Revista Chilena de Historia Natural 76 (3): 391-400, 2003
RESEARCH ARTICLE
Especialización en el uso de hospederos de Dictyneis asperatus (Blanchard
1851) en un fragmento de vegetación esclerófila-higrófila en la Península de Hualpén, Chile
We evaluated trophic relationships between the coleopteran D. asperatus
and five potencial hosts plants (Peumus boldus, Lithrea caustica, Cryptocarya alba, Aextoxicon punctatum and
Luma apiculata) in a coastal forest of the Hualpén peninsula (36º S). Leaf shape and degree of sclerophylly were
examined as possible determinants of host preferences and insect survival. Although D. asperatus was significantly more
abundant on P. boldus, there were no significant differences in consumption of leaves of P. boldus, L. caustica and
L. apiculata. Adults insects tended to stay under the concave leafs of boldo. Highest and lowest survival was
registered in insects fed on P. boldus (72%) and A. punctatum (26%) respectively. The concave leaf of
P. boldus represents a possible refuge, and the higher abundance and survival of insects, in spite of the
highly sclerophyllous nature of this species, suggests that D. asperatus is an ecological specialist in P.
boldus. However, as D. asperatus is common on other plant species at other sites, it can only be considered a
local specialist on P. boldus at Hualpén.
Key words:
Chrysomelidae,
D. asperatus, insect, trophic preferences, specialist, host plant
