The larval morphology of Tropinota squalida (Scopoli) and Aethiessa floralis (Fabricius) is described. The latter is the first description of a larva in this genus. The third-instar larva of Oxythyrea funesta (Poda) is redescribed. These species are included in a revised key to the larvae of Palaearctic Cetoniinae. The life cycle and larval biology of these flower chafers are described.

Aphids (Hemiptera: Sternorrhyncha: Aphididae) are most diverse in the temperate northern hemisphere, with only a few lineages native to the southern hemisphere. The highly diverse subfamily Aphidinae probably gained its dominance from a successful northern hemisphere radiation in the Tertiary. A few species in the tribe Aphidini, however, are indigenous to Gondwanan regions, including New Zealand and Australia. The conventional view is that these species dispersed to the south from the northern hemisphere after the main Tertiary radiation. We tested this hypothesis in a phylogenetic context by reconstructing relationships among New Zealand indigenous Aphidini, as well as their relationships to several northern taxa. Phylogenies were reconstructed from molecular data using independent and combined analyses of mitochondrial tRNA leucine cytochrome oxidase II and nuclear elongation factor-1α (EF1α) sequences, with both parsimony and maximum likelihood methods. These analyses recovered a highly supported clade of four New Zealand species in the subtribe Aphidina. On the basis of previous fossil estimates of the age of Aphidini, the New Zealand clade was calculated to date to the middle Tertiary period. A second clade of two indigenous Rhopalosiphina may be similarly ancient. In EF1α and combined analyses, New Zealand indigenous species formed the two basal lineages of Aphidina, although their positions were not supported in >50% of bootstrap pseudoreplicates. These results imply that members of Aphidinae were present in the southern hemisphere during the Tertiary radiation, and suggest a new hypothesis that at least some northern lineages were derived from southern ancestors.

Two new psychodid flies, Eophlebotomus gezei sp. nov. and E. carentonensis sp. nov., are described from Lebanese and French Lower Cretaceous ambers. They are considered here to form part of the same genus as the Upper Cretaceous Burmese amber, Eophlebotomus connectens Cockerell, 1920. These discoveries allow the description of the antenna and male genitalia of this enigmatic genus. Although the new species of Eophlebotomus share numerous characters with the Phlebotominae, especially the male genital structures, we retain this genus in the stem-group of the Sycoracinae and Trichomyiinae.

The host selection by adults of two flatheaded rootborers Capnodis tenebrionis L. and C. carbonaria Klug was investigated by examinination of their preference for feeding and oviposition among some of their major host tree taxa. We also studied the resistance to both Capnodis spp. of 10 Prunus rootstocks that were being challenged with the buprestid neonates. The scion selection for feeding and oviposition was related to the cyanide potential in the twig cortex; while potential rootstock resistance was related to the amount of the cyanogenic glycosides in the rootstock cortex. Plum and apricot were preferred by C. tenebrionis and peach was preferred by C. carbonaria. All Prunus rootstocks tested were colonized to some extent by both species. Partial correlation was found between cyanide potential and oviposition for C. carbonaria but not for C. tenebrionis. Nor was significant correlation found between cyanide potential and host preference for feeding by both species. Peach and plum, which displayed the highest level of cyanide potential, were also the preferred by both species for feeding and oviposition. Apple, with the lowest cyanide potential, was the least preferred for both activities. We found an inverse relationship between resistance to Capnodis and level of cyanogenic compounds in the root cortex. Adults of both Capnodis spp. were not deterred by high levels of cyanogenic compounds in the scion twig cortex. Our findings suggest that cyanide potential is not a reliable indicator of the degree of resistance in Prunus spp. rootstocks to Capnodis spp.

The colonization of an introduced plant by soapberry bugs in Florida has resulted in the rapid evolution of a distinctive “host race.” Differences in the synchrony and persistence of local seed crops may have favored interracial differentiation in flight/life history tactics. To advance previous work, we quantified seed availability in individual native and introduced host plants. We tested the prediction that the new host’s relatively discrete period of annual seed production has selected for a higher frequency of a short-winged, flightless morph with a briefer generation time. Contrary to that prediction, short-winged bugs were not more common in the derived race, but further investigation revealed the unexpected presence of a long-winged morph, that like the short-winged, lacks flight muscle and exhibits the same rapid life cycle advantages. Consistent with prediction, the derived race, descended from volant long-winged colonists, shows an abundance of this “cryptic” flightless morph. In total, four flight/life history morphs were discovered, including two additional long-winged types that either histolyze or retain flight muscle. The morphs differed in life history traits both within and between host races. Morph frequency may be influenced by evolution in correlated characters: we found that beak length, which has rapidly evolved to be shorter on the smaller fruits of the introduced host, is discontinuously distributed between flight morphs, being greater in long-winged bugs. This study shows complex, unpredicted evolutionary relations between a mobility character, a trophic character, and the life history.

The anatomy and histology of the alimentary canal of Dendroctonus micans (Kugelann), Dendroctonus ponderosae Hopkins, Dendroctonus pseudotsugae pseudotsugae Hopkins, Dendroctonus rufipennis (Kirby), and D. terebrans (Olivier) were described and compared. Characteristics in the structural organization of the alimentary canal in these species are comparable with those in previously studied Dendroctonus species. However, important histological differences not found in other scolytids were observed in the esophagus, crop, proventriculus, midgut, and hindgut of these species. Particularly, spines in the esophagus and crop, chitinous plates in the proventriculus, great cellular diversity in the midgut, and fine spines located in the cuticle surrounding the hindgut valve in the anterior hindgut are unique characteristics of Dendroctonus species. In the species studied, the ratio of foregut, midgut, and hindgut in relation to the total length of the alimentary canal varied slightly. This ratio did not show a relationship with insect size. Differences among the diameters of each gut region were statistically significant (P < 0.05), and the largest diameters did not necessarily appear in the largest species.

We used scanning and transmission electron microscopy in a morphological examination of the antennae of two specialist predators of the exotic hemlock woolly adelgid, Adelges tsugae Annand, as an initial step toward understanding the potential importance of olfaction in host-finding behavior. Laricobius nigrinus Fender (Coleoptera: Derodontidae) possesses six types of sensilla on a relatively long antennae comprised of scape, pedicel, and nine annuli. Two types of basiconic sensilla contained numerous wall pores with branching pore kettles and were located on the terminal three annuli. The terminal annulus contained a placoid-like sensillum, and the penultimate and antepenultimate annuli contained a coeloconic-type sensillum forming a ring around the distal portion. Two types of sensilla chaetica were located along much of the length of the antennae. Pseudoscymnus tsugae Sasaji and McClure (Coleoptera: Coccinellidae) was found to possess five types of sensilla on an extremely short antenna, which is characteristic of the tribe Scymnini, consisting of scape, pedicel, and seven annuli. Three of the annuli were void of sensilla. Two types of sensilla chaetica were located on the scape and pedicel, as well as the terminal annuli. Three types of basiconic sensilla, one of which contained numerous wall pores, were identified on the terminal two annuli. No sexual dimorphism was detected on either predator species. Our results suggest that olfaction is a more important sensory modality in L. nigrinus than P. tsugae, and that trap-based sampling methods incorporating olfactory cues are more likely to be successful for L. nigrinus than P. tsugae.

Development, location, and respiration of Compsilura concinnata (Meigen) (Diptera: Tachinidae) larvae were investigated using the silkworm, Bombyx mori (Linnaeus) (Lepidoptera: Saturniidae), as its host. C. concinnata was always found between the peritrophic membrane and the midgut of the host in the early larval stage. There they attached their posterior abdominal segment to or around the tracheoles of the host midgut using their anal hooks. C. concinnata at the later larval stage was found in the midgut cavity, where the peritrophic membrane had already been exuviated. The larvae actively took tracheae and tracheoles distributed on the coelomic surface of the host midgut into the midgut cavity.