VTechWorks Repository :: Browsing by Author "Marek, Paul E."

Browsing by Author "Marek, Paul E."

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Apheloria polychroma, a new species of millipede from the Cumberland Mountains (Polydesmida: Xystodesmidae)
Marek, Paul E.; Means, Jackson C.; Hennen, Derek A. (Zootaxa, 2018-01-25)
Millipedes of the genus Apheloria Chamberlin, 1921 occur in temperate broadleaf forests throughout eastern North America and west of the Mississippi River in the Ozark and Ouachita Mountains. Chemically defended with toxins made up of cyanide and benzaldehyde, the genus is part of a community of xystodesmid millipedes that compose several Müllerian mimicry rings in the Appalachian Mountains. We describe a model species of these mimicry rings, Apheloria polychroma n. sp., one of the most variable in coloration of all species of Diplopoda with more than six color morphs, each associated with a separate mimicry ring.
Assessing Subterranean Arthropod Diversity through COI Barcoding in Two Ecoregions of Southwestern Virginia, USA
Harrison, Garrett Taylor (Virginia Tech, 2023-06-21)
Subterranean arthropod communities are important components of North American ecosystems, contributing numerous ecosystem services and essential food-web functions. Despite this, fundamental information about species diversity in these communities remains unknown, and their taxonomic composition and ecological diversity have scarcely been assessed. Subterranean pitfall traps are a commonly used method for sampling endogean and hypogean soil habitats in Europe but have never been widely implemented in North America. Here, I employed this method to sample subterranean arthropod communities in the Ridge and Valley and Blue Ridge ecoregions of Virginia, USA in the winter and spring. In total, 2,260 arthropod specimens were collected constituting 319 distinct species. I extracted and purified DNA and amplified the mitochondrial gene: cytochrome C oxidase subunit I (COI) from each recovered morphospecies and derived a unique COI barcode for each species sequenced. Objective sequence clustering was used to establish molecular operational taxonomic units (mOTUs) for downstream diversity analyses and establishment of dynamic identification resources. Total species richness and average species richness per site were assessed and compared for both regions and seasons. The Shannon-Wiener diversity index, Hutcheson's t-test, and effective numbers of species (ENS) were employed to compare regional subterranean arthropod diversity. The richness, Shannon-Wiener, and ENS comparisons indicated that both ecoregions encompass highly diverse subterranean arthropod communities with those of the Ridge and Valley being significantly more diverse than those of the Blue Ridge.
Biodiversity, conservation and mimicry rings of Appalachian millipedes
Means, Jackson C. (Virginia Tech, 2019-01-18)
The Appalachian Mountains contain some of the highest millipede diversity on the planet, including many endemic and range-restricted species. Millipedes have extremely low dispersal capacity, strict environmental requirements for survival and, in the case of the family Xystodesmidae, are completely blind. Coupled with the complex topology of the Appalachians, xystodesmid millipedes have speciated in the eastern United States to a greater degree than in any other region. Many of the taxonomic relationships within the Xystodesmidae remain to be tested using modern molecular techniques, and numerous species await description. The subtribe Nannariina, for example, contains 3 genera and 19 species, yet evidence suggests the tribe may actually contain over 100 species. Traditional taxonomic work has been hindered by a paucity of researchers in the field, and a necessary reliance on morphological characters for species delimitation. The external male genitalia, known as gonopods, are the structures which have most often been used to define species boundaries. However, in many groups, including the Xystodesmidae, the gonopods are extremely simple, making it difficult to discern whether similarity between gonopods is a result of shared ancestry or morphological convergence. Further complicating matters, somatic characters are often uniform between species, and some obvious phenotypes, such as color pattern and hue, are shared between genera in aposematic mimicry rings. Leading to the formation of mimicry rings between distantly related genera, their bright coloration functions to advertise a cyanide-based defense. Some species have been recorded as having six color patterns, each a member of a different mimicry rings. The factors which drive some taxa to participate in mimicry rings, while others have a myriad of hues and patterns, unmatched by other species, are unknown. Here I investigate the phylogenetic relationships between the tribes and genera of the Xystodesmidae, with the aims of (1) understanding the role of homoplasy within the Xystodesmidae, (2) delineating tribal and generic boundaries within the family, (3) describing species in the genus Nannaria for the purposes of revising the subtribe Nannariina, and (4) investigating mimicry and color variability through a detailed color atlas for North American Xystodesmidae. I found that 95% of the morphological characters traditionally used in xystodesmid taxonomy are homoplasious (HI > 0.5), delineated the Apheloriini, Appalachioria and Sigmoria, described 34 new Nannaria species, and created a color and mimicry dataset of 956 Xystodesmidae for use in future studies of color variability.
Biological Studies and Evaluation of Scymnus Coniferarum, a Predator of Hemlock Woolly Adelgid from Western North America
Darr, Molly Norton (Virginia Tech, 2017-06-07)
The hemlock woolly adelgid (HWA), Adelges tsugae Annand, is an invasive pest of eastern hemlock, Tsuga canadensis (L.) Carriere and Carolina hemlock Tsuga caroliniana Englem. in the eastern United States. A newly reported beetle predator for HWA, Scymnus (Pullus) coniferarum Crotch (Coleoptera: Cocinellidae) preys on the pest in the western United States, and was approved for release in the eastern United States for the control of HWA. This research investigated the viability of S. coniferarum as a biological control agent of A. tsugae in the eastern United States, as well as the ecological dynamics between S. coniferarum and host prey species in its native range of western North America. In objective one, S. coniferarum predation, reproductive potential, and survival were evaluated in field-cages on adelgid infested T. canadensis in southwestern Virginia. Adult S. coniferarum fed on both generations and all life stages of A. tsugae at rates comparable to other adelgid-specific predators, and survived for extended periods of time in the field. In objective two, host-range tests for S. coniferarum were conducted in a series of no-choice and paired-choice feeding, oviposition, and development studies. Scymnus coniferarum adults fed on all adelgid species, and completed development on HWA and Adelges piceae Ratz. Scymmnus coniferarum oviposition was extremely low. In the final objective, Douglas-fir, Pseudotusga menziesii Mirb., Shore pine, Pinus contorta Dougl., western white pine, Pinus monticola Dougl., and western hemlock, Tsuga heterophylla (Raf.) Sarg. host tree species were sampled in Tacoma, Washington to investigate the life history of S. coniferarum and associated adelgid prey species in the western United States. Scymnus coniferarum adults were found on both pine species, Douglas fir, and western hemlock, and seemed to move between host tree species seasonally. Each host tree supports a different adelgid species, and a limited diet of strictly HWA in host-range tests could have contributed to low oviposition rates. This study suggested that S. coniferarum is a voracious predator of HWA in the field and laboratory. However, S. coniferarum laid very few eggs in laboratory studies, and zero eggs were recovered in field-cage analyses. This suggested that S. coniferarum may rely on multiple adelgid species to reproduce and establish in the eastern United States.
A biologically accurate model of directional hearing in the parasitoid fly Ormia ochracea
Mikel-Stites, Max R.; Salcedo, Mary K.; Socha, John J.; Marek, Paul E.; Staples, Anne E. (Cold Spring Harbor Laboratory, 2021-09-17)
Although most binaural organisms localize sound sources using neurological structures to amplify the sounds they hear, some animals use mechanically coupled hearing organs instead. One of these animals, the parasitoid fly Ormia ochracea, has astoundingly accurate sound localization abilities and can locate objects in the azimuthal plane with a precision of 2°, equal to that of humans. This is accomplished despite an intertympanal distance of only 0.5 mm, which is less than 1/100th of the wavelength of the sound emitted by the crickets that it parasitizes. In 1995, Miles et al. developed a model of hearing mechanics in O. ochracea, which works well for incoming sound angles of less than ±30°, but suffers from reduced accuracy (up to 60% error) at higher angles. Even with this limitation, it has served as the basis for multiple bio-inspired microphone designs for decades. Here, we present critical improvements to the classic O. ochracea hearing model based on information from 3D reconstructions of O. ochracea’s tympana. The 3D images reveal that the tympanal organ has curved lateral faces in addition to the flat front-facing prosternal membranes represented in the Miles model. To mimic these faces, we incorporated spatially-varying spring and damper coefficients that respond asymmetrically to incident sound waves, making a new quasi-two-dimensional (q2D) model. The q2D model has high accuracy (average errors of less than 10%) for the entire range of incoming sound angles. This improved biomechanical hearing model can inform the development of new technologies and may help to play a key role in developing improved hearing aids. Significance Statement: The ability to identify the location of sound sources is critical to organismal survival and for technologies that minimize unwanted background noise, such as directional microphones for hearing aids. Because of its exceptional auditory system, the parasitoid fly Ormia ochracea has served as an important model for binaural hearing and a source of bioinspiration for building tiny directional microphones with outsized sound localization abilities. Here, we performed 3D imaging of the fly’s tympanal organs and used the morphological information to improve the current model for hearing in O. ochracea. This model greatly expands the range of biological accuracy from ±30° to all incoming sound angles, providing a new avenue for studies of binaural hearing and further inspiration for fly-inspired technologies.
Cache Valley Virus in Aedes japonicus japonicus Mosquitoes, Appalachian Region, United States
Yang, Fan; Chan, Kevin K.; Marek, Paul E.; Armstrong, Philip M.; Liu, Pengcheng; Bova, Jacob E.; Bernick, Joshua N.; McMillan, Benjamin E.; Weidlich, Benjamin G.; Paulson, Sally L. (2018-03)
We detected Cache Valley virus in Aedes japonicus, a widely distributed invasive mosquito species, in an Appalachian forest in the United States. The forest contained abundant white-tailed deer, a major host of the mosquito and virus. Vector competence trials indicated that Ae. j. japonicus mosquitoes can transmit this virus in this region.
Chromosomal evolution in mosquitoes - vectors of diseases
Naumenko, Anastasia Nikolayevna (Virginia Tech, 2017-06-23)
The World Health Organization estimates that vector-borne diseases account for 17% of the global burden of all infectious diseases and has identified the mosquito as the most dangerous of all disease-transmitting insects, being responsible for several million deaths and hundreds of millions of cases each year. The study of mosquito genomics provides a deeper understanding of the molecular mechanisms involved in every aspect of vector biology, such as sex determination, host-parasite interaction, ecology, feeding behavior, immunity and evolutionary trends and can be used for the development of new strategies for vector control. We developed the first map of the mitotic chromosomes of the major vector for West Nile fever and lymphatic filariasis, Culex quinquefasciatus. The map was then successfully utilized for mapping of approximately 90% of available genetic markers to their precise positions on the chromosomes. Idiograms were integrated with 140 genetic supercontigs representing 26.5% of the genome. A linear regression analysis demonstrated good overall correlation between the positioning of markers on physical and genetic linkage maps. This will improve gene annotation and help in distinguishing potential haplotype scaffolds and regions of segmental duplications. It will also facilitate identification of epidemiologically important genes that can be used as targets for the vector control and provide a better framework for comparative genomics that will help understanding of the evolution of epidemiologically important traits. In another study, we confirmed the presence of the newly described species, Anopheles daciae, in regions of Russia using molecular data. Although sympatric with its sibling species, Anopheles messeae, five nucleotide substitutions in the internal transcribed spacer 2 of ribosomal DNA can be used to distinguish the morphologically similar species. Chromosome rearrangements have a significant impact on mosquito adaptation and speciation. Using sequencing data in combination with karyotyping, we demonstrated that significant differences in inversion frequencies distinguish An. messeae from An. daciae, suggesting that these inversions are actively involved in adaptation and speciation. It is essential to have reliable toolbox for correct identification of these species and to know their range for future possible malaria outbreaks prevention.
Chromosome evolution and mechanisms of speciation in the Anopheles gambiae complex
Liang, Jiang-tao (Virginia Tech, 2020-06-01)
Malaria is a life-threatening disease caused by Plasmodium parasites that are transmitted through the bites of infected females of a few Anopheles mosquito species. Understanding the chromosome evolution and mechanisms of speciation can shed light on developing novel ecological-friendly vector control techniques. Sibling species of the An. gambiae complex provide an excellent model system for these topics. To understand the mechanisms of speciation, we investigated the cellular basis and phenotypes of hybrid male sterility in species crosses of the An. gambiae complex. By performing inter-species crosses of An. coluzzii/An. gambiae and An. merus lab strains, we found an asymmetric pattern of hybrid male sterility existed in sons from reciprocal interspecies crosses. Compared with pure species, hybrid males from crosses of ♀An. merus  ♂An. gambiae/An. coluzzii were normal in the morphology of male reproductive tracts; however, the testes of which that process the reductional meiotic division failed to produce primary spermatocytes and were accompanied with unpaired and insufficiently condensed chromosomes. As a result, primary spermatocytes undergo a mitosis-like anaphase division, producing nonmotile and malfunctional diploid sperm with two tails. However, individuals can mate with females normally and form the mating plug to induce the female monogamy. In contrast, hybrid males from the opposite crosses manifest severely underdeveloped reproductive tracts and a premeiotic arrest of germline stem cells in the testis, accompanied by a strong suppression of premeiotic and meiotic genes. In addition, hybrid males from this cross suffered from a shorter copulation time and failed to form mating plugs to induce female monogamous behaviors, albeit the expression of male accessory gland specific genes were similar between hybrids and pure species. To figure out chromosome evolution in the An. gambiae complex, we studied the molecular organization of heterochromatin and investigated the spatial organizations of autosomal regions of polytene chromosomes in soma and germline cells. We found that molecular composition of pericentrometric autosome and sex chromosome repetitive DNA differs among sibling species of An. gambiae complex with highly similarity between An. coluzzii and An. arabiensis. In addition, heterochromatin blocks of chromosomes have distinct compositions of satellite DNA sequences. Next, in order to address the relationship between inter-chromosomal (Chr-Chr) contacts and chromosome-nuclear envelope (Chr-NE) attachments during the development of the organism, we conducted microscopic analyses of the 3D organization of polytene chromosome in An. gambiae, An. coluzzii, and An. merus. Our quantitative study on chromosome territories in larval salivary gland cells and adult ovarian nurse cells showed that, compared with autosomal arms, the X chromosome has a significantly smaller volume and occupies more compact territories. The number of Chr-Chr contacts and the percentage of Chr-NE attachment were conserved among the species within the same cell type. Our data also demonstrated that there is a significantly and consistently inverse relationship between the frequencies of Chr–NE and Chr–Chr attachments on autosomes of two cell types in all tested species.
Comparing University Entomology Outreach Events While Examining Public Views of Arthropods and Pesticides
Blevins, Stephanie Lynn (Virginia Tech, 2018-10-12)
Hokie BugFest is an annual free event designed by the Entomology Department at Virginia Tech to translate the importance of entomology to the public. The event has grown from 2,000 attendees in 2011 to over 8,000 attendees in 2017. Entomology faculty, staff, graduate students and alumni partner with Virginia Cooperative Extension, Virginia 4-H, and other entities to provide an educational experience to the public. The goal of this outreach event is to showcase entomological research, increase public awareness, elevate the appreciation of entomology, develop better public perceptions of insects and other arthropods, and educate participants about pesticide safety and pest management practices. Although many institutions host entomology outreach events like Hokie BugFest (Frazier, 2002; Hamm and Rayor, 2007; Hvenegaard et al., 2013), little research has been conducted to compare the impact of these activities. Whether these events impact public attitudes toward insects and other arthropods is also lacking (Pitt and Shockley, 2014). Several studies have been conducted in other states to investigate public attitudes toward arthropods and pesticides (Baldwin et al., 2008; Byrne et al., 1984; Frankie and Levenson, 1978; Hahn and Ascerno, 1991; Potter and Bessin, 1998); however, research is missing in Virginia. In order to contribute to this literature, three surveys were developed. One survey focused on investigating entomology outreach events similar to Hokie BugFest. Results revealed that event structure, attendance, funding sources, and popular exhibits impact the hosting institution and the surrounding communities. The other two surveys focused on gauging the impacts Hokie BugFest has on youth and adult attendees. Results indicated the event has a positive impact on attendee perceptions of insects, other arthropods, and pesticides.
Cryptic diversity in Andrognathus corticarius Cope, 1869 and description of a new Andrognathus species from New Mexico (Diplopoda, Platydesmida, Andrognathidae)
Shorter, Patricia L.; Hennen, Derek A.; Marek, Paul E. (ZooKeys, 2018-09-25)
Andrognathus is a genus of small, thin-bodied millipedes found in deciduous forests of North America. Poorly understood, these organisms inhabit decaying wood and have morphologically conserved and difficult-to-identify sexual characters that have limited study historically. Recent use of scanning electron microscopy has uncovered variation in male genitalia that was previously unknown in the genus. The distribution of Andrognathus and the extent of this variability across the continent, however, were undocumented, and a wealth of natural history collections remained uncatalogued. Here a new species of Andrognathus is described from New Mexico, Andrognathus grubbsi sp. n., natural history collections are utilized to create a comprehensive map of the genus, and a neotype established for the type species, Andrognathus corticarius Cope, 1869. Analysis of the cytochrome oxidase I gene (COI) for A. corticarius was completed for the type series and individuals across the species distribution, but little variation was found. Andrognathus grubbsi sp. n. joins A. corticarius and A. hoffmani Shear & Marek, 2009 as the only members of the genus.
Effects of Farm Management Practices on Pest Slugs and Slug Predators in Field Crops
Brichler, Kirsten Nicole (Virginia Tech, 2020-05-18)
Mid-Atlantic crop producers are increasingly transitioning to soil conservation methods that include reducing or eliminating tillage and planting high residue cover crops. These practices are associated with an increase in moderate to severe damage to field crops by slugs. Conserving, and even enhancing, natural enemy populations is a desirable way to manage slug infestations because remedial control measures are limited. To better understand how cover crop usage and tillage practices affect slug and natural enemy populations, 43 Virginia fields with different combinations of tillage practices and cover crop use were intensively sampled in 2018 and 2019. Fields were sampled over a six-week period during the early planting season when slugs are most problematic. Shingle traps and pitfall traps were used to sample slugs and natural enemies, respectively. To determine how multiple farming practices, soil composition, landscape features, and field history affect slug feeding injury to seedling plants, over 1,000 hectares of commercial production fields in the Shenandoah Region of Virginia were scouted for slug feeding injury to seedling plants. Corresponding crop producers were then surveyed on management methods. Our goal was to determine if slug feeding risk could be predicted by a single factor and or a combination of factors. Behavioral assays were performed with a common slug pest, Deroceras laeve, to determine if this species prefers feeding on maize, soybean, daikon radish, crimson clover, rye, or hairy vetch leaf tissue. Our sampling study found that cover crop use and conservation tillage type did not affect slug presence and damage, but that these factors affected various slug predators in different ways. We also observed that fields with more Phalangiidae and total predators overall had fewer slugs. Average slug feeding injury in both years was low and no factor or interaction of factors in our broader survey affected slug feeding injury ratings in fields. Behavioral assays indicated that slugs fed more on soybean tissue compared with maize, slugs consumed less maize when it was offered with hairy vetch or crimson clover, and slugs consumed less soybean when it was offered with hairy vetch or daikon radish.
Factors influencing arbovirus transmission: vector competence and the effects of virus infection on repellent response, oxidative stress, and glutathione-S-transferase activity
Chan, Kevin Ki Fai (Virginia Tech, 2020-01-31)
Zika (ZIKV), La Crosse (LACV), and Cache Valley (CVV) viruses are mosquito-vectored diseases that cause significant morbidity and mortality in humans and animals. Transmission of these viruses are dependent on numerous factors including vector competence and the effects of mosquito-virus interactions. We conducted vector competence studies of local Aedes and Culex mosquitoes for ZIKV and CVV, and found that all Aedes mosquitoes were competent for CVV and only Aedes albopictus and Aedes japonicus were competent for ZIKV. Vector competence for CVV was dose-dependent, where mosquitoes orally infected with high titers developed higher transmission rates. We also found that vector competence for ZIKV was limited by midgut and salivary gland barriers. Second, we looked at the effects of LACV and ZIKV infection on repellent response in Aedes mosquitoes and found that infected mosquitoes were refractory to low concentrations of DEET, picaridin, and PMD. Increasing concentrations of the repellents to ≥10% was able to increase percent protection (%p) against infected and uninfected mosquitoes. Lastly, we determined the effects of ZIKV and LACV infection on oxidative stress and glutathione-S-transferase (GST) activity in Aedes albopictus. Virus infection had no effect on oxidative stress, but GST activity was significantly different for mosquitoes 3-days post-exposure. We found that oxidative stress levels and GST activity had an inverse relationship for infected and uninfected mosquitoes, where oxidative stress decreased and GST activity increased over the 10-day test period. This indicates that GSTs may aid in controlling byproducts of oxidative stress. The results from this entire study identified competent vectors for emerging arboviruses and demonstrated the behavioral and physiological effects of virus infection in the mosquito vector.
The first true millipede—1306 legs long
Marek, Paul E.; Buzatto, Bruno A.; Shear, William A.; Means, Jackson C.; Black, Dennis G.; Harvey, Mark S.; Rodriguez, Juanita (Springer, 2021-12-01)
The name “millipede” translates to a thousand feet (from mille “thousand” and pes “foot”). However, no millipede has ever been described with more than 750 legs. We discovered a new record-setting species of millipede with 1,306 legs, Eumillipes persephone, from Western Australia. This diminutive animal (0.95 mm wide, 95.7 mm long) has 330 segments, a cone-shaped head with enormous antennae, and a beak for feeding. A distant relative of the previous record holder, Illacme plenipes from California, it belongs to a different order, the Polyzoniida. Discovered 60 m below ground in a drill hole created for mineral exploration, E. persephone possesses troglomorphic features; it lacks eyes and pigmentation, and it has a greatly elongated body—features that stand in stark contrast to its closest surface-dwelling relatives in Australia and all other members of its order. Using phylogenomics, we found that super-elongation (> 180 segments) evolved repeatedly in the millipede class Diplopoda. The striking morphological similarity between E. persephone and I. plenipes is a result of convergent evolution, probably for locomotion in similar soil habitats. Discovered in the resource-rich Goldfields-Esperance region and threatened by encroaching surface mining, documentation of this species and conservation of its habitat are of critical importance.
The identity of Neocnemodon calcarata (Loew) (Diptera: Syrphidae), a specialized flower fly predator of woolly apple aphid
Bergh, J. Christopher; Marek, Paul E.; Short, Brent D.; Skevington, Jeffrey H.; Thompson, F. Christian (2023-03-05)
The names and identities of the specialized flower fly predators of the Woolly Apple Aphid, Eriosoma lanigerum (Hausmann, 1802) are fixed. These predators, Neocnemodon calcarata (Loew, 1866) and Neocnemodon vitripennis (Meigen, 1822), are important biological control agents as they prey on both arboreal and root colonies of the aphid. A lectotype is designated for Pipiza calcarata Loew, 1866, and type notes of N. calcarata and N. vitripennis are provided.
Investigating the natural history and predator complex of the native pine bark adelgid (Pineus strobi) in southwestern Virginia
Wantuch, Holly Anne (Virginia Tech, 2018-02-27)
The pine bark adelgid, Pineus strobi (Hemiptera: Adelgidae) is a native herbivore of eastern white pine, Pinus strobus (Pinales: Pinaceae), in eastern North America. It is a sessile insect that settles on P. strobus and inserts its stylet bundle to feed on the tree’s phloem. Although P. strobi is not considered a serious pest, it shares its range with the invasive hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae). Predators introduced as biological control agents of A. tsugae interact with P. strobi and its native predators, including Laricobius rubidus LeConte (Coleoptera: Derodontidae). Prior to this study, little work had been done to document the phenology or predators of P. strobi, particularly in its southern range. In the present study, the phenology of P. strobi is reported in southwestern Virginia. Patterns in overwintering population dynamics varied notably from those described from this species’ northern range. The number of annual generations could not be measured due to overlap following two distinct spring generations. Adult body size varied seasonally and was greatest in the spring. Variation between observations from the northern and southern ranges of P. strobi indicate phenological plasticity that informs biological control efforts and offers insight into implication of climatic effects on population dynamics of this and related species. Arthropod predators associated with P. strobi in forests of southwest Virginia were collected during a two-year survey. Morphology and DNA barcoding were used for identification. Species of predators found included: Laricobius rubidus (Coleoptera: Derodontidae), a native adelgid specialist, and two species from the dipteran family Chamaemyiidae, Leucopis piniperda Malloch and L. argenticollis Zetterstedt, which are adelgid specialists. Members of the families Cecidomyiidae, Coccinellidae, Chrysopidae, Hemerobiidae, and Syrphidae were also recovered. Most diverse were the Cecidomyiidae, with 15 different species inferred from their DNA barcodes. Additional work was performed to quantify supercooling points of L. rubidus collected from November – December 2016. These will be compared to those of other Laricobius species in a parallel study. Knowledge of this predator complex is beneficial to describing P. strobi ecology, and also with regard to potential biological control of invasive adelgids in the same region.
Is geography an accurate predictor of evolutionary history in the millipede family Xystodesmidae?
Means, Jackson C.; Marek, Paul E. (PeerJ, 2017-10-12)
For the past several centuries, millipede taxonomists have used the morphology of male copulatory structures (modified legs called gonopods), which are strongly variable and suggestive of species-level differences, as a source to understand taxon relationships. Millipedes in the family Xystodesmidae are blind, dispersal-limited and have narrow habitat requirements. Therefore, geographical proximity may instead be a better predictor of evolutionary relationship than morphology, especially since gonopodal anatomy is extremely divergent and similarities may be masked by evolutionary convergence. Here we provide a phylogenetics-based test of the power of morphological versus geographical character sets for resolving phylogenetic relationships in xystodesmid millipedes. Molecular data from 90 species-group taxa in the family were included in a six-gene phylogenetic analysis to provide the basis for comparing trees generated from these alternative character sets. The molecular phylogeny was compared to topologies representing three hypotheses: (1) a prior classification formulated using morphological and geographical data, (2) hierarchical groupings derived from Euclidean geographical distance, and (3) one based solely on morphological data. Euclidean geographical distance was not found to be a better predictor of evolutionary relationship than the prior classification, the latter of which was the most similar to the molecular topology. However, all three of the alternative topologies were highly divergent (Bayes factor >10) from the molecular topology, with the tree inferred exclusively from morphology being the most divergent. The results of this analysis show that a high degree of morphological convergence from substantial gonopod shape divergence generated spurious phylogenetic relationships. These results indicate the impact that a high degree of morphological homoplasy may have had on prior treatments of the family. Using the results of our phylogenetic analysis, we make several changes to the classification of the family, including transferring the rare state-threatened species Sigmoria whiteheadi Shelley, 1986 to the genus Apheloria Chamberlin, 1921—a relationship not readily apparent based on morphology alone. We show that while gonopod differences are a premier source of taxonomic characters to diagnose species pairwise, the traits should be viewed critically as taxonomic features uniting higher levels.
La Crosse Virus in Aedes japonicus japonicus Mosquitoes in the Appalachian Region, United States
Harris, M. Camille; Dotseth, Eric J.; Jackson, Bryan T.; Zink, Steven D.; Marek, Paul E.; Kramer, Laura D.; Paulson, Sally L.; Hawley, Dana M. (2015-04)
La Crosse virus (LACV), a leading cause of arboviral encephalitis in children in the United States, is emerging in Appalachia. For local arboviral surveillance, mosquitoes were tested. LACV RNA was detected and isolated from Aedes japonicus mosquitoes. These invasive mosquitoes may significantly affect LACV range expansion and dynamics.
The milliped family Striariidae Bollman, 1893. V. Stegostriaria dulcidormus, n. gen., n. sp., Kentrostriaria ohara, n. gen., n. sp., and the convergent evolution of exaggerated metazonital crests (Diplopoda, Chordeumatida, Striarioidea)
Marek, Paul E.; Shear, William A. (Magnolia Press, 2022-02-04)
Two new genera and species, Stegostriaria dulcidormus (Trisariinae) and Kentrostriaria ohara (Striariinae), are described from Oregon and Idaho, respectively. The new species are distinct from any other striariids, and indeed from any other chordeumatidan millipedes, in having the second dorsal crests greatly enlarged, giving them a fanciful resemblance to stegosaurid dinosaurs. In spite of this similarity, the two species are so distinct they cannot be accommodated in the same genus or the same subfamily. The exaggerated metazonital crests are therefore attributed to convergent evolution. We present a key to the genera of the family Striariidae.
The millipede family Striariidae Bollman, 1893. IV. Amplaria oedipus, n. sp., with a secondary sexual modification of males unique among millipedes (Diplopoda, Chordeumatida, Striarioidea)
Shear, William A.; Nosler, Philip; Marek, Paul E. (Magnolia Press, 2022-02-10)
A new species, Amplaria oedipus, is described from Oregon, USA. Males of the new species have greatly inflated pyriform tarsi on the 5th and 6th legpairs, which is a secondary sexual modification previously not known from any other millipede.
The millipede family Striariidae Bollman, 1893. VIII. Three new genera and four new species of minute millipedes from Oregon and Washington, USA (Diplopoda, Chordeumatida, Striarioidea)
Shear, William A.; Marek, Paul E. (Magnolia Press, 2023-04-14)
We describe three new genera and four new species of small, litter-dwelling millipedes from the states of Oregon and Washington, USA: Miniaria ramifera, n. gen., n. sp., Miniaria richarti, n. gen., n. sp., Tigraria oregonensis, n. gen., n. sp., and Kingaria prattensis, n. gen., n. sp. Some of the unusual characters of these species are discussed, including a new type of sensory array on the third tarsus of males and a newly observed mandibular gland.

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