Genyocerus talurae (Stebbing)

Beaver, R. A. & L. - Y, 2007, A review of the genus Genyocerus Motschulsky (Coleoptera: Curculionidae: Platypodinae), with new synonyms and keys to species, Zootaxa 1576 (1), pp. 25-56 : 41

Genyocerus talurae (Stebbing)

(Figs 35–36)

Diapus talurae Stebbing, 1906: 418 .

Genyocerus talurae (Stebbing) . Wood & Bright, 1992: 1096.

Diapus furtivus Sampson, 1913: 450 . Synonymy: Beeson, 1921: 22.

Diapus mirus Sampson, 1913: 452 . Synonymy: Sampson in Stebbing, 1914: 633.

Genyocerus dipterocarpi Browne, 1977: 98 . n. syn.

Taxonomy: We have compared male and female paratypes of G. dipterocarpi (BMNH) with specimens in RAB's collection that had earlier been compared with syntypes of D. furtivus (BMNH) . The synonymy of D. furtivus with G.talurae , suggested by Beeson (1921), was confirmed by Wood after examination of type material ( Wood & Bright 1992). The synonymy of D. mirus with D. furtivus was already suggested by Sampson in a personal communication to Stebbing (1914) and has been noted by Schedl (1972a) and Wood & Bright (1992). Apart from a small difference in size (3.1–3.4 mm length for G. dipterocarpi , 3.5–3.7 mm for G.talurae ), the only real difference between the males of the two species is the smaller number of mycangial pores on the pronotum of G. dipterocarpi (one or rarely two pores per side in G. dipterocarpi , three to five pores per side in G. talurae ). As noted above, the number of pronotal pores can be quite variable and must be used with caution as a character at specific level. The females of G. dipterocarpi are smaller (3.1–3.2 mm long, excluding the hair brushes, and the part of the abdomen extending beyond the elytra, relative to 3.5–3.6 mm for G. talurae ), but otherwise agree. G. talurae ranges from India to Vietnam, whereas G. dipterocarpi is known only from the Andaman Islands. However, in the absence of any information on genetic distinctiveness, we do not believe that G. dipterocarpi is morphologically sufficiently distinct to be given subspecific rank.

Distribution: India (including Andaman Is.), Myanmar, Pakistan, Thailand, Vietnam. It has been intercepted in timber imported to Japan from East Malaysia (Sabah, Sarawak) ( Browne 1986, Ohno 1990b) and Indonesia (Sumatera) ( Ohno et al. 1986), but its presence in these countries should be confirmed.

Biology: Recorded from the following genera of Dipterocarpaceae : Anisoptera , Dipterocarpus , Shorea , Vateria , Vatica . Other recorded hosts are: Canarium euphyllum (Burseraceae) , Lannea coromandelica (= Odina wodier ) ( Anacardiaceae ) and Quercus semicarpifolia (Fagaceae) ( Browne 1977, Wood & Bright 1992). It is unlikely that the three latter species are regular hosts. The life history, gallery system and economic importance of the species are described by Beeson (1917, 1961). Of particular interest is the observa- tion by Beeson (1917) that the male secretes wax from minute pores on the posterior part of the elytra. This wax is used to form a short tube at the entrance to the gallery system.