Estimation of Sorting Time for Arthropod Samples Collected with Tullgren Funnels

Arthropods were sorted from samples obtained with Tullgren funnels. Each sorter maintained a log of time per session and arthropods removed per session. Five individuals removed all arthropods from 12 separate samples and sorted them into previously designated class or ordinal taxa. Each sample was sorted by a single student. Students were allowed to develop their own approaches to sorting and do it as time permitted. Mean sorting rate per sample was 2.43 arthropods per minute, with a range of 1.42-5.64, while mean sorting rate for a sorting session was 3.41 specimens per minute. Specimen density was only weakly correlated with sort time. Fatigue did not appear to be a major factor in sorting rate, as indicated by the similarity of the linear and quadratic coefficients of determination for each sample

Sticky Exudates on the Inflorescences of \u3ci\u3eCirsium Discolor\u3c/i\u3e (Asteraceae) and \u3ci\u3ePenstemon Digitalis\u3c/i\u3e (Scrophulariaceae) as Possible Defense Against Seed Predators

From 1982 through 1987, I investigated whether sticky exudates released by Cirsium discolor and Penstemon digitalis in their inflorescences provide defense against seed predators. I tested two hypotheses: 1: Exudates directly deter seed predators, and 2: Insects struggling in exudates attract predatory arthropods that remain and defend the inflorescences against seed predators. These hypotheses predict that neutralizing the stickiness will increase seed predation (by allowing access to more seed predators, or by decreasing the number of predatory arthropods attracted), and therefore decrease successful seed production. Results did not support either hypothesis, with no increase in seed predators (nor decrease in predatory arthropods), and no decrease in seed production, when traps were neutralized

Gene content evolution in the arthropods

Arthropods comprise the largest and most diverse phylum on Earth and play vital roles in nearly every ecosystem. Their diversity stems in part from variations on a conserved body plan, resulting from and recorded in adaptive changes in the genome. Dissection of the genomic record of sequence change enables broad questions regarding genome evolution to be addressed, even across hyper-diverse taxa within arthropods. Using 76 whole genome sequences representing 21 orders spanning more than 500 million years of arthropod evolution, we document changes in gene and protein domain content and provide temporal and phylogenetic context for interpreting these innovations. We identify many novel gene families that arose early in the evolution of arthropods and during the diversification of insects into modern orders. We reveal unexpected variation in patterns of DNA methylation across arthropods and examples of gene family and protein domain evolution coincident with the appearance of notable phenotypic and physiological adaptations such as flight, metamorphosis, sociality, and chemoperception. These analyses demonstrate how large-scale comparative genomics can provide broad new insights into the genotype to phenotype map and generate testable hypotheses about the evolution of animal diversity

Predatory Insects and Spiders From Suburban Lawns in Lexington, Kentucky

Predatory arthropods were caught in pitfall traps in suburban lawns in Lexington, Kentucky. The relative abundance of species of Lycosidae, Carabidae, and Staphylinidae was compared in Kentucky bluegrass and tall fescue turf. Nine species of Lycosidae were collected from both the bluegrass and tall fescue lawns. More species or phena of Carabidae were collected from bluegrass than from tall fescue turf. More than 40 species or phena of staphylinids were collected from each grass habitat. Both Kentucky bluegrass and tall fescue are inhabited by an abundant and diverse array of predatory arthropods

Arthropods Utilizing Sticky Inflorescences of \u3ci\u3eCirsium Discolor\u3c/i\u3e and \u3ci\u3ePenstemon Digitalis\u3c/i\u3e

Cirsium discolor (Muhl) Spreng (Asteraceae) and Penstemon digitalis Nutt. (Scrophulariaceae) produce sticky material only in their inflorescences. While there is a wealth of printed information concerning such sticky traps occurring in other parts of plants, there is relatively little about those specifically in inflorescences. In order to determine whether sticky traps in the inflorescences of these two plant species defend against seed predators and other herbivores and predators, it was necessary to discover what arthropods use them. Literature search revealed very little about arthropods associated with C. discolor, and nothing about those associated with P. digitalis. Observations showed that, for both plant species, pollinators do not come in contact with the traps, and each plant has several seed predators able to successfully avoid the traps. Several predatory arthropods occur on C. discolor. Two of them, a minute pirate bug and a small salticid spider, seem to glean from its sticky traps. A theridiid spider occasionally builds its web in P. digitalis inflorescences, but was not seen to glean from sticky traps. An undescribed pteromalid parasitizes one of the seed predators of P. digitalis. Ants and aphids are deterred by the traps

Can Hawaiian carnivorous caterpillars attack invasive ants or vice versa?

The Hawaiian Islands have allowed insects to evolve unique habits, because the islands are isolated and originally lacked predators, such as ants and wasps. Ambush carnivorous caterpillars (_Eupithecia_ spp.; Lepidoptera: Geometridae) provide a remarkable example of a feeding behaviour unique to the Hawaiian Islands. Their prey includes various arthropods species. _Eupithecia_ larvae even attack predatory arthropods such as parasitoids. However, it is unclear whether _Eupithecia_ can attack ants. Here, I examined whether _Eupithecia orichloris_ can attack the invasive ant _Pheidole megacephala_ under laboratory conditions. _Eupithecia orichloris_ could successfully attack the minor worker of _P. megacephala_. However, the major worker of _P. megacephala_ counterattacked.
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Bibliographic Guide to the Terrestrial Arthropods of Michigan

Papers dealing with distribution, faunal extensions, and identification of Michigan insects and other terrestrial arthropods are listed by order, and cover the period of 1878 through 1982

The Origins of Post-eruption Insect Populations on the Aleutian Island of Kasatochi

This project compares the dispersal and/or survival ability of insects on the recently erupted volcanic Aleutian Island of Kasatochi. The island erupted in 2008, two months after the island had been briefly surveyed for terrestrial arthropods. Having pre-eruption specimens provides biologists with a unique and rare perspective of island ecosystem assembly. We have analyzed the DNA of 47 pre- and post- eruption Scathophaga sp. specimens to determine the origins of post-eruption insect populations. This genetic work is especially important for the Aleutians arthropods because they are among the most understudied in the United States.Alaska EPSCoR NSF award #EPS-0701898 and the State of Alaska

Male-killing bacteria in insects: mechanisms, incidence and implications

Bacteria that are vertically transmitted through female hosts and kill male hosts that inherit them were first recorded in insects during the 1950s. Recent studies have shown these "male-killers" to be diverse and have led to a reappraisal of the biology of many groups of bacteria. Rickettsia, for instance, have been regarded as human pathogens transmitted by arthropods. The finding of a male-killing Rickettsia obligately associated with an insect suggests that the genus' members may be primarily associated with arthropods and are only sometimes pathogens of vertebrates. We examined both how killing of male hosts affects the dynamics of inherited bacteria and how male-killing bacteria affect their host populations. Finally, we assessed the potential use of these microorganisms in the control of insect populations

Arthropods Associated With Purple Loosestrife in Illinois Wetlands

We estimated and described the arthropod fauna on purple loosestrife (Lythrum salicaria) plants in northeastern Illinois wetlands. A total of 1063 individual arthropods were collected—930 insects and 133 arachnids. The av- erage number of arthropods ranged from 19.00 to 86.75 individuals per loos- estrife plants of a single root crown. We collected individuals from twenty-five families representing 8 orders of insects. Miridae, Anthocoridae, Lygaeidae, Cicadellidae, and Aphididae were each represented by at least 50 individuals. Three orders and ten families were found that had not been previously reported as occurring on purple loosestrife, but many of these taxa were represented by only a few individuals