Psilotarsus brachypterus pubiventris (Semenov, 1900)

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 : 63-64

Psilotarsus brachypterus pubiventris (Semenov, 1900) Figs 1 D–F, 9G, H

Material examined.

Almaty Region: 28 km N of Kapchagay [ Қапшағай] (44°06'N, 77°03'E), 679 m a.s.l., 27 VI 2017, several females and many dead individuals on the road and the roadside, leg. LK, MW & WTS; 26 km N of Kapchagay [ Қапшағай] (44°06'N, 77°03'E), 648 m a.s.l., 27-28 VI 2017, 6♂♂, 20♀♀ (5♂♂, 7♀♀ - dead specimens), leg. LK; 2♂♂, 26♀♀, leg. MW; 1♂, 14♀♀, leg. WTS; 1♂ (dead specimen), 4♀♀, leg. MB; 22 km N of Kapchagay [ Қапшағай] (44°05'N, 77°02'E), 675 m a.s.l., 28 VI 2017, many dead individuals, leg. LK, MW & WTS.

Remarks.

This subspecies is distributed in the southeastern region of Kazakhstan (from the Chu-Ili Mountains to about Chilik and the Dzungarian Alatau) and northern Kyrgyzstan (from the environs of Kara-Balta to Bishkek) ( Danilevsky 2000).

It is characterised by larger, wider, robust body and relatively shorter antennae with shorter and thicker joint lobes ( Danilevsky 2000). The imagines can be active from the first half of May to the end of July ( Ishkov and Kadyrbekov 2004).

This taxon was observed at the end of June during warm (approx. 25 °C) weather conditions, after its mating period during which mostly females were still alive and the living males (Fig. 9G) constituted only a small percentage of the whole population. Also, among the females (Fig. 9H), many specimens (approx. 60%) were damaged or already dead including old body remains. Bite traces indicated that most of the specimens were killed or posthumously bitten by small mammals. In this area, any presence of Latrodectus tredecimguttatus , which seemed to be the main natural enemy of the aforementioned subspecies, were not observed. Moreover, many specimens that were killed by cars when attempting to pass or fly over the road were also found smashed on the asphalt or in the roadside vegetation strip. All three plots from which the beetles were collected are located within close proximity to each other and represent a temperate semi-shrub/dwarf semi-shrub desert habitat (Fig. 10A). It is worth noting that on 10 June (17 days earlier), insects had been being attracted to the light at a plot located only 2 km away from this location and that not even a single male was observed neither in the night nor in the morning of the next day. This may indeed indicate a rather short, approximately two-week-long, period of the occurrence of this subspecies, which would be in line with Danilevsky’s (2014a) findings.

It is also interesting to note that this subspecies seems to stay active for most of the day. Within two different plots, the females of P. b. pubiventris were observed from the late evening hours through most of the night (the last active specimens were found around 3-4 a.m.) as well as in the morning of the next day (around 9 a.m.). However, although most of the males were already dead, a few living specimens were caught only in the morning despite several hours of attempting to attract them to the light on the previous evening and night on the same plot. This unusual behaviour might be related to the end of the period of the occurrence and condition of the individuals. On the other hand, according to Danilevsky (2014a), there are contradictory observations concerning the activity of beetles. In 2001, the author collected numerous males only in the morning before the dawn (from 5 to 5:30 a.m) but with no females and no more males were caught earlier or later during the day or while attempting to attract them to a light source at night. A slightly different observation was made by S.V. Murzin in 1989 who noted the maximum activity of both sexes at the sunrise. However, according to Ishkov and Kadyrbekov (2004), there were signs of nocturnal activity.