Some Observations onLasiorhynchus barbicornis(Brentidae: Coleoptera)

Sexual Selection in a Brentid Weevil

“…Unlike B. anchorago, however, the mandibles are enlarged in males, and play a more important role in fighting, as when one male bites down on a second male's leg, lifts him up, and drops him off the tree (Meads, 1976). Unlike B. anchorago, however, the mandibles are enlarged in males, and play a more important role in fighting, as when one male bites down on a second male's leg, lifts him up, and drops him off the tree (Meads, 1976).…”

“…Brentids make good candidates for studies of sexual selection and individual variation because most species of the family exhibit pronounced sexual dimorphism (Muizon, 1960;Haedo Rossi, 1961;Damoiseau, 1967Damoiseau, , 1971. Within each sex there is impressive phenotypic variation in body size, especially in males, which fight one another with snout and mandible for access to females (Wallace, 1869;Meads, 1976). Within each sex there is impressive phenotypic variation in body size, especially in males, which fight one another with snout and mandible for access to females (Wallace, 1869;Meads, 1976).…”

Sexual Selection in a Brentid Weevil

“…As in B. anchorago, the rostrum in L. barbicornis is longer in males (40-46% of total length), and relatively longer in the longest males. Unlike B. anchorago, however, the mandibles are enlarged in males, and play a more important role in fighting, as when one male bites down on a second male's leg, lifts him up, and drops him off the tree (Meads, 1976).…”

Observations on the ecology and behaviour of the New Zealand giraffe weevil (Lasiorhynchus barbicornis)

“…For this reason, in the current study we determined whether large-scale observations of behaviour, such as mating and fighting, would be possible in the field by developing methods for observation and insect marking. Furthermore, we aimed to build on previous work (Broun 1880;Hudson 1934;Pritchard 1952;Meads 1976;May 1993;Kuschel 2003) to extend our understanding of the natural history and host plant associations of L. barbicornis.…”

“…This is mostly due to the extreme elongation of the male rostrum, which makes up approximately half of its total body length (Kuschel 2003). Males use their rostrum during fights with other males for access to females (Meads 1976), whereas females use their rostrum to drill holes in wood before oviposition (Hudson 1934). In addition, both sexes are highly size variable, with males ranging in body length from 15 to 90 mm and females from 12 to 50 mm (Kuschel 2003;CJ Painting unpublished data).…”