca 1.8 times as long as wide (Fig. 13E, G, H ).

Thorax. Pronotum with three pairs of rounded tubercles: SMs, SLs, and Ls. Mesonotum with three pairs of tubercles: two pairs of SMMs and LAs (lateral anterior tubercles), and an unpaired MP tubercle (Fig. 12C, D ).

Forefemur (Fig. 14A ) moderately broad, ca 2.4 times longer than wide; outer margin with a regular row of long, stout, hair-like setae. Dorsal surface with submarginal row of numerous short, stout setae with divergent margins (some of setae divided near apex into two rounded lobes); same stout setae scattered over whole dorsal surface; inner margin with a regular row of long, stout hair-like setae, this row continuing on dorsal surface to near articulation with trochanter; transverse row of stout setae absent. Dorsal surface of fore tibia with oblique regular row of long, stout, hair-like setae and solitary hair-like setae; outer margins of tibia with a regular row of long, stout, hair-like setae (Fig. 14E ).

Middle and hind femora with ornamentation similar to foreleg (Fig. 14B-D ). Middle and hind tibiae with a row of long and stout, hair-like setae on outer margin; dorsal surface with oblique row of long, stout, hair-like setae; also scattered short, stout setae with divergent margins (some of the setae divided near apex into two rounded lobes) present on dorsal surface along outer margin.

Tarsal claw hooked, bearing four medial denticles and two subapical denticles on opposite sides of claw; dorsal and ventral surface of claw with a row of 3-5 subapical, hair-like setae (Fig. 14F, G ).

Abdomen. Median tubercles on terga I-X present; on tergum I poorly developed; on terga II-IV moderately developed; on terga V-X most developed. In dorsal view tubercles I-IX broad and rounded apically, tubercle X distinctly slender and bluntly pointed (Fig. 15A, B ). Median tubercles with short, stout setae (Fig. 15C ). Posterolateral projections present on segments II-IX; slightly marked on segments I-VI; most distinct on segments VII-IX (Fig. 12F ). Submedian and sublateral areas of terga VI and VII with differently sized (mainly medium-length and long) stout setae with slightly or moderately divided apices.

Gills present on abdominal segments II-VI. Gill II with dorsal lamella operculate and covering others, oval with margin entire; gills II-V with well-developed flabelliform ventral lobe; gills III-V with dorsal lamella incised medially (Fig. 15D ); gill VI with dorsal lamella entire (Fig. 15E ).

Central portion of cerci with elongate stout setae with bluntly pointed apices and few long, hair-like setae; stout setae length less than half length of the corresponding segment (Fig. 15F ).

Winged stages. Unknown.

Distribution.

Western Ghats (Tamil Nadu, India).

Habitat.

The same as for D. molinerii sp. nov.

Diagnosis.

Larva of T. Teloganodes barathyae sp. nov. can be distinguished from other species of Teloganodes by the following combination of characters: (i) dorsal surface of labrum with a transversal band of numerous feathered setae; (ii) inner incisor of the left mandible with two teeth inserted transversely, one smaller and pointed, the other large and rectangular; (iii) superlinguae angular laterally, with a row of long, feathered setae at apex; (iv) forefemur moderately broad, ca 2.4 times longer than wide; outer margin with regular row of long, stout, hair-like setae; without any combination of thin and stout setae in a row; (v) forefemur bears submarginal row of numerous short stout setae with divergent margins, (some of them divided near apex into two rounded lobes); same stout setae scattered over whole dorsal surface; (vi) fore femur without transverse row of stout setae; (vii) median tubercles on terga I-X, on tergum I poorly developed; on terga II-IV moderately developed; on terga V-X best developed; in dorsal view tubercles I-IX broad and rounded apically, tubercle X distinctly slender and bluntly pointed; (viii) posterolateral projections on segments II-IX, segments VII-IX well developed but not extremely.

Larvae of this new species can be distinguished for other Indian representatives of Teloganodes by: (i) shape of superlinguae; (ii) length of antennae; (iii) absence of transversal row of stout setae on forefemur; (iv) shape of forefemur; (v) shape of median tubercles of abdominal terga.

Figures

Figure 12. Larva of Teloganodes barathyae Sivaruban, Martynov, Srinivasan & Isack, sp. nov., paratypes A total view, dorsal view B total view, ventral view C head and thorax, dorsal view D pronotum, dorso-lateral view E head, dorsal view F abdomen, ventral view. Abbreviations: white arrows show tubercles.

Figure 13. Larva of Teloganodes barathyae Sivaruban, Martynov, Srinivasan & Isack, sp. nov., paratypes. A, B mandibles C labrum D hypopharynx E labial palp F maxilla G labium H stout setae on glossa I superlingua.

Figure 14. Larva of Teloganodes barathyae Sivaruban, Martynov, Srinivasan & Isack, sp. nov., paratypes A fore femur B middle femur C hind femur D outer margin of hind femur E fore tibia F, G tarsal claw, ventral F and lateral G view. Abbreviations: black arrows show subapical denticles and setae.

Figure 15. Larva of Teloganodes barathyae Sivaruban, Martynov, Srinivasan & Isack, sp. nov., paratypes A abdomen, dorsal view B abdomen, lateral view C median tubercle of abdominal tergum VI D gill V E gill VI F setae of caudal filament.