Xylotrechus capricornus (Gebler, 1830)

Karpinski, Lech, Szczepanski, Wojciech T., lewa, Radoslaw, Walczak, Marcin, Hilszczanski, Jacek, Kruszelnicki, Lech, Los, Krzysztof, Jaworski, Tomasz, Marek Bidas, & Tarwacki, Grzegorz, 2018, New data on the distribution, biology and ecology of the longhorn beetles from the area of South and East Kazakhstan (Coleoptera, Cerambycidae), ZooKeys 805, pp. 59-126 : 74-75

Xylotrechus capricornus (Gebler, 1830) Fig. 2K, L

Material examined.

East Kazakhstan Region: Bykovo [ Быково] env. (49°39'N, 84°33'E), 570 m a.s.l., 21 VI 2017, 1♂, 1♀, leg. LK.

Remarks.

Xylotrechus capricornus is a rare species that is distributed from Central Europe (Austria and the Czech Republic) to West Siberia ( Sláma and Gutowski 1997, Danilevsky 2018a). It is probably monophagous on birch Betula spp. The females are very exacting in regard to the required health condition of a host plant. Although trees are occupied infrequently, many of them, especially those that are completely exposed, can be totally inhabited by numerous specimens on almost the entire surface of a trunk. The larvae first feed under the bark and then in the wood of trunks that have recently died. Pupation occurs deep in the wood. The life cycle of this species usually lasts two years, but can be extended up to three years. A situation in which two generations develop in the same host is very unusual. While the adults are active from the end of June to mid-August, imagines are rarely observed in nature - the beetles appear only on the hottest days and they usually disappear immediately after the sun sets behind the clouds or when the weather becomes windy or cold. Only a small part of a whole population can be spotted outside of the wood ( Sláma and Gutowski 1997).

Until recently, the species was known from Kazakhstan only based on a single specimen that was found near Karkaralinsk ( Kostin 1973). Then, in June 2005, several specimens were collected on birch bark in the Putintsevo environs by Danilevskaya et al. (2009). That was the first record in NE Kazakhstan.

In our research, a pair of X. capricornus was collected at the edge of a mountain deciduous grove that consisted mainly of Populus , Betula and Salix (Fig. 15C). Around noon, during hot weather, the beetles were copulating on birch trunks that were lying on a sun-exposed site. Our finding confirms the presence of this species in Kazakhstan.