Publications by EEOB faculty January 1 - January 31

January 30, 2019
eeob 2016

Philippinozercon, a new genus of Heterozerconidae (Parasitiformes: Mesostigmata), with description of all active instars


The generic classification of millipede associated Heterozerconidae in the Oriental region is revised. The genus Allozercon Vitzthum is re-diagnosed and Asioheterozercon Fain is designated as an subjective junior synonym of Allozercon. Philippinozercon gen. nov., with the type species P. makilingensis sp. nov., is described for all instars. This genus may be endemic for the Philippines, but is quite widespread in that country. All immature instars are described, making this the second species of Heterozerconidae known for all instars. The morphology of the immatures is compared with that of immatures of the temperate species Narceoheterozercon ohioensis and unnamed species from Brazil and Thailand. All immatures were collected from millipede frass and litter, never from millipedes. Adults are associated with millipedes in the family Trigoniulidae (Spirobolida).

Opportunities for female choice in the bed bug Cimex lectularius

Susan N. Gershman  Scott A. Harrison  Susan C. Jones. 2019.


Bed bugs are cited as exemplars of sexual conflict because mating can only occur via traumatic insemination. However, past antagonistic coevolution between the sexes does not necessarily preclude current female choice. Here, we investigate opportunities for precopulatory female choice in bed bugs. We examined whether females seek out mating opportunities when they gain the most benefit: when females are virgin and/or have recently fed. But, we found that female mating and feeding status had little effect on female attraction to males and male odor. To determine whether females approach male harborages (home crevices) to seek matings in nature, we investigated where matings occurred among unfamiliar pairs of bed bugs. We found that, despite female attraction to male odor, matings were most likely to take place in the female's harborage rather than the male's harborage. We also examined the effect of feeding on male and female ability to mate. Whereas previous research reported that engorgement impaired female ability to refuse matings, we found that male feeding status had a larger effect on the success of mating encounters than female feeding status. Fed males had poor mating success, suggesting that males may be faced with a trade‐off between mating and feeding.

New species of Idris Förster (Hymenoptera, Platygastroidea) from southeast Asia, parasitoids of the eggs of pholcid spiders (Araneae, Pholcidae)

Norman F. Johnson, Huayan Chen, Bernhard Huber. 2019. doi: 10.3897/zookeys.811.29725


Four new species of the genus Idris Förster (Hymenoptera: Platygastroidea), reared from the eggs of pholcid spiders (Araneae: Pholcidae) in southeast Asia are described on the basis of external morphology and the barcode region of the mitochondrial COI gene. The new species and their hosts are: I. badius Johnson & Chen, sp. n. (ex Nipisa phyllicola (Deeleman-Reinhold), Panjange hamiguitan Huber), I. balteus Johnson & Chen, sp. n. (ex Panjange camiguin Huber), I. curtus Johnson & Chen, sp. n. (ex Calapnita nunezae Huber, Panjange camiguin Huber, Tissahamia bukittimah (Huber), Uthina luzonica Simon), and I. fusciceps (ex Belisana khaosok Huber).

Penstemon reidmoranii (Plantaginaceae), a new species from Baja California, Mexico



Penstemon reidmoranii is described from the southern region of the state of Baja California, Mexico. This new species belongs to the subgenus Penstemon, section Peltanthera, subsection Peltanthera, and is distinguished primarily by its length, shape, margin and texture of the leaves. In addition, the staminode is covered in almost its full length by glandular hairs, while towards the apex it bears long white hairs of 6 mm long. Here, we describe and illustrate this new species. We also provide a distribution map and a comparison with Penstemon eximius, a morphologically similar taxon.

Hydroacoustic data‐analysis recommendations to quantify prey‐fish abundance in shallow, target‐rich ecosystems

Rebecca A. Dillon  Joseph D. Conroy  Stuart A. Ludsin. 2019.

Standardized sampling methods can benefit fisheries management by facilitating comparison of fish abundance estimates within and among ecosystems. Towards developing an improved standardized hydroacoustic method for estimating prey‐fish abundance and target strength in small (surface areas < 15 km2), shallow (max depths < 20 m) freshwater ecosystems (e.g., north‐temperate reservoirs), we evaluated how the incorporation of several recommended hydroacoustic data‐analysis procedures from the Great Lakes Standard Operating Procedures (GLSOP; Parker‐Stetter et al. 2009) into an existing hydroacoustic protocol used in north‐temperate reservoirs (Ohio Department of Natural Resources, Division of Wildlife, DOW; ODNR DOW 2015) influenced estimates of prey‐fish abundance. To facilitate our evaluation, we conducted hydroacoustic surveys in four Ohio, USA reservoirs during August 2016, and then compared prey‐fish abundance estimates generated from the existing DOW reservoir protocol to those that included three GLSOP recommendations separately and in combination. The three recommendations were: 1) removal of background noise; 2) use of a lower maximum beam compensation (MBC) setting; and 3) application of the Sawada index (Nv) to identify and replace biased in situ, cell‐specific target strengths. Our analyses showed that the removal of background noise (‐0.1 to 0% change) and application of Nv (‐7.8 to 0% change) had little substantive effect. However, decreasing the MBC from 12 to 6 dB significantly reduced prey‐fish abundance estimates (4.1 to 16.1% decrease). When we simultaneously applied all three GLSOP recommendations, estimated prey‐fish abundance consistently decreased (‐8.8 to ‐16.0%) across reservoirs. Collectively, our findings suggest the need for incorporation of several GLSOP data‐analysis procedures into protocols developed for shallow, target‐rich ecosystems, such as Ohio reservoirs. By doing so, more precise estimates of fish abundance can be generated to the benefit of fishery management.

How individual and relative size affect participation in territorial defense and cortisol levels in a social fish

Isaac Y. Ligocki  Ryan L. Earley  Ian M. Hamilton. 2019.


For many species, behaviors such as territory defense and parental care are energetically costly, but are nonetheless can provide substantial fitness gains. In systems in which both parents provide parental care, each of the parents benefits from exhibiting (or having their partner exhibit) these behaviors. However, in many cases, costs and benefits differ between parents due to factors such as size or sex. Different intruder types may also impose different costs on parents. Predatory intruders might consume offspring, whereas conspecifics might threaten the social status of a parent, or provide benefits as a potential group joiner or mate. Responses to these intrusions may also be associated with variation in individual stress responses. We investigated associations among male and female sizes, and the interaction between these, with defense against conspecific and heterospecific territorial intruders by members of successfully breeding pairs in the cichlid fish Neolamprologus pulcher. We also investigated whether cortisol levels were associated with size or participation in territory defense because each may be a cause or consequence of individual variation in the stress response. We found that females paired with large males performed fewer defensive behaviors than females paired with smaller males. Males paired with relatively large females had higher baseline cortisol levels than those paired with smaller females. Collectively, individual characteristics such as size have consequences for each individual's behavior, and also influence the behavior, and endocrine state of social partners.

Integrating life history traits into predictive phylogeography

Jack Sullivan,  Megan L. Smith,  Anahí Espíndola,  Megan Ruffley,  Andrew Rankin, David Tank,  Bryan Carstens. 2019.


Predictive phylogeography seeks to aggregate genetic, environmental and taxonomic data from multiple species in order to make predictions about unsampled taxa using machine‐learning techniques such as Random Forests. To date, organismal trait data have infrequently been incorporated into predictive frameworks due to difficulties inherent to the scoring of trait data across a taxonomically broad set of taxa. We refine predictive frameworks from two North American systems, the inland temperate rainforests of the Pacific Northwest (PNW) and the Southwestern Aridlands (SWAL), by incorporating a number of organismal trait variables. Our results indicate that incorporating life history traits as predictor variables improves the performance of the supervised machine‐learning approach to predictive phylogeography, especially for the SWAL system, in which predictions made from only taxonomic and climate variables meets only moderate success. In particular, traits related to reproduction (e.g., reproductive mode; clutch size) and trophic level appear to be particularly informative to the predictive framework. Predictive frameworks offer an important mechanism for integration of organismal trait, environmental data, and genetic data in phylogeographic studies.

Space Use of Predatory Larval Dragonflies and Tadpole Prey in Response to Chemical Cues of Predation

TA Brown, ME Fraker, SA Ludsin. 2019. The American Midland Naturalist, 181(1):53-63.


Chemical cues are frequently a key source of information to aquatic organisms. Both predators (kairomones digestive metabolites) and prey (alarm and damage-released cues) may generate chemical cues during their interactions, and different cue types can have different informational values. How predators and prey use the information from chemical cues to make spatial movement decisions influences both their direct interaction rates and their interactions with other species. We measured the spatial response of predatory larval dragonflies (Anax junius) and predator-naïve green frog (Lithobates clamitans) tadpoles exposed to several types of chemical cues using experimental mesocosms. We found tadpoles only responded with spatial avoidance when exposed to both Anax kairomones and conspecific alarm cues together, whereas Anax did not exhibit consistent spatial responses to any cue type. Our results suggest tadpole prey selectively respond to environmental information from chemical cues (possibly to minimize costly antipredator behavior due to responding to insufficient information or reflecting a need for associative learning). They also show predatory dragonflies may use nonchemical information to make space use decisions (possibly due to inability to detect the same chemical cues as tadpoles).

Lack of strategic service provisioning by Pederson’s cleaner shrimp (Ancylomenes pedersoni) highlights independent evolution of cleaning behaviors between ocean basins

Benjamin M. Titus, Marymegan Daly, Clayton Vondriska, Ian Hamilton & Dan A. Exton. 2019. Scientific Reports volume 9, Article number: 629. DOI:


Marine cleaning interactions have been useful model systems for exploring evolutionary game theory and explaining the stability of mutualism. In the Indo-Pacific, cleaner organisms will occasionally “cheat” and remove live tissue, clients use partner control mechanisms to maintain cleaner honesty, and cleaners strategically increase service quality for predatory clients that can “punish” more severely. The extent to which reef communities in the Caribbean have evolved similar strategies for maintaining the stability of these symbioses is less clear. Here we study the strategic service provisioning in Pederson’s cleaner shrimp (Ancylomenes pedersoni) on Caribbean coral reefs. In the Gulf of Honduras, we use video observations to analyze >1000 cleaning interactions and record >850 incidents of cheating. We demonstrate that A. pedersoni cheat frequently and do not vary their service quality based on client trophic position or cleaner shrimp group size. As a direct analog to the cleaner shrimp A. longicarpus in the Indo-Pacific, our study highlights that although cleaning interactions in both ocean basins are ecologically analogous and result in parasite removal, the strategic behaviors that mediate these interactions have evolved independently in cleaner shrimps.