Eucriotettix guentheri Tan & Storozhenko

Tan, Ming Kai, Storozhenko, Sergey Yu, Hwang, Wei Song & Meier, Rudolf, 2017, Integrative taxonomy reveals two sympatric species of the genus Eucriotettix Hebard, 1930 (Orthoptera: Tetrigidae), Zootaxa 4268 (3), pp. 377-394 : 388-390

Eucriotettix guentheri Tan & Storozhenko , sp. nov.

Material examined. Holotype—male (TET.84), Singapore: Woodcutter trail, 3 November 2013, coll. M. K. Tan & H. Yeo . Paratypes (19 males and 8 females): Upper Seletar Reservoir Park , 11 September 2013, 2 males (TET.28, 30), 1 female (TET.29), coll. M. K. Tan & R. W. J. Ngiam ; NSSF interior, 14 September 2013, 1 male (TET.34), coll. M. K. Tan & H. Yeo; NSSF main pond, 28 September 2013, 3 males (TET.37, 38, 43), 2 females (TET.42, 44), coll. M. K. Tan & H. Yeo; Upper Seletar Reservoir Park , 5 October 2013, 2 males (TET.55, 56), coll. M. K. Tan & H. Yeo ; Woodcutter trail, 11 October 2013, 1 male (TET.64), 1 female (TET.61), coll. M. K. Tan & H. Yeo ; NSSF main pond, 15 October 2013, 1 male (TET.76), 1 female (TET.80), coll. M. K. Tan & H. Yeo; NSSF interior, 23 October 2013, 3 males (TET.89, 91, 92), 1 female (TET.90), coll. M. K. Tan & H. Yeo; Upper Seletar Reservoir Park , 6 November 2013, 1 male (TET.100), 1 female (TET.101), coll. M. K. Tan & H. Yeo ; NSSF interior, 17 January 2014, 2 males (TET.105, 106), 1 female (TET.107), coll. M. K. Tan & H. Yeo; Woodcutter trail, 7 February 2014, 3 males (TET.116, 117, 118), coll. M. K. Tan & H. Yeo. Holotype and paratypes deposited in ZRC.

Diagnosis. New species is similar to Eucriotettix grandis , E. dohertyi , E. ridleyi , and E. simulans sp. nov. by lacking a long spine on lower side of the pronotal lobes. E. guentheri sp. nov. differs from E. grandis and E. dohertyi by narrow tegmen, the width of visible part of which is equal or slightly narrower than width of mid femur, while in both above mentioned species tegmen is distinctly broader than mid femur. The differences of this new species from Singaporean congeners are given in a key above.

Description. Male. Body of medium size for genus ( Figs. 5 A, 5C). Antennae filiform, 15-segmented; scapus 1.2 times as long as wide; mid segments (7–8th) 10–11 times as long as wide. Antennal socket situated distinctly above the lower margin of eyes ( Fig. 8 B). Eyes slightly elevated above the pronotum in lateral view ( Fig. 8 C). Lateral ocelli situated slightly above the middle of eyes. Fastigium of vertex with deep concavities behind lateral carinae, not produced in front of eyes in dorsal aspect, 1.3–1.4 times narrower than one eye seen from above; anterior margin of fastigium truncated, median carina of fastigium well defined; lateral carinae elevated; subocular lobes distinct ( Fig. 8 A). Frontal ridge in lateral view broadly triangularly rounded between the antennal sockets and weakly excised below the median ocellus; in frontal view the ridge narrow, its width between the bases of antennae 1.5 times less than the width of the 1st antennal segment ( Fig. 8 B). Pronotum finely nodulose near anterior half and more punctuated towards apical half; in dorsal view anterior margin of pronotum medially straight; posterior process of pronotum reaching two thirds of hind tibiae, process with truncated apex in dorsal view ( Figs. 5 A). Median carina of pronotum in profile low, slightly excised between shoulders; external lateral carina of pronotum almost straight; infrascapular area narrow ( Fig. 5 C). Lateral carina of pronotum in prozona well defined, parallel or converging posteriorly ( Fig. 8 A). Hind margin of lateral lobes of pronotum with deep tegminal sinus ( Fig. 8 C); lower side of the lateral lobes of pronotum forming triangularly pointed projection, the posterior margin of which almost straight ( Figs 5 A, 8A). Tegmina narrowly ovate; visible part of tegmen 2.7–2.9 times as long as wide and 1.1 times narrower or equal to width of mid femur. Hind wings slightly surpassing apex of the posterior process of pronotum. Fore and mid femora with almost straight and finely serrate lower and upper carinae. Fore femur 3.8–4.1 times, mid femur 3.8-4.5 times as long as wide. Hind femur slender, 3.4 times as long as wide; upper and lower carinae on the external side finely serrate; lower carinae on the inner side with a spine-like peg near the coxa. Dorsal side of hind tibia with 4–7 outer and 4–7 inner spines with minute denticles between spines. First tarsal segment of hind leg almost as long as 3rd segment (without claws); ventral side of the 1st segment with 3 triangular pads of the same shape. Epiproct narrow triangular, with pointed apex.

Abdomen. Epiproct narrow triangular, with pointed apex. Subgenital plate in lateral view short, shallow excised near pointed apex ( Fig. 8 D); apex of plate excised in ventral view ( Fig. 8 E). Cerci stout basally with pointed apex.

Colouration. Body brown to sometimes red brown, with few blackish and light brown patterns on pronotum and legs. Head brown, often with light brown stripes below eyes. Apical and 4th segments of maxillary palps white; 3rd segment sometimes white near the apical end. Antenna light brown basally, darken to brown or dark brown apically. Dorsal side and lateral lobe of pronotum brown to sometimes red brown, with few blackish and light brown patterns. Fore and mid femora brown or red brown with pale patterns. Fore and mid tibiae blackish, with three light rings. First segment of fore and mid tarsi brown, 2nd segment with whitish base and black apex; claws brown. Hind femur light brown or brown; ventrally black, with a narrow pale longitudinal band above the black ventral side. Hind tibiae dark brown, with blackish ring near the middle. First and second segments of hind tarsus brown, third segment with light brown base and blackish apex; claws brown. Abdomen in dorsal view blackish with two light brown longitudinal stripes.

Female. Similar to male, but larger ( Figs. 6 A, 6C). Scapus 1.2 times as long as wide; mid segments of antennae 7–8 times as long as wide. Fastigium of vertex 1.2–1.3 times narrower than one eye seen from above. Frontal ridge between the bases of antennae 2 times wider than the width of the 1st antennal segment. Width of visible part of tegmen equal to the width of mid femur. Fore femur 3.8–4.2 times, mid femur 4–4.3 times, hind femur 3.5 times as long as wide. Dorsal side of hind tibia with 5–7 outer and 4–6 inner spines.

Abdomen. Subgenital plate about as broad as long (shrunk in alcohol-preserved specimens); posterior margin of plate broadly rounded with indistinct median projection ( Fig. 8 G). Cerci with pointed apex. Valve of ovipositor narrow, dentate ( Fig. 8 F); length of the upper valve 4.8 times its maximum width; length of the lower valve 7.7 times its maximum width; apical tooth of lower valve strongly curved downward.

Colouration. Body, head and legs same as males. Abdomen generally dark brown to black, with some pale patterns on the lateral side of tergites (sometimes indistinct). Ovipositor light brown, with apices of denticles red brown.

Measurements (in mm). Length of body: male 7.2–8.2, female 7.1–9.1; pronotum: male 10.3–13.6, female 11.8–13.7; fore femur: male 1.5–2.0, female 1.5–2.1; mid femur: male 1.8–2.3, female 1.6–2.5; hind femur: male 5.3–5.8, female 5.9–6.4; ovipositor 1.1–1.6.

Distribution. Singapore.

Etymology. This species is dedicated to the Dr. Klaus Günther who made a great contribution to the taxonomy of Tetrigidae .

Figures

FIGURE 5. Habitus of male of Eucriotettix guentheri sp. nov. (TET. TET. 84) (A, C) and Eucriotettix simulans sp. nov. (TET. TET. 47) (B, D) in dorsal (A, B) and lateral (C, D) views. Scale bars = 1 mm.

FIGURE 6. Habitus of female of Eucriotettix guentheri sp. nov. (TET. TET. 42) (A, C) and Eucriotettix simulans sp. nov. (TET. TET. 113) (B, D) in dorsal (A, B) and lateral (C, D) views. Scale bars = 1 mm.

FIGURE 8. Eucriotettix guentheri sp. nov. (A – G) and Eucriotettix simulans sp. nov. (H – N): male head and anterior of pronotum in dorsal view (A, H); male face in frontal view (B, I); head, male pronotal lateral lobe and tegmen in lateral view (C, J); male (D, K) and female (F, M) abdominal apices in lateral view; male (E, L) and female (G, N) abdominal apices in ventral view. Scale bars = 1 mm.