Matthew S. Wallace

Field Surveys and Evaluation of Native and Established Predators of the Hemlock Woolly Adelgid (Homoptera: Adelgidae) in the Southeastern United States

Abstract There has been little research conducted on the effects of native or established predators on populations of the hemlock woolly adelgid, Adelges tsugae Annand. This study used field surveys and cage exclusion experiments to examine the relationship between established predators and A. tsugae in the southeastern United States. Predators were collected in very low densities in both years. Harmonia axyridis Pallas (Coleoptera: Coccinellidae), lacewings (Neuroptera: Chrysopidae and Hemerobiidae), and gall gnats (Diptera: Cecidomyiidae) represented 81% of the total predators collected in 1998. Cage exclusion experiments revealed no significant predator effects in all three sites in 1997 and 1998. It is unlikely that established predators are exhibiting any significant control on adelgid populations because of the low densities of predators that were encountered at a time when adelgids were abundant. Therefore, controlled releases of non-native predators into these sites should be considered.

On Dorsal Prothoracic Appendages in Treehoppers (Hemiptera: Membracidae) and the Nature of Morphological Evidence

A spectacular hypothesis was published recently, which suggested that the “helmet” (a dorsal thoracic sclerite that obscures most of the body) of treehoppers (Insecta: Hemiptera: Membracidae) is connected to the 1st thoracic segment (T1; prothorax) via a jointed articulation and therefore was a true appendage. Furthermore, the “helmet” was interpreted to share multiple characteristics with wings, which in extant pterygote insects are present only on the 2nd (T2) and 3rd (T3) thoracic segments. In this context, the “helmet” could be considered an evolutionary novelty. Although multiple lines of morphological evidence putatively supported the “helmet”-wing homology, the relationship of the “helmet” to other thoracic sclerites and muscles remained unclear. Our observations of exemplar thoraces of 10 hemipteran families reveal multiple misinterpretations relevant to the “helmet”-wing homology hypothesis as originally conceived: 1) the “helmet” actually represents T1 (excluding the fore legs); 2) the “T1 tergum” is actually the anterior dorsal area of T2; 3) the putative articulation between the “helmet” and T1 is actually the articulation between T1 and T2. We conclude that there is no dorsal, articulated appendage on the membracid T1. Although the posterior, flattened, cuticular evagination (PFE) of the membracid T1 does share structural and genetic attributes with wings, the PFE is actually widely distributed across Hemiptera. Hence, the presence of this structure in Membracidae is not an evolutionary novelty for this clade. We discuss this new interpretation of the membracid T1 and the challenges of interpreting and representing morphological data more broadly. We acknowledge that the lack of data standards for morphology is a contributing factor to misinterpreted results and offer an example for how one can reduce ambiguity in morphology by referencing anatomical concepts in published ontologies.

Occurrence of treehoppers (Hemiptera: Membracidae: Smiliinae) on oaks in delaware water gap national recreation area, 2004-2006.

Abstract A total of 870 treehoppers and 24 species from the tribe Smiliini (Hemiptera: Membracidae: Smiliinae) were collected from various oaks in the Delaware Water Gap National Recreation Area in 2006 using yellow sticky cards. Combining all years and collecting methods, 27 species were found in the park. A majority of the specimens collected in 2006 were males of Cyrtolobus vau and Ophiderma pubescens, as in previous years. Most of the treehoppers were caught in mid to late June, comparable to 2004 and 2005. It appears that many species are segregated either temporally or by oak group; some treehopper species show preference for either the red or white oak group rather than for one species of oak. Color photographs for 27 treehopper species (many including both sexes) are included.

TREEHOPPER DIVERSITY (HEMIPTERA: MEMBRACIDAE) OF LITTLE ORLEANS, ALLEGANY CO., MARYLAND

Abstract Fifty-six species (23 genera) of treehoppers (Membracidae) are recorded from the vicinity of Little Orleans, Maryland, with date and host-plant data. Eleven of the species represent new state records for Maryland, bringing the total number of species recorded for the state to 81. These data document annual collecting efforts since 1993 by the authors and others in connection with the informal treehopper conferences initiated by the late T. K. Wood. Photographs are given for 12 species representing 7 genera.

Australian treehoppers (Hemiptera : Membracidae : Centrotinae : Terentiini): phylogeny and biogeography

This work presents the first hypothesis of phylogenetic relationships among all 40 genera of the treehopper tribe Terentiini (Hemiptera : Membracidae : Centrotinae). This phylogeny, based on a parsimony analysis of 77 morphological characters, made possible an analytical approach to determining the likely ancestral host-plant family and geographic distribution of the tribe, based on present-day hosts and distributions. Of Australia’s 37 treehopper genera, 36 belong to the tribe Terentiini, with their centre of diversity in Queensland (30 genera). Optimisations of present-day distributions mapped on our phylogeny suggest that the ancestor of the tribe occurred in the Australian region, around north-eastern Australia (Queensland) and New Guinea (which has 8–10 terentiine genera). Subsequent dispersals from the Australian region (with 37 genera) took the tribe to the Indomalayan (11 genera) and Palaearctic (1 genus) regions. At least 13 terentiine genera include representatives that occur beyond the borders of Australia and New Guinea. Notable among the migrant lineages is the clade ‘Polonius + (Bulbauchenia + (Funkhouserella + Pyrgonota))’, which includes genera with such extraordinary pronotal modifications that some members were previously placed in separate tribes (Bulbaucheniini or Funkhouserellini). Members of this remarkable breakaway clade are known from Australia (Polonius only), Indonesia, the Malay Peninsula, Thailand, the Philippines, southern China (Taiwan and Hainan Island) and Japan. With regard to terentiine host plants, optimisations of present-day host associations point to the Leguminosae as the ancestral host family, even though plant families of Gondwanan origin, especially Myrtaceae and Proteaceae, are also prominent terentiine hosts. The overall evidence to date indicates that Terentiini are not a remnant of the early Gondwanan fauna, but rather a more recent tribe derived from Indomalayan ancestors.

New State Records of Treehoppers (Hemiptera: Membracidae) for Delaware, Maryland, Mississippi, Pennsylvania, And West Virginia

Abstract New state records are presented for 27 species of North American treehoppers (Membracidae) as follows: Delaware (21 spp.), Maryland (3), Mississippi (1), Pennsylvania (2), and West Virginia (1).

A New Species of Telamonini from the Eastern United States and the Taxonomic Limits of Telamona salvini Distant (Hemiptera: Membracidae: Smiliinae)

Abstract. Three similar treehopper taxa in the genus Telamona—T. salvini Distant, T. subfalcata Van Duzee, and T. stephani Wallace new species, are described and illustrated based on morphological features and geographic distributions. All three species have an acute dorsoposterior area of the pronotal projection and were historically identified in collections as Telamona salvini Distant. Telamona subfalcata Van Duzee, formerly a junior synonym of T. salvini, is reinstated from synonymy. A lectotype is also designated for T. subfalcata. Telamona stephani is the first telamonine species described from the United States in 50 years. As a result of this paper, the genus Telamona now contains 30 valid species.

Understanding age variations in the migrant mortality advantage: An international comparative perspective

This paper investigates age variations in foreign-born vs. native-born mortality ratios in an international comparative perspective, with the purpose of gaining insight into the mechanisms underlying the so-called migrant mortality advantage. We examine the four main explanations that have been proposed in the literature for the migrant mortality advantage (i.e., in-migration selection effects, out-migration selection effects, cultural effects, and data artifacts), and formulate expectations as to whether they should generate an increase, a decrease, or no change in relative mortality over the life course. Using data from France, the US and the UK for periods around 2010, we then examine typical age patterns of foreign-born vs. native-born mortality ratios in light of this theoretical framework. We find that these mortality ratios vary greatly by age, with important similarities across migrant groups and host countries. The most systematic age pattern we find is a U-shape pattern: at the aggregate level, migrants often experience excess mortality at young ages, then exhibit a large advantage at adult ages (with the largest advantage around age 45), and finally experience mortality convergence with natives at older ages. The explanation most consistent with this pattern is the “in-migration selection effects” explanation. By contrast, the “out-migration selection effects” explanation is poorly supported by the observed patterns. Our age disaggregation also shows that migrants at mid-adult ages experience mortality advantages that are often far greater than typically documented in this literature. Overall, these results reinforce the notion that migrants are a highly-selected population exhibiting mortality patterns that poorly reflect their living conditions in host countries.

Taxonomic changes in the treehopper genera Helonica Ball, Telamona Fitch, and Palonica Ball (Hemiptera: Membracidae: Smiliinae: Telamonini).

Nomenclatural changes within the treehopper tribe Telamonini are made as follows based on an examination of the type material of several species: the genus Helonica Ball is a junior synonym of Telamona Fitch, n. syn.; Telamona excelsa (Fairmaire), n. comb., with n. syn. T. unicolor Fitch; T. projecta Butler is reinstated from synonymy as a valid taxon for the North American taxa historically placed in Helonica; and Palonica albidorsata (Fowler) from Mexico, n. comb., is reinstated from synonymy based on morphological differences with T. excelsa and T. projecta. Lectotype designations are clarified for T. fasciata and T. unicolor based on specimens in the New York State Museum (NYSM). As a result of this work, the tribe Telamonini contains 68 species in 10 genera, the genus Palonica contains 7 species, and the genus Telamona contains 29 species.