According to Rejzek & Vlasák (2000) Necydalis major develops
in a variety of deciduous trees preferring Tilia, Quercus, Salix, Populus,
but mainly Alnus. In contrast to Necydalis ulmi this
species develops in dead trunks and branches of larger diameter. It never develops in hollows of
living trees. Surprisingly, from a dead trunk of Alnus glutinosa attacked by larvae of
N. major the polypore Inonotus radiatus was isolated. Larvae of N. major seem to
prefer a rusty-brown substrate just under the fruitbodies of I. radiatus but were also found
in more decayed parts of the trunk, in a white substrate. Sometimes, analogously to N. ulmi,
the larval galleries were surrounded by a rusty-brown mycelar circle well visible especially when the
galleries were built in the white substrate. On the other hand, larvae of N. major were also
found in highly decayed trunks of Tilia, Quercus, Ulmus, and Salix with
no trace of any Inonotus species presence. Therefore, it can be concluded that the substrate
requirements of N. major are much less strict than in case of N. ulmi. This observation
correlates with the fact that N. major is a much more frequent species in nature than N. ulmi.
|Body length:||19 - 32 mm|
|Life cycle:||3 years|
|Adults in:||June - August|
|Host plant:||polyphagous in deciduous trees|
The depicted beetle was reared from a larva found in a dead standing trunk of alder (Alnus). It was collected in Pardubice
(East Bohemia, Czech Republic).
Collected by M.Rejzek.