Euconocephalus helleri Tiwari and Diwakar, 2024

Tiwari, Chandranshu & Diwakar, Swati, 2024, The Orchestra Nocturne: Description For Six New Katydid Species From India (Orthoptera: Tettigoniidae), Zootaxa 5405 (2), pp. 227-245 : 235-237

Euconocephalus helleri Tiwari and Diwakar sp. n.

( Fig. 4 )

Material examined: Holotype: Male. INDIA: Assam, Hollangapar Gibbon Wildlife Sanctuary , Jorhat ~ 120 m a.s.l. 2020, Coll. Chandranshu Tiwari, Department of Environmental Studies, University of Delhi, 110007 (Delhi), India . Paratype: Assam, Hollangapar Gibbon Wildlife Sanctuary , Jorhat ~ 120 m a.s.l., 2021 Coll. Chandranshu Tiwari (1 ♂) .

Type locality. Hollangapar Gibbon Wildlife Sanctuary , Jorhat, Assam, India.

Measurements (length in mm): Body 43.12; fastigium 4.5; tegmen 46.65; pronotum 7.11; fore-femora 4.75; mid-femora 6.56; hind-femora 21.83; fore-tibia 5.13; mid-tibia 7.04; hind-tibia 23.9; file 1.4.

Distribution: Crepescular - Nocturnal. Bushes and shrubs, fallow land, gardens on the forest edge.

Seasonal occurrence: The species was recorded from the type locality during the monsoon and wet post-monsoon period.

Etymology: The species epithet is in recognition of Dr. Klaus Gerhard Heller, who has made an invaluable contribution in the taxonomy and bioacoustics of Tettigoniidae .

Differential diagnosis: The species is similar to Euconocephalus mucro ( Haan 1843) but differs in the following traits: Tegmen rounded with slight downward curve and cerci tip curved inward in a hook-like with a sharp spine. Both species can also be differentiated in the field based on their calls, E. mucro produces a distinct chirping call while E. helleri produces a continuous trill ( Tiwari and Diwakar 2019, 2023a).

Description:

Male: Body large and slender. Head: Head triangular in profile, rugose dorsally. Fastigium of vertex conical, elongated, 4.5 mm, Fastigium separated from frons by a notch with a distinct ventral tubercle present at the base of fastigium. Antennae unicolor Eyes suboval and prominent. Pronotum: Pronotum larger than the head; pronotum broader distally, compressed ventrally, anterior dorsal margin concave, posterior margin rounded; transverse sulcus distinct before the middle of pronotum, median carina weak, lateral carinae of pronotum present. Lateral lobes of pronotum longer than high, humeral sinus distinct. Prosternum armed with a pair of spines, mesosternal and metasternal lobes triangular. Thoracic auditory spiracle large, oval, completely hidden under the lateral lobe of pronotum. Legs: genicular lobes of pro femora armed by a single spine on inner side and unarmed on outer side; mid genicular lobe armed by a single spine on both inner and outer side; post genicular lobe armed by bispinose on both side. Fore coxae armed by a forward outward projecting spine. All femora dorsally unarmed. Pro- and mid-femora armed with 4 spines ventrally on the inner margin. Hind-femora ventrally armed with 10 spines on outer and 12 spines on inner margin. Pro- and mid-tibia dorsally unarmed. Pro-tibia ventrally armed with 6–6 spines on inner and outer margin. Mid-tibia armed ventrally with 7 and 8 spines on outer and inner margin respectively. Hind tibia dorsally armed with 5 spines on outer and 6 spines on inner margin. Hind tibia ventrally armed with 14 spines on outer and 16 spines on inner margin. Single dorsal pair of spurs and two ventral pairs (inner small and outer large) of spurs present on the apical region of hind tibiae. Wings. Tegmina longer than hind wings extending beyond the hind wing; apices obliquely rounded. Wings reaching beyond the middle of hind tibiae when folded. Stridulatory file on the ventral side of left tegmen with 100 teeth. File medially curved and raised, narrow on distal and proximal ends.

Male genitalia. Supra-anal plate triangular with dorsal basal groove, apex subobtuse. Subgenital plate long, both lateral and middle ridges well developed; apical margin with triangular excision. styles conical and long. Cerci thick with two incurved apical teeth, dorsal tooth shorter than ventral tooth.

Female. Unknown. Supposedly similar to E.mucro .

Coloration. Green to Yellow Green when alive. Antennae yellow to pale green. Lateral margin of fastigium of vertex on both sides with narrow yellow band which extends on the vertex above eye level and reaching up to the posterior margin of pronotum. Tegmen appears green/yellow when live with anterior external margin of the tegmen pale or translucent. All femora same color as tegmen. Tibia pale yellow to white. Claws and tarsal joints pale.

Depositories: The specimen is deposited in the Department of Environmental Studies, Faculty of Science, University of Delhi.

Figures

FIGURE 4. Euconocephalus helleri (a) habitus, (b) dorsal view of fastigium, (c) dorsal view of pronotum, (d) ventral view of sternum, (e) lateral view of abdomen and cerci (f) dorsal view of right tegmen, (g) supra-anal plate, (h) subgenital plate, (i) scanning electron microscope image of stridulatory file.