Discotettix (Discotettix) sumatrensis Skejo, Pushkar et Tumbrinck, 2022

Skejo, Josip, Pushkar, Taras I., Kasalo, Niko, Pavlović, Marko, Deranja, Maks, Adžić, Karmela, Tan, Ming Kai, Rebrina, Fran, Muhammad, Amira Aqilah, Abdullah, Nurul Ashikin, Japir, Razy, Chung, Arthur Y. C. & Tumbrinck, Josef, 2022, Spiky pygmy devils: revision of the genus Discotettix (Orthoptera: Tetrigidae) and synonymy of Discotettiginae with Scelimeninae, Zootaxa 5217 (1), pp. 1-64 : 44-47

Discotettix (Discotettix) sumatrensis Skejo, Pushkar et Tumbrinck sp. n. ( Figs 30–32 )

Vernacular name: Sumatran Spiky Pymgy Devil

Type locality. Indonesia: Sumatra: Jambi province, 35 km N of Sungai Penuh, NP Kerinci-Seblat, Mt. Kerinci , 1500–2000 m a.s.l.

Material examined.

Type material. HOLOTYPE: 1♀ Indonesia: Sumatra: Jambi province, 35 km N of Sungai Penuh, NP KerinciSeblat, Mt. Kerinci , 1500–2000 m a.s.l. 8–22.XI.1999. Leg. A.V. Gorochov ( Figs 30 , 31 ) ( ZISP) ; PARATYPES: 1♀, 1♂ Indonesia: Sumatra: Jambi province, 35 km N of Sungai Penuh, NP Kerinci-Seblat, Mt. Kerinci , 1500–2000 m a.s.l. 8–22.XI.1999. Leg. A.V. Gorochov ( Figs 30 , 31 ) ( ZISP) .

Type series depository. ZISP: Orthoptera collection of the Zoological Institute of the Russian Academy of Sciences (St. Petersburg), Russia.

Additional material. 1♂ Indonesia: Sumatra: Siolak Daras.: Korinchi Valley (= Kerinci) 3100 ft. (= 945 m a.s.l.) III.1914. identified as D. selysi by K. Günther, photographs ( Fig. 32 ) barcode NHMUK012498526 available at https://data.nhm.ac.uk/dataset/56e711e6-c847-4f99-915a-6894bb5c5dea/resource/05ff2255-c38a-40c9-b657- 4ccb55ab2feb/record/8248606 ( NHMUK) .

Etymology. The new species is named sumatrensis (adjective masculine, third, vocal declension) after the type locality, Sumatra Island.

Distribution and habitat. The species is currently known only from Mt. Kerinci, Sumatra, the highest vulcano in Indonesia and the Sumatra’s highest peak (above 1500 m). The mountain is surrounded by lush forest. It is an isolated mountain, so there is a chance of D. sumatrensis being a local endemic. Distribution is shown in Fig. 3 .

Specific diagnosis. The species is morphologically similar to D. kirscheyi sp. n. from Borneo and can be easily distinguished from other species. From D. scabridus the species differs by: (I) frontal costa bifurcates between the eyes, (II) FM well developed, (III) MM triangular and elevated, (IV) MML triangular and elevated, (V) lateral and humeral carinae granulated. The species can be distinguished from D. belzebuth by the following characters: (I) smaller body size, (II) peculiar coloration of antennae with lighter colored segments, (III) antenna with 7 th segment being the widest (not the 8 th as in most of the other species), (IV), pronotum with smaller triangular projections, except the digitate FM, (V) hind femur with large lappets (smaller in D. belzebuth ), and (VI) ovipositor generally slenderer than in D. belzebuth . The species differs from D. selysi by (I) peculiar coloration of antennae with lighter colored segments, (II) widened antennal segments narrower than in D. selysi, (III) pronotal disc with numerous triangular protuberances and (IV) large lappets of hind femur (medium sized in D. selysi ). The species is similar to D. kirscheyi sp. n. but can be easily distinguished from the mentioned by (I) longer FM, (II) stronger pronotal projections, (III) specialized and colorful antennal segments and (VI) smaller body size.

Holotype description. ( Figs 30 , 31 )

General features. Medium sized, robust species (body length 11.7–13.5 mm); pronotum granulated and wrinkled, with one digitate FM on anterior margin and numerous triangular protuberances on dorsal and lateral sides.Almost the entire body (except eye, labrum, fore and mid tarsi, second and third segments of hind tarsus, inner side of the hind femur) covered with numerous small tubercles ( Figs 31 , 32 ). Macropronotal.

Coloration. Body dark brown, almost completely covered by numerous small tubercles with lighter apices. Pronotum dark brown with darker projections and protuberances, tubercle-shaped ML of humeral angles on shoulders lighter. Antenna darkish with yellowish colored apical segments (after widened segments 8 th black with yellowish apex, 9 th yellow, 10 th –13 th black. Maxillary palpi dark brown. The visible part of the tegmen dark brown and without spots. Legs generally dark brown with lighter rings and patches. Fore and mid femora and tibiae dark brown with numerous small tubercles with lighter apices, fore and mid tarsi darkish, second segment with light ring near middle; 1 st tarsal pads whitish, claws brown. Hind femur dark brown with numerous small tubercles with lighter apices. Hind tibia in ♀ dark brown with two light rings, one in basal part, and another—in distal third; while in ♂ blackish brown, with weak (not distinguishable) light rings. 1 st tarsus of hind leg darkish, with light colored ring near apex, pads whitish; third segment blackish brown with a light ring near the middle, claws brown. Tergites, sternites, epiproct, and cerci dark brown.

Head. In dorsal and frontal views, vertex 2.6 times in ♂, 2.5 times in ♀ as wide as an eye. Fossula deep. Lateral ocelli situated at the level of the lower margin of the compound eye. In frontal view, frontal costa narrow, bifurcated between the lateral ocelli into a distinctly divergent, finely granulated facial carinae, concave in about the middle of its length, forming sand-clock-shaped scutellum. Frontal costa in ♂ 1.6 times, in ♀ 1.5 times, wider than antennal groove, 1.25 times in ♂, 1.2 times in ♀ as long as antennal groove width. Antennal groove considerably below the lower margin of a compound eye ( Fig. 30B ). Antenna 13-segmented: scapus (1 st antennomere) and pedicel (2 nd antennomere) massive; basal segments (3 rd to 6 th) dark, elongated and circular in cross-section; central segment 7 th strongly widened and the widest antennal segment (3–3.6 times as long as wide), 8 th segment reduced, weakly pennate, dark, and with yellow apex; apical segment 9 th small, yellow, elongated, and pennate, smaller than the subapical and much larger than the rest of the apical segments; apical segments 10 th to 13 th again dark reduced, small, elongated in comparison to other species of the subgenus, and the borders between them barely visible. Antennomeres 3 rd to 9 th bearing saw-like margins, because of the presence of large basiconic sensilla.

Pronotum. Pronotum wrinkled and granulated, covered by numerous small and medium-size tubercles. Posterior process of pronotum extended beyond hind knees for less than half of hind femur length. Disc of the pronotum depressed behind the well-developed shoulder, slightly descending backwards. Pronotum with 6 unpaired projections of variable size on medial carina (large digitate FM and 5 medium-sized medial), 3 pairs of FL projections, 7 pairs of more or less distinct mediolateral, 3 pairs of lateral and 1 pair of VL projections (well seen in profile). Prozona subsquare: prozonal length/width ratio 1.0 in ♂, 1.15 in ♀. Anterior margin of pronotum projected into a large digitate FM protuberance directed mainly forwards than upwards, covering whole vertex above. Prozonal and extralateral carinae in the prozona surpassing the anterior margin of the pronotum as dentiform FL1 and FL2. FL2 more distinct. Downwards, at the anterior margin of the pronotum less developed dentiform FL3. Behind FM medial carina extended along the whole length of the pronotum, with 5 unpaired large and small medial projections (better seen in profile): behind digitate FM, in the prozona, first small triangular PM protuberance. Next large triangular protuberance, between spinae of lateral lobes— MM1, then MM2, MM3 and MM4) protuberances, generally decreasing in size towards apex of pronotal process (sometimes posterior projection almost wanting). Smaller and lower then medial: 7 distinct double triangular MML. Mediolateral projections in the prozona present as more or less distinct PML1 double tubercle as a posterior elongation of prozonal carinae, and on same line PML2 double tubercle near border between prozona and metazona. Small MML1 between the shoulders, and large MML2 projection on the place where most Tetrigidae (Tetriginae) species have a posthumeral spot. Next three— MML3, MML4 and MML5 smaller, decreasing caudad. In the prozona lateral projections present as small double triangular PL1 and PL2 tubercles situated between the sulci on the line joining extralateral and humero-apical carinae. Іn metazona, humero-apical carinae forming moderately sharp humeral angle, projected outwards as a small ML tubercle of humeral angle, behind this point joining the external lateral carinae. Apex of posterior pronotal process in dorsal view shallowly excised. Lower part of lateral lobe with serrate anterior and posterior margins, elongated as spine-like VL, directed outwards ( Fig. 30A, C, E, F ).

Wings. Visible part of tegmen slightly elongated, oval with champlevé surface, visible part 3.2 times as long as wide in ♂ and 2.9 in ♀; ratio of maximum width of mid femur (without teeth) / visible part of tegmina width 1.6 times in ♂ and 1.29 times in ♀. Hind wing almost reaching the apex of the posterior pronotal process (ending 1.2–1.3 mm before it).

Legs. Femora robust, compressed laterally, surface from smooth to rough, dorsal and ventral margins roughly serrate. Fore and mid femora bearing one genicular tooth on the knees on each margin, and additionally 3 strong teeth on the upper carina and 2–3 on the lower margin, lower usually smaller than upper; teeth on fore femur equal or smaller than on mid femur. Upper and lower margin of hind femur finely serrated, with 2–3 lappets on each margin, and with numerous small tubercles. Lateral area of hind femur with weak carinae that have 2–3 outgrowths, especially in ventro-external carina. Genicular teeth larger than antegenicular. Fore femur length/width ratio 3.9 in ♂ and 3.8 in ♀. Mid femur length/width ratio 4.1 in ♂ and 4.2 in ♀. Hind femur length/width ratio 3.0 in ♂ and 3.2 in ♀. Both sides of the upper margin of hind tibia finely serrated, additionally with 2–3 outer and 2–3 inner (bit larger) teeth.

Abdominal apex. Male subgenital plate in ventral view with shallowly excised apex, 1.4 times as long as wide, in lateral view 2.4 times as long as tall ( Fig. 31A, B ). Female subgenital plate in ventral view with triangular protrusion in middle of posterior margin. Ovipositor elongated, upper valve 5.0 times as long as wide. Lower valve of ovipositor 6.0 times as long as wide (maximal width) ( Fig. 31C, D ). Cerci length/width ratio near base 1.8 in ♀ and 1.9 in ♂.

Measurements (male paratype and female holoype). BL ♂ 11.7 mm, ♀ 13.5 mm; PnL ♂ 12.8 mm, ♀ 15.6 mm; PnW ♂ 6.63 mm, ♀ 7.86 mm; AnL ♂ 7.2 mm, ♀ 7.2 mm; TL ♂ 1.6 mm, ♀ 2.0 mm; TW ♂ 0.91 mm, ♀ 1.1 mm; fFL ♂ 3.5 mm, ♀ 3.8 mm; fFW ♂ 0.89 mm, ♀ 1.01 mm; mFL ♂ 3.3 mm, ♀ 3.8 mm; mFW ♂ 0.8 mm, ♀ 0.91 mm; hFL ♂ 6.4 mm, ♀ 7.5 mm; hFW ♂ 2.13 mm, ♀ 2.49 mm; OvL ♀ 2.4 mm; AnL/fFL ♂ 2.05, ♀ 1.89; VW ♂ 1.91 mm, ♀ 2.05 mm; EW ♂ 0.73 mm, ♀ 0.82 mm; VW/EW ♂ 2.6, ♀ 2.5; SW ♂ 0.36 mm, ♀ 0.41 mm; AgW ♂ 0.23 mm, ♀ 0.27 mm; ScW ♂ 0.29 mm, ♀ 0.23 mm; SW/AgW ♂ 1.6, ♀ 1.5; SW/ScW ♂ 1.25, ♀ 1.2; As—L/W ♂ 3.6, ♀ 3.3; PrzW ♂ 4.11 mm, ♀ 5.62 mm; PrzL ♂ 4.09 mm, ♀ 4.91 mm; Prz—W/L ♂ 1, ♀ 1.15; TL/TW ♂ 3.2, ♀ 2.9; mFW/TW ♂ 1.6, ♀ 1.29; fFL/fFW ♂ 3.9, ♀ 3.8; mFL/mFW ♂ 4.1, ♀ 4.2; hFL/hFW ♂ 3, ♀ 3.2; T1L/T3L ♂ 1.15, ♀ 1.07.

Figures

FIGURE 3. Distribution map of Discotettix species.

FIGURE 30. Discotettix sumatrensis Skejo, Pushkar, et Tumbrinck sp. n. A, E) male paratype; B–D, F) female holotype. A: Paratype dorsal view, B. Holotype frontal view, C. Holotype dorsal view, D. Holotype labels, E. Paratype in lateral view. F. Holotype in lateral view. Specimens photographs by V. Loktionov, lables photograph by Sergey Storozhenko. Reproduced with the author’s permission. Scale bar = 2 mm. C. Labels.

FIGURE 31. Abdominal apex of Discotettix sumatrensis Skejo, Pushkar, et Tumbrinck sp. n. A, B. male paratype; C, D. female holotype. Photographs by Sergey. Storozhenko. Reproduced with the author’s permission. Scale bar = 0.5 mm.

FIGURE 32. Discotettix sumatrensis Skejo, Pushkar, et Tumbrinck sp. n., male from NHMUK (012498526). A. right lateral view; B. dorsal view; C. labels. Photography NHMUK, copyright The Trustees of the Natural History Museum, London.