Encyclops macilentus, a species occuring in oak forests of Russian Far East and Korea, has ben described as Microrhabdium macilentum from "East Siberia" by Gustav Kraatz in 1879 [▽].
E. macilentus is extremely rare taxon and is still represented only by a very small amount of specimens in all collections [✧]. The development is described in detail
by Alexei Cherepanov (1979)[❖]. Females lay eggs in bark crevices of viable oaks (Quercus) with diameter from 16 to 40 (or even more) cm at the human chest height. Larvae develop and pupate in cork
layer of the bark, often together with the larvae of Pidonia malthinoides. The adults, active from late May to June, lead a cryptic mode of life.
| Body length: | ♂♂ 6.0 - 7.0 mm / ♀♀ 6.5 - 8.0 mm |
| Life cycle: | 3 years |
| Adults in: | May - June |
| Host plant: | oak (Quercus spp.) |
| Distribution: | Russian Far East, Korea |
The depicted male beetle (7 mm) was collected at Kedrovaya (р. Кедровая) river bank
(N43°06′43″ E131°31′28″; 8 km SSE of Barabash, Khasansky district,
South of Primorsky krai, Far Eastern Federal District, Russia) on May 22-27, 2015.
Collected by Kirill V. Makarov
[▽]
Kraatz G.:
Ueber die mit der Bockkäfer-Gattung Xylosteus verwandten, zum Theil neuen Genera.
Deutsche entomologische Zeitschrift, Berlin 23 (1): 118, 1879.
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[✧]
Danilevsky M.L.:
Longicorn beetles (Coleoptera, Cerambycoidea) of Russia and adjacent countries. Part 1.
Higher School Consulting, Moscow, 550pp [page 69], 2014.
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[❖]
Cherepanov A.I.:
Cerambycidae of Northern Asia, Volume 1 - Prioninae, Disteniinae, Lepturinae, Aseminae.
Amerind Publishing, New Delhi: 304pp [pages 76-80], 1988.
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Miroshnikov A.I.:
Little known species of longicorn beetles (Coleoptera: Cerambycidae) from the Russian Far East / Малоизвестные виды жуков-дровосеков (Coleoptera: Cerambycidae) Дальнего Востока России.
Proceedings of the Russian Entomological Society, St. Petersburg 77: 226–234, 2006.
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