Octomeristes minutissimus ( Lesne, 1932 ) Liu, Lan-Yu, Beaver, Roger A. & Sanguansub, Sunisa, 2016

Liu, Lan-Yu, Beaver, Roger A. & Sanguansub, Sunisa, 2016, A new Oriental genus of bostrichid beetle (Coleoptera: Bostrichidae: Xyloperthini), a new synonym and a lectotype designation for Octodesmus episternalis (Lesne, 1901), European Journal of Taxonomy 189 (189), pp. 1-12 : 9-10

Octomeristes minutissimus ( Lesne, 1932) comb. nov.

Octodesmus minutissimus Lesne, 1932: 662 .

Although Lesne (1932) deposited syntypes of Octodesmus minutissimus Lesne in MNHN, they can no longer be found (LYL, pers. obs. 2008; A. Taghavian, pers. comm. 2013). The remaining syntypes were deposited at the Forest Research Institute, Dehra Dun in India ( Lesne 1932), and are unavailable for study. Specimens of this species could not be located in any of the fifteen major European museums visited by LYL, and none are in the large collection of M. Ivie (pers. comm. 2013). We have been unable to borrow specimens from India, the only country in which the species has been collected. However, we have been able to examine photographs of three specimens of Od. minutissimus in the National Pusa collection of the Indian Agricultural Research Institute, New Delhi. Unfortunately, the antennae of these specimens were missing or damaged, and we have no photograph of the ventral side of a female. However, we have been able to check other characters against the original description of Lesne (1932), and the redescription and figure of Rai (1971). It should be noted that there are some discrepancies between Rai’s (1971) and Lesne’s (1932) descriptions. In particular, Rai (1971) does not mention or figure the emarginations of the elytral declivity described by Lesne (1932), nor does he mention the modifications of the female abdomen, nor the lateral pieces of the fifth abdominal ventrite of the male. The reasons for this are unknown. We believe that Lesne’s (1932) original description is correct with regard to all these characters.

Following Lesne’s (1932) description, the species possesses the antennal characters of Octomeristes gen. nov. rather than those of Octodesmus ( Table 1 ), and the characters of the male and female abdomen are those of Octomeristes gen. nov. The sculpture of the elytral declivity with a pair of costae on the upper margin is closer to that of Om. pusillus gen. et sp. nov., than to the large declivital spines found in Od. episternalis and Od. parvulus . Accordingly, we here transfer Od. minutissimus Lesne from Octodesmus to Octomeristes gen. nov.

Octomeristes minutissimus comb. nov. can be distinguished from Om. pusillus gen. et sp. nov. by the presence of two costae on each elytron and not three, and in the female by the presence of two long and thin spines in the middle of the posterior margin of the 4 th ventrite ( Lesne 1932). The spines are much smaller and normally concealed by the 3 rd ventrite in the female of Om. pusillus gen. et sp. nov.

Additional nomenclatural notes