Alulatettix angustivertex n. sp. is described with illustrations of external morphology and female genitalia in detail. Comparison between the species A. angustivertex n. sp. and the other species of the genus Alulatettix is compiled into a table for identification. The distribution map of this species in Taiwan and its offshore islands is also provided.
Alulatettix Liang 1993 is a small genus of Tetrigidae. There are 3 species of this genus that have been found in China, i.e., A. yunnanensis Liang, 1993, from Yunnan, A. wudanshanensis Wang & Zheng, 1997, from Hubei, and A. zhengi Niu, 1994, from Henan. Some species from Japan (Ichikawa, 1993), some from Guangxi have been published (Jiang & Zheng, 1998), and 2 species from Hubei (Zhong & Zheng, 2003) as members of the genus. The only revision of the genus is by Zheng and Zhong (2001). The genus Alulatettix is recorded here for the first time in Taiwan.
Alulatettix angustivertex, n. sp. (Figs 1–12)
General Coloration.— General color brown. Posterior part of vertex with pair of black spots posteriorly. Eyes dark brown. Tip of each antennal segment ringed with yellow, and tip of last segment white. Middle femur dark-brown upper margin with 2 white marks, paginal area with 5 irregular yellow spots, arranged in line medially, lower margin area with rectangular brown spots at base. Hind femur brown, upper margin area with 2 small dark-brown bands, paginal area dark brown at base; lower margin area dark brown; apex of hind femur dark brown. Hind tarsi with 1st one light brown, apical 2 brown.
External morphology.— ♂:vertex narrow, protruding indistinctly over the eyes, anterior margin bordered with carinae, the middle and lateral ones distinctly connected; middle carina running into frons anteriorly, lateral and middle carinae connected and bordering anterior margin of vertex distinctly; all carinae extending posteriorly to 1/3 width of eyes; area between carinae forming a concave fossa. Vertex about 1.1 × as wide as eye. Head in lateral view with frontal carinae strongly curved inward at level of eyes, slightly protruding at level of antennae. Longitudinal groove of frontal fossae narrower than diameter of antennal socket. Lateral ocelli situated right at middle, in front of the eyes. Antennae filiform, 15-segmented, situated at inner sides of ventral margin of the eyes, the length of the 8th segment [=middle segment of Liang (1993) ] about 5 × its width. Pronotum tectiform, dorsal margin arched in profile; anterior margin straight. Length of prozona about 1.3 × its width. Pronotal process reaching posterior end of abdomen, apex of process incised triangularly at middle. Two short carinae on the protuberance at the anterior third of the pronotum; posterior margin of lateral lobes in lateral view with 2 sinuses, the first extremely shallow; posterior angles of lateral lobes rounded at apex. Forewing small, elliptic, invisible, covered by pronotum, about 2.5 × longer than broad; Hindwings strongly reduced as strips, about 3.3 × longer than broad, in lateral view slightly exposed by the pronotum. Middle femur oblong stout, about 2.5 × longer than broad, dorsal margin irregularly dentate, ventral margin sinuate, bordered with denticules. Hind femur club-like, about 2.5 × longer than broad; hind femur about 3 × wider than the middle femur; hind femur with both antegenicular and genicular denticles sharp; apex of lower marginal area round; dorsal margin dentate on apical third; ventral margin dentate on apical half. First segment of hind tarsi about 1.4 × longer than the 2ndand 3rd segments together. Pulvilli of 1st tarsal segment nearly triangular, tip sharp in profile, the first 2 pulvilli smaller than the 3rd one.
Female: Size in females slightly larger than in males, about 1.1: 1. Vertex about 1.2 × wider than the eye.
Female genitalia: Ovipositor valves thick and stout, surface smooth, each with 7 denticles at dorsal and ventral margin, about 3 × longer than broad. Subgenital plate subquadrate, narrower than long, about 1:1.3, posterior margin produced at the middle, triangular.
Measurements.— Data shown in Table 1.
Holotype.— ♂ (1454-6), Taiwan: Taitung county: Orchid Island: Hontou: fields nearby Dragon-head Rock (Longtouyen) (long 121°35′16.116′′E, lat 22°00′58.449′′N) 29.viii.2001, Coll. M. Y. Tsai. (Deposited at Department of Entomology, National Chung Hsing University, Taichung, Taiwan).
Paratypes.— 1 ♂ (1373-01), Taiwan: Nantou county: Chushan: Wire pole (Linding GauhFen# 187) (long 120 40′ 46.710′′E/ lat 23 38′51. 634 N), 22.iv.2001, Coll. M. Y. Tsai. 1♀ (1278-32), Taiwan: Kaohsiung county: Tengchih: forest road 400m beyond TESRI Experimental Station at middle-altitude (lat 23 04′31.266′′N, long 120 45′03.009′′E) 5.vii.2000, Coll. M. Y. Tsai. 4 ♀ ♀ (1487-01, 1487-02, 1487-03, 1487-04), Taiwan: Pingtung county: Lilongshan walking path (lat 23 01′50.032′′N, long 121 08′38.994′′E), 21-viii-2001, Coll.
J. H. Chen. 1 ♂ (1358-23), Taiwan: Pingtung county: Nanjenshan (lat 22 04′58.806′′N, long 120 49′51.860′′E), 09.ii.2001, Coll. J. H. Chen. 1 ♂ (1453-02), Taiwan: Taitung county: Orchid island: small path to Tein-Chih, in front of Chungai-Chiao bridge about 400m (lat 22 00′28.965′′N, long 121 34′23.657′′E), 29.viii.2001, Coll. M. Y. Tsai. 1 ♀ (1316-09), Taiwan: Taitung county: Taitung county road #23 4.5K (lat 22 58′ 41.399′′N, long 121 15′06.334′′E), 21.vii.2000, Coll. M. Y. Tsai.
Distribution.— Taiwan (Fig. 13).
Etymology.— From the latin, Angustus, meaning ′narrow′, in reference to the narrow vertex.
Diagnosis.— Features permitting dicrimination among species of Alulatettix and diagnosis of A. angustivertex are presented in Table 2.
Remarks: The new species is most similar to Alulatettix wudangshanensis, but is easily distinguished by morphological characters of the males as shown in Table 2.
We are much indebted to Dr. G. Q. Liang, Institute of Entomology, Sun Yat-Sen University, Guanchou, China, Dr. A. Ichikawa and Mr. A. Dubitzky, Zoologischen Staatssammlung, München for sending valuable material. We thank Mr. Jeng-Hsiung Chen at the National Museum of Natural Science, Taichung, Taiwan for helping in many ways while collecting in the field. Financial support through the National Science Council, Taiwan, R. O. C. (NSC 89-2313-B-005-102, NSC 90-2313-B-005-145 and NSC 92-2621-B005-001) is much appreciated by the authors.