The role of sex and mating status in the expansion process of Arhopalus rusticus - an exotic cerambycid in Argentina

GRILLI M.P,; FACHINETTI, R

ENVIRONMENTAL ENTOMOLOGY

ENTOMOLOGICAL SOC AMER

Lugar: Lanham; Año: 2017 p. 714 - 721

0046-225X

In Córdoba province, central Argentina, there is an area of introduced pine trees. In 15 2006, an invading Cerambycid, Arhoplus rusticus, was detected in this region for the 16 first time. The species has since expanded its range until it now occupies the whole area.  17 A.  rusticus  is  a  common  species  of  cerambycid  in  pine  forests  of  the  northern 18 hemisphere.  In  this  paper,  we  analyze  how  sex  and  mating  status  affects  flight 19 performance and the potential distribution of this species. The study was performed 20 with individuals collected from introduced pine forests in the center-west of Córdoba 21 Province (Argentina). The dispersal capability of Arhopalus rusticus was determined by 22 putting recently emerged mated and unmated individuals to fly in flight mills. Data of 23 pre-flight  body  weight,  post-flight  body  weight,  body  length  and  elytron  size  were 24 obtained from the individuals that were put to fly. We found that females were bigger, 25 heavier, with longer elytra and were better flyers than males. We also found statistical 26 differences  between  dispersal  potential  depending  on  the  mating  status.  Mated 27 individuals flew faster and longer distances than unmated ones, and also consumed a 28 smaller fraction of their body weight. A positive relationship was observed between 29 elytra size and flight speed. A map of males? and females? dispersal distances was 30 produced for the study region using the adjusted dispersal distance distribution of males 31 and females. The flight performance of males and females showed that, as females 32 disperse  after  copulation,  they  increase  the  chances  of  establishing  the  species  in 33 unoccupied areas.