Stenothemus seediq, Hsiao, Yun, 2015

Hsiao, Yun, 2015, Description of two new species of the genus Stenothemus from Taiwan (Coleoptera: Cantharidae), Zootaxa 3937 (2), pp. 386-392 : 387-390

Stenothemus seediq sp. nov.

Figs. 2–3 , 6–9

Type material. Holotype ♂, Meifeng, 2100m, Jen-ai, Nantou, Taiwan, 23. XI. 2013, Y. Hsiao leg. ( NMNS). Paratypes: 2 ♂, 1 ♀, Meifeng, Central Cross-lsland Highway Wushe Branch 14.5K, Nantou Co., Taiwan, 2. XII. 2010, S.-W. Ho leg. ( NCHU); 16 ♂, same data as for the holotype (4 in NMNS; 6 in TARI; 3 in BMNH; 3 in YHC); 1 ♂, same locality, 23. XI-24. XII. 1997, C.-S. Lin & W.-T. Yang ( NMNS); 1 ♂, same locality, 4. XI-15. XII. 2003, C.-S. Lin & W.-T. Yang ( NMNS); 1 ♂, same locality, 15. XII. 2003 – 3. II. 2004, C.-S. Lin & W.-T. Yang ( NMNS).

Description. Male ( Fig. 2 ). Eyes black. Head and prothorax dark red to brown, pronotum with anterolateral parts and posterior margin yellowish brown. Antennae fuscous to brown, with basal part of each antennomere light yellow. Mandibles yellowish brown, with apices darker; maxillary and labial palpi yellowish brown. Coxae, trochanters and basal part of femora light brown; femora, apical parts of tibiae and tarsi fuscous to brown; tibiae, basal part of tarsi and claws yellowish brown. Elytra yellowish brown, disc with some round black spots. Body densely covered with fine yellowish pubescence; anterior margin of clypeus fringed with pale bristles; antennae, elytra and legs with some brownish bristles intermingled with primary pubescence.

Head as long as wide, eyes moderately protruding, ratio of an eye diameter to interocular space 1:2.85, dorsum slightly swollen on posterior part, depressed along the anterior margin of clypeus and in lateral areas before eyes; anterior margin of clypeus arcuate and slightly emarginated in middle; surface densely and finely punctate, each side with a rectangular impression behind antennal socket; antennae extending to apical third length of elytra, antennomere I clavate, II short and expanded apically, III to XI subcylindrical, ratio of the lengths of antennomeres I to XI as follows: 17:10:13.5:19:18:19:19:18:18:16:17.

Pronotum subquadrate, nearly as wide as head, about 0.96 times as long as wide; anterior margin almost straight; posterior margin arcuate, but feebly indented in middle; lateral margins feebly arcuate, constricted before posterior angles; anterior angles rounded; posterior angles slightly protruding and obtuse; disc swollen, with a pair of rounded elevations at posterolateral parts; antero-lateral areas hollowed; medio-longitudinal furrow distinct in central area; surface matt, finely and sparsely punctate. Scutellum triangular with rounded apex.

Elytra conjointly at maximal width about 1.7 times as wide as pronotum, about 2.7 times as long as wide, lateral margins subparallel at basal one-fifth, diverging posteriorly and widest at apical forth; surface densely and coarsely punctate, but fine and sparse anteriorly.

Prosternal process concave at the apex. Mesoventrite obviously convex along the middle line. Legs moderately slender; femora mostly straight; tibiae somewhat bent.

Aedeagus ( Figs. 6–8 ): ventral process of each paramere clavate and slightly bent inwards at apical part; dorsal plate of each paramere long-triangular, with the apex rounded, distinctly longer than ventral process, outer and inner lateral margins sinuate; each laterophyse bent dorsad with pointed apex, basal part of laterophyses globular and swollen.

Length: 5.5–7.5 mm (in the holotype: 7.0); width: 1.5–2.5 mm (2.0).

Female ( Fig. 3 ). Colour, punctation and pubescence resemble male. Body and pronotum obviously wider than that in male; head as long as wide, eyes less protruding than in male, ratio of an eye diameter to interocular space 1:2.90; antennae shorter than in male, extending to elytral midlength, ratio of the lengths of antennomeres I to XI as follows: 14.5:10:14.5:17.5:17:17:17.5:17.5:16:14.5:15.5. Pronotum about 1.10 times as wide as head, about 0.90 times as long as wide. Elytra conjointly about 1.8 times as wide as pronotum, about 2.4 times as long as wide.

Seventh abdominal ventrite ( Fig. 9 ): lateral and terminal parts densely pubescent, with posterior margin roundly emarginated, with a pair of horn-like processes in the middle.

Length: 7.3 mm; width: 2.3 mm.

Variation. In some paratypes, the spots on the elytra are indistinct.

Diagnosis. This new species is very similar to Stenothemus cou Hsiao , sp. nov., from which it differs by the slightly narrower interocular space, the structure of aedeagus, especially the long-triangular dorsal plate and the shape of laterophyses, and the pair of horn-like processes in middle of the female seventh abdominal ventrite.

Biological notes. Up to now, this new species has only been collected in the type locality, Meifeng, located in the central area of Taiwan. The altitude of their habitat is about 2,100 meters and they appear mainly in winter according to the label data. Stenothemus seediq is sympatric with S. wittmeri , S. taiwanus and S. owadai , however, S. wittmeri appears mainly in August to September. In addition, S. seediq exhibits phototaxis at night and is readily attracted to the light of a mercury lamp.

Etymology. The specific name is given in honor of the Seediq Taiwan Indigenous People who live in central Taiwan, especially in Jen-ai Township, which is the type locality of this new species.

Distribution. Central Taiwan (endemic).

Figures

FIGURES 2 – 5. Habitus, dorsal view: 2 – 3. Stenothemus seediq sp. nov.; 4 – 5. S. cou sp. nov. 2, 4. male holotypes; 3, 5. female paratypes (photographed by Mr. Ming Liu). Scale bars = 5.0 mm.

FIGURES 6 – 9. Stenothemus seediq sp. nov. 6 – 8. Aedeagus (6. ventral view; 7. lateral view; 8. dorsal view); 9. Seventh abdominal ventrite of female, ventral view. Scale bars = 0.5 mm.