Cuspidevia jaechi sp. nov. (Fig. 4 –6, 9–10, 14– 15) Type material. Holotype (IAECAS), male, CHINA: Jiangxi, Ganzhou City, Longnan County, Jiulianshan Natural Reserve, downstream of loc. 16, 10. X. 2009, leg. Bian & Tong (loc. 17). Paratypes (IAECAS): CHINA: 7 males, 13 females, the same data as holotype; 6 males, 15 females, Jiangxi, Yichun City, Jing’an County, Baofeng Town, 29 °00.307’N 115 ° 26.756 ’E, 132 m, 25. IX. 2009, leg. Bian & Tong (loc. 4); 2 males, 2 females, Jiangxi, Yichun City, Yifeng County, Guanshan Natural Reserve, 28 ° 33.022 ’N 114 ° 33.689 ’E, 376 m, 27. IX. 2009, leg. Bian & Tong (loc. 5); 1 male, 3 females, Jiangxi, Jinggangshan City, Ciping County, Dengjia Village, 26 ° 39.406 ’N 114 ° 14.597 ’E, 376 m, 29. IX. 2009, leg. Bian & Tong (loc. 6); 7 males, 5 females, Jiangxi, Ji’an City, Suichuan County, Caolin Town, 26 ° 15.851 ’N 114 ° 21.969 ’E, 208 m, 3. X. 2009, leg. Bian & Tong (loc. 11); 2 males, Jiangxi, Ganzhou City, Shangyou County, Wuzhifeng Town, 25 ° 57.420 ’N 114 °04.646’E, ca. 554 m, 5. X. 2009, leg. Bian & Tong (loc. 12); 3 males, Jiangxi, Ganzhou City, Shangyou County, Wuzhifeng Town, downstream of loc. 13, 7. X. 2009, leg. Bian & Tong (loc. 14); 1 male, Jiangxi, Ganzhou City, Shangyou County, ca. 1 km Northeast of Wuzhifeng Town, 7. X. 2009, leg. Bian & Tong (loc. 15); 4 males, 3 females, Jiangxi, Ganzhou City, Longnan County, Jiulianshan Natural Reserve, 24 ° 37.207 ’N 114 ° 32.114 ’E, 562 m, 9. X. 2009, leg. Bian & Tong (loc. 16). Diagnosis. This species is similar to Cuspidevia velaris and Cuspidevia brevis sp. nov. From the first it can by distinguished by 1) with three elytral striae well visible; 2) aedeagus having the ventral sac with more developed apical teeth. From the latter it can be recognized by 1) the first ventrite without carinae; 2) elytra with three striae well visible, not five; 3) elytral apices more distinctly produced; 4) aedeagus having the ventral sac with a pair of sharp apical teeth. Description. Body (Fig. 5) elongate, moderately convex; length 2.2–2.3 mm (pronotum and elytra), width 1.0– 1.05 mm. Colour dark brown to black; labrum, antennae and anterior margin of pronotum yellowishbrown. Head mostly retractable and hard to see from the dorsal view. Clypeus, frons and labrum covered with white adpressed pubescence. Pronotum a little wider than long, widest at basal third; lateral margin narrowly ridged; posterior angles acuminate, but not produced; anterior angles distinctly produced anteriad forming long acuminate spines; sublateral grooves on basal half (obsolete in some specimens); with a pair of granules in front of anterior angles of scutellum; disc with a short, shallow, median groove. Scutellum elongate triangular, without punctures. Elytra elongate, widest near middle; elytral apices densely granulate, distinctly produced, separately acuminate and curved laterally; first elytral stria (from hind margin of scutellum to middle) consisting of 11–13 punctures, separated by two or three diameters; second stria (from elytral 0.2 to 0.4) consisting of 7–8 punctures; third stria with 4–5 smaller punctures distinctly shorter than the second stria; intervals 1–6 flat and glabrous; seventh interval with a distinct granulated carina. Ventral view (Fig. 6). Prosternum distinctly produced anteriorly; lateral margin of prosternal process distinctly rimmed; middle of mesoventrite with a “V” shaped groove; metaventrite with a row of punctures along margin of mesocoxae, and median longitudinal suture shallowly impressed. Hind femora with some small golden setae at apical part; tibiae with cleaning fringes; claw without basal teeth. Abdomen with five ventrites; lateral sides with plastron; first ventrite without carinae; last ventrite long, and distinctly produced posterio-laterally. Aedeagus (figs. 9–10; 14–15), long and slender; penis about twice as long as phallobasis; ejaculatory duct distinctly sclerotized; ventral sac well-developed, with a pair of admedian, sclerotized teeth; parameres inconspicuous and fused to penis, and their apices with some setae. Females. Elytral apices less produced than males (Fig. 4). Distribution. China: Jiangxi. Habitat. Small stream, with stones, gravel, sand and decaying leaves. Etymology. This species is named for Dr. M. Jäch, a famous Coleopterologist.Published as part of Bian, Dongju & Ji, Lanzhu, 2010, Two new species of Cuspidevia Jäch & Boukal, 1995 from China (Coleoptera: Elmidae), pp. 53-58 in Zootaxa 2663 on pages 56-58, DOI: 10.5281/zenodo.27630