Three Species of Long-horned Beetles Feeding on Taiwan Red Pine

Abstract

Recent evidence has shown that the native Taiwan red pine (Pinus taiwanensis), once believed to be a resistant pine species, is subject to pinewood nematode Bursaphelenchus xylophulus attack. Because the pine sawyer, Monochamus alternates, has been confirmed as the major vector of the pinewood nematode, attempts were made to collect pine sawyers and other long-homed beetles in Taiwan red pine forests. A total of 28 adults and 42 larvae of 3 species of long-horned beetles, namely Acanthocinus gundaicnsis, M. alternatus, and Paraleprodera irzingeri, was found to be associated with dying and dead trees of Taiwan red pine. Based on this limited data, A. gundaiensis and P. itzingeri were more abundant than M. alternates in Taiwan red pine forests. Most significantly, 1 of the 16 newly emerged P. itzingeri was found to be carrying 7 Bursaphelenchus nematodes. This and the similarity of the feeding behavior of P. itzingeri and M. alternatus suggest that P. itzingeri may be a potential vector of the pinewood nematode in Taiwan red pine forests. This is the first report that Taiwan red pine is a host plant of M. alternatus and the endemic P. itzingeri and A. gundaiensis. The impact of these 3 species of long-horned beetles on Taiwan red pine must be understood and assessed before control measures directed at them, in an attempt to regulate the pinewood nematode in Taiwan red pine forests, can be implemented.