Aspidaphaenops xiongda, Tian & Huang, 2018

Tian, Mingyi & Huang, Sunbin, 2018, Contribution to the knowledge of the cavernicolous beetle genus Aspidaphaenops Uéno from Guizhou (Coleoptera: Carabidae: Trechinae), Zootaxa 4422 (2), pp. 244-258 : 247-253

Aspidaphaenops xiongda n. sp.

Figs. 1d , 2E , 4C, D , 6, 7A , 8 , 9

Material. Holotype male, Fengyan Dong, Renjia Zhai, Longguang , Anlong , Qianxinan , Guizhou, 25°10’05.65’’ N / 105 ° 13 ’50.69’’ E, 1436 m, 12-V- 2017, Mingyi Tian, Weixin Liu, Xiaozhu Luo, Pingjing Yang & Yanyi Pu leg., in SCAU ; paratypes: 5 males, ibid, in SCAU .

Length: 7.3–7.5 mm; width: 1.9–2.0 mm. Habitus as in Fig. 6.

Body yellowish brown to brown, but pale on mouthparts palps, tarsi and antennomeres 9–11; moderately shiny and whole body including abdominal ventrites glabrous, legs pubescent; microsculptural engraved meshes strongly transverse on head, pronotum and elytra; fore body (with mandibles) slightly longer than elytra, (HmL+PrL) / EL = 1.07–1.10, or shorter (excluding mandibles), (HlL+PrL) / EL = 0.90–0.91.

Head elongated quadrate, much longer than wide, HLm/HW = 2.24–2.30, HLl/HW = 1.71–1.74; widest just behind sockets of antennae, at about 1/3 of head from labrum, genae gently and straightly narrowed posteriad, not parallel-sided; frons and vertex moderately convex, frontal furrows well-marked, deep and distinctly divergent posteriad, ended just behind middle head from labrum; clypeus transverse, quadrisetose; labrum transverse, frontal margin slightly emarginated, 6-setose; anterior and posterior frontal setiferous pores at apical 1/3 and basal 1/3 of head from labrum and clypeus respectively; mentum and submentum completely fused, mentum bisetose on either side of tooth which is simple and blunt at apex, basal fovea widely concave; submentum 11 to 12-setose; both maxillary and labial palps thin and subcylindrical, glabrous except for the 2nd labial palpomere which is bisetose on inner margin and one or two additional setae on outer margin; the 2nd labial palpomere nearly 1.4 times as long as 3rd; the 3rd maxillary palpomere nearly 1.3 times as long as 4th; suborbital pore closer to base of head than to submentum. Antennae thin and long, extending over apices of elytra.

Prothorax not dilated, propleura invisible from above. Pronotum campanulate, longer than wide, PnL/PnW = 1.20–1.22, widest at about 1/3 of pronotum from base, recurved before hind angles which are not well-defined, fore angles protruded though obtuse; base as wide as front; latero-margins strongly widened and reflexed near base, fore latero-marginal setae at about apical 1/4 of pronotum. Scutellum fairly large.

Elytra ovate ( Fig. 7A ), much longer than wide, EL/EW = 1.43–1.45; twice as wide as pronotum; widest near the middle, prehumeral borders strongly serrate, marginal gutters well-marked; punctures of striae isolated one another; sites of anterior dorsal pores variable, at the portions about 1/4 of elytra from base; middle pores at about middle of elytra; preapical pores much closer to elytral suture than to elytral apices; the 1st to 3rd pores of the marginal umbilicate series not equidistant, 2nd pore closer to 3rd than to 1st; distance between the 4th and 3rd subequal to that between 1 st and second, 5th and 6th pores close to each other.

Legs thin and long, bearing short pubescence; fore tibia smooth, presence of a faint longitudinal furrow or sulcus; the 1 st tarsomere , shorter, as long as and slightly longer than 2nd –4th tarsomeres together in fore, middle and hind legs, respectively.

Ventrites IV–VI each with a pair of paramedian setae; ventrite VII bisetose in male

Male genitalia ( Figs. 4C, D ): Moderately sclerotized, thin and slender, more elongate than in A. reflexus , almost rectangularly arcuate ventrally at about basal 1/4, apical lobe shorter than in A. reflexus , strongly recurved and reflexed at apex; base wide, sagittal aileron large and thick; inner sac of the median lobe with an anisotopic and short copulatory piece which is about 1/6 as long as the median lobe; in dorsal view, apex more or less tube-like, thin and nearly parallel-sided, broad at apex which is reflexed; parameres well-developed but much thinner than in A. reflexus , about 1/3 as long as median lobe, each with three long apical setae.

Female: Unknown.

Remarks. Similar to Aspidaphaenops reflexus Uéno, 2006 , but differs from it by: (1) head gradually narrowed posteriad, instead of nearly parallel-sided in A. reflexus ; (2) fore angles of pronotum strongly protruded (vs. hardly protruded in A. reflexus ); (3) hind lobes of pronotum more reflexed; and (4) fore latero-marginal setae at about frontal 1/4 of pronotum, instead of 1/ 5 in A. reflexus .

Etymology. “Xiongda” is a nickname of Dr. Philip John Rowsell, a famous British speleologist (Hong Meigui Cave Exploration Society), to thank his valuable support to our field trip in Xingyi.

Distribution. Guizhou (Anlong). Known only from cave Fengyan Dong ( Figs. 1d , 8 ).

Fengyan Dong opens at the right side of a road to the village Renjia Zhai, with a large entrance and a small stream throughout the main passage ( Figs. 9A, B ). It is about 1100 m long, with two branches at both sides of the main passage. Both are longer than the main passage. There are several small portions which are muddy and moist enough and good for cave beetles ( Figs. 9C, D ). This new species is sympatric with another trechine beetle Trechiotes sp., millipedes, pseudoscorpions, spiders and springtails.

Figures

FIGURE 1. Distribution of Aspidaphaenops species (a. A. dudou n. sp.; b. A. volatidraconis; c. A. masakii; d. A. xiongda n. sp.; e. A. reflexus).

FIGURE 2. Heads of Aspidaphaenops species, dorsal view (A. A. masakii; B. A. volatidraconis; C. A. dudou n. sp.; D. A. reflexus; E. A. xiongda n. sp.).

FIGURE 4. Male genitalia of Aspidaphaenops species, median lobe and parameres (lateral view), and apex (dorsal view) (A, B. A. reflexus; C, D. A. xiongda n. sp. holotype).

FIGURE 7. Left elytron of Aspidaphaenops species (A. A. xiongda n. sp.; B. A. dudou n. sp.).

FIGURE 8. Map of cave Fengyan Dong, type locality of Aspidaphaenops xiongda n. sp. (courtesy of Dr. Philip John Rowsell, Hong Meigui Cave Exploration Society, triangles indicating where the beetles were collected).

FIGURE 9. Cave Fengyan Dong, type locality of Aspidaphaenops xiongda n. sp. (A. entrance; B. main passage; C, D. active beetles in the cave).Prothorax not dilated, propleura invisible from above. Pronotum barrel-like, longer than wide, PnL/PnW = 1.19–1.20, widest near the middle of pronotum, strongly recurved before hind angles which are not well-defined, fore angles obtuse; base as wide as front; latero-margins gradually widened and reflexed from middle to base, fore latero-marginal setae at about 1/5 anterior of pronotum. Scutellum fairly large.