Algon tibetanus species group Diagnosis. The species group can be defined by the combination of following characters: Head and pronotum with fine microsculpture (type II) (Fig. 3, 4); basal depression and punctural grooves of elytra with iso-diametrical microsculpture (type IIIa), surface between grooves glossy; bases of abdominal tergites with microsculpture (type IIIa); posterior margin of tergite VII with whitish seam; aedeagal paramere with medio-longitudinal elevation dorsally (toward median lobe), lateral extension not developed. The species group is endemic to Xizang, China. Couplet # 6 in the key to species groups of Algon (Schillhammer 2006: 140) should be modified as follows to accommodate the Algon tibetanus species group: 6 Elytra almost impunctate, densely micro reticulate, with rows of larger punctures............... uniformis species group - Elytra densely punctate, without rows of larger punctures.................................................... 6a 6a Elytra with iso-diametrical microsculpture only in basal depression and punctural grooves of elytra...................................................................................................... tibetanus species group - Elytra without micro-reticulation, or with micro-reticulation on entire surface.................... species incertae sedis

Published as part of Li, Chong & Tang, Liang, 2023, New species and records of Algonina Schillhammer & Brunke, 2018, mainly from China, pp. 457-482 in Zootaxa 5256 (5) on page 466, DOI: 10.11646/zootaxa.5256.5.3, http://zenodo.org/record/7758930