Eucriotettix simulans 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 : 390-391

Eucriotettix simulans Tan & Storozhenko , sp. nov.

Material examined. Holotype—male, Singapore: NSSF main pond, 28 September 2013, coll. M. K. Tan & H. Yeo (TET.47). Paratypes: 2 males (TET.48, 50) same data as holotype ; 1 male (TET.82), same locality, 15 October 2013, coll. M. K. Tan & H. Yeo ; 2 females (TET.111, 113), same locality, 26 January 2014, coll. M. K. Tan & H. Yeo. Holotype and paratypes deposited in ZRC.

Diagnosis. New species is similar to Eucriotettix guentheri sp. nov. but easily distinguished by the shape of projection on the lower side of the lateral lobes of pronotum ( Fig. 8 H vs Fig. 8 A) and by the female subgenital plate ( Fig. 8 N vs Fig. 8 G). The differences of a new species from E. ridleyi are given in a key. E. simulans sp. nov. is most similar to E. dohertyi in the shape of lateral lobes of pronotum but differs by hind wings exceeding apex of posterior pronotal process and by narrow tegmen (in E. dohertyi hind wings only reaching the apex of posterior process of pronotum and tegmen distinctly broader than mid femur).

Description. Male. Body of medium size for genus ( Figs. 5 B, 5D). Antennae filiform, 15-segmented; scapus 1.3 times as long as wide; mid segments (7–8th) 9–10 times as long as wide. Antennal socket situated between the lower margins of eyes ( Fig. 8 I). Eyes slightly elevated above the pronotum in lateral view ( Fig. 8 J). Lateral ocelli situated slightly above the middle of eyes ( Fig. 8 I). Fastigium of vertex with deep concavities behind lateral carinae, not produced in front of eyes in dorsal aspect, 1.2 times narrower than one eye seen from above; anterior margin of fastigium truncated, median carina of fastigium produced in front of anterior margin of fastigium; lateral carinae elevated; subocular lobes distinct ( Fig. 8 H). Frontal ridge in lateral view broadly rounded between the antennal sockets and weakly excised below the median ocellus; in frontal view the ridge broadened, its width between the bases of antennae almost equal to the width of the 1st antennal segment ( Fig. 8 I). Anterior half of pronotum finely nodulose, apical part more punctuated; in dorsal view anterior margin of pronotum straight; posterior process of pronotum reaching two thirds of hind tibiae, in dorsal view the apex of process truncated ( Fig. 5 B). Median carina of pronotum in profile low, slightly raised above tegmen; external lateral carina of pronotum almost straight; infrascapular area narrow ( Fig. 5 D). Lateral carina of pronotum in prozona well defined, parallel or converging posteriorly ( Fig. 8 H). Hind margin of lateral lobes of pronotum with deep tegminal sinus ( Fig. 8 J); lower side of the lateral lobes of pronotum forming triangular projection, the posterior margin of which excised ( Figs 5 B, 8H). Tegmen elongated oval with apical margin rounded; visible part of tegmen 2.7–2.8 times as long as wide and its width equal to width of mid femur. Hind wing long, slightly surpassing apex of pronotum. Fore and mid femora with almost straight and finely serrate lower and upper carinae. Fore femur 4.2 times, mid femur 3.6 times as long as wide. Hind femur slender, 3.7–3.8 times as long as wide; upper and lower carina on the external side finely serrated; lower carina on the inner side with a spine-like peg near the coxa. Upper side of hind tibia with 5–6 outer and 5–6 inner spines and with minute denticles between spines. First tarsal segment of hind leg as long as 3rd segment (without claws); ventral side of the 1st segment with 3 triangular pads of the same shape.

Abdomen. Epiproct narrow triangular, with pointed apex. Subgenital plate in lateral view deeply excised near pointed apex ( Fig. 8 K); in ventral view the apex of plate excised ( Fig. 8 L). Cerci conical with pointed apex.

Colouration. Body brown, 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 second apical segments of maxillary palps white; third apical segment sometimes white near the apical end. Antenna light brown basally, darken to brown or dark brown apically. Dorsal side and lateral lobes 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, second 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 tibia 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 from above blackish with two light brown longitudinal stripes.

Female. Similar to male, but larger ( Figs. 6 B, 6D). Scapus 1.2 times as long as wide; mid segments of antennae 7–8 times as long as wide. Fastigium of vertex 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 4 times, mid femur 4.3 times, hind femur 3.6–3.8 times as long as wide. Dorsal side of hind tibia with 6–7 outer and 6 inner spines.

Abdomen. Subgenital plate about as broad as long (shrunk in alcohol-preserved specimen); posterior margin of plate straight with distinct median projection ( Fig. 8 N). Cerci conical. Valve of ovipositor narrow, dentate ( Fig. 8 M); length of the upper valve 3.5 times its maximum width; length of the lower valve 7.3 times its maximum width; apical tooth of lower valve strongly curved downward.

Colouration. Body, head and legs same as male. 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 6.8–8.4, female 8.2–8.5; pronotum: male 11.3–11.9, female 12.6–13.0; fore femur: male 1.7–2.0, female 2.1; mid femur: male 2.0–2.1, female 2.3; hind femur: male 5.4–5.7, female 6.4–6.5; ovipositor 1.2–1.4.

Distribution. Singapore.

Etymology. This species name refers to the morphological similarities between this species and Singaporean congeners and derived from the Latin word simulans (= imitating).

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.