Crossotarsus brevis (Browne, 1975) Lai & Zhang & Li & Wang, 2021

Lai, Shengchang, Zhang, Ling, Li, You & Wang, Jianguo, 2021, A new species, a new combination, and a new record of Crossotarsus Chapuis, 1865 (Coleoptera, Curculionidae, Platypodinae) from China, ZooKeys 1028, pp. 69-83 : 69

Crossotarsus brevis (Browne, 1975) comb. nov. Figures 3 , 4

Platypus brevis Browne: Beaver and Browne 1975: 306.

Dinoplatypus brevis Browne: Beaver 1998:184.

Material examined.

7 males, 5 females (JXAU); 1 male, 1 female (RAB): China: Yunnan Province, Xishuangbanna Dai Autonomous Prefecture, Jinghong City, Damanmi Village , 22°02'50"N, 100°48'27"E, ca 580 m, 20.I.2018, log dissection, host unknown, Shengchang Lai leg.

Taxonomy.

The specimens in the RAB were identified by comparison to a paratype C. brevis , which is also in the RAB. Browne put this species in Platypus Herbst, noting that the apical emargination of the elytra was rather similar to that of Platypus caliculus Chapuis 1865 ( Beaver and Browne 1975). In fact, C. brevis has the typical characters of Crossotarsus : labial palps two-segmented, with basal segments fused in the midline, whereas Platypus has the labial palps three-segmented, with separate basal segments. Beaver (1998) transferred the species from Platypus to Dinoplatypus Wood following Wood’s (1993) attempt to split the genus Platypus . Wood diagnosed Dinoplatypus largely on the basis of the circular, truncate, elytral declivity of the male, with the sutural apex emarginate. However, this is an adaptive character of the declivity which has evolved independently more than once in the Platypodinae , as it has in the Scolytinae ( Hulcr et al. 2015). Molecular phylogenetic study also shows that the few morphological characters used by Wood (1993) to erect several groups of Neotropical and Indo-Malayan/Australasian species in Platypodini to new genera are not sufficiently diagnosable for all those groups ( Jordal 2015).

Browne (1961) and Beaver and Sanguansub (2015) suggested that the adult generic characters of primary value in Crossotarsus included the structure of the labial and maxillary palps, the form of the pronotum, the sexual dimorphism of the protibia, and various modifications of the abdominal sternites in the male. Based on the two-segmented labial palps, the lateral pronotal emarginations angulate anteriorly, the pronotum without mycangial pores, and the sexual dimorphism of the protibiae, Platypus brevis belongs in the genus Crossotarsus , and is here transferred to that genus.

Distribution.

Thailand ( Beaver and Liu 2013). New to China (Yunnan).

Host.

Castanopsis sp. ( Fagaceae ) ( Beaver and Liu 2013).

Figures

Figure 3. Male of Crossotarsus brevis (Browne) A dorsal view B head C lateral view D declivity. Scale bars: 0.5 mm.

Figure 4. Female of Crossotarsus brevis (Browne) A dorsal view B head C lateral view D declivity. Scale bars: 0.5 mm.