Description of mature larvae of the four species of the Pissodes strobi complex (Coleoptera: Curculionidae)

Abstract

Mature larvae of Pissodes strobi (Peck), Pissodes schwarzi Hopkins, Pissodes nemorensis Germar, and Pissodes terminalis Hopping are described and external morphology illustrated. A key to species is presented. A phylogenetic analysis is done using single-and multiple-outgroup comparisons, which both find trees of identical topology. Character states of clypeus pigmentation and premental sclerite shape putatively support a monophyletic relationship of the I! strobi complex. Williams DJM, Langor DW. 2002. Description des larves 2 maturifi des quatre esp&ces du complexe Pissodes strobi (Coleoptera : Curculionidae). The Canadian Entomologist 134 : 9 4 5 . RCsurntGOn trouvera ici une description illustrke de la morphologie externe des larves B maturitC de Pissodes strobi (Peck), Pissodes schwarzi Hopkins, Pissodes nemorensis Germar et Pissodes teminalis Hopping. Une clC d'identification permettra de distinguer les espkces. Une analyse phylogCnCtique a Bt C faite, basCe sur des comparaisons avec un ou plusieurs groupes externes, deux mCthodes qui ont donnC des arbres de topologies identiques. Les caracteres de la pigmentation du clypCus et de la forme du sclCrite du prkmentum reflktent probablement une relation monophy-lCtique au sein du complexe I! strobi. [Traduit par la RCdaction] Corresponding author (e-mail: dawillia@nrcan.gc.ca) Drawings Images of larval structures were captured using a pixera@ digital camera (model PVC100C) attached to a Leica (model MZ8) dissecting microscope. Images were not of Volume 134 THECANADIAN ENTOMOLOGIST 1 1sufficient quality for publication, thus they were imported into ~o r e l~r a w @ 7.0 and traced to produce line drawings. Specimens studiedIn addition to larvae of the four species of the l? strobi complex, those of Pissodes afinis Randall, Pissodes striatulus Randall, Pissodes punctatus Langor and Zhang, Pissodes yunnanensis Langor and Zhang, and Pissodes rotundatus LeConte, were examined and characters that exhibited significant interspecific variation were noted. The majority of larvae were collected by the authors or various cooperators, and reared by the authors to obtain adults for mtDNA studies (Langor and Sperling 1995, 1997). Others were sent by cooperators associated with adults or damage. These larvae were used to identify diagnostic characters and delimit species concepts. Larvae borrowed from various sources (see below) were subsequently added to increase the range of morphological and geographic variation encompassed by descriptions once diagnostic characters for each species had been found and species limits confidently assigned. These additional larvae are identified by loaning institution in the Material examined section of each species description.Specimens examined were obtained from the following collections: cucc FIDS INHS FRLC NFRC PSUC Volume 134 THECANADMN LWMD~.WIST 13more rigorous treatment with increased numbers of species, specimens, and characters will have to await a larger-scale study of the genus.

Genetic divergence among populations ofPissodes yunnanensis(Coleoptera: Curculionidae) in southwestern China

“…Demographic inferences from nested clade distance analysis (Templeton et al 1995;Templeton 2004) indicates that the Nearctic P. strobi species group forms a distinct cluster, as do the two species from southwestern China, and that these two clusters are more closely related to each other than to P. affinis. This contrasts with a phylogeny of the same species based on larval morphology (Williams and Langor 2002), where P. affinis and P. yunnanensis were most related to each other and together formed a trichotomy with P. punctatus and the P. strobi complex.…”

Morphometric study of the Pissodes strobi complex (Coleoptera: Curculionidae)

“…This presumably reflects the use of the snout as an ovipositor, requiring longer snouts in females of bole-inhabiting species to penetrate thick outer bark of boles. Individuals of both sexes of P. terminalis and P. nemorensis, considered to be sister species in phylogenies based on mtDNA (Langor andSperling 1995, 1997) and larval morphology (Williams and Langor 2002), tend to be more elongate and narrower in dorsal aspect (EBEL) and more dorso-ventrally compressed (MDEL) than P. schwarzi and P. strobi. All characters measured show small but consistent differences among species, particularly when calculated as ratios with EL to control for body size.…”