The Society for Integrative and Comparative Biology with the American Microscopical Society The Crustacean Society SICB 2020 ABSTRACT BOOK January 3-7, 2020 JW Marriott Austin • Austin, TX Abstract Book SICB does not assume responsibility for any inconsistencies or errors in the abstracts for contributed paper and poster presentations. We regret any possible omissions, changes and/ or additions not reflected in this abstract book. SICB 2020 Annual Meeting Abstracts 127-1 AARON GOODMAN, AMG*; LAUREN ESPOSITO, LAE; 56-5 ABBOTT, EA*; DIXON, GB; MATZ, MV; University of California Academy of Sciences, California Academy of Sciences ; Texas; [email protected] [email protected] Disentangling coral stress and bleaching responses by comparing Spatial and Ecological Niche Partitioning in Congeneric Scorpions gene expression in symbiotic partners Species in the scorpion genus Centruroides Marx, 1890 (Scorpiones: Coral bleaching—the disruption of the symbiosis between a coral Buthidae) are good candidates to study ecological niche partitioning host and its endosymbiotic algae—is associated with environmental due to their habitat plasticity, widespread geographic distribution, stressors. However, the molecular processes are not well understood, and presence of cryptic species. Currently, three species belonging to and no studies have disentangled the transcriptional bleaching three subgroups of Centruroides are distributed along the Isthmus of response from the stress response. In order to characterize general Tehuantepec in southern Mexico, presenting a rare opportunity to stress response, specific stress responses, and the bleaching response, study niche partitioning within a single genus. We examined the we isolated host and symbiont RNA from fragments of Acropora environmental, substrate, and habitat preferences of Centruroides millepora which were exposed to 5 different stress treatments. We flavopictus, Pocock, 1890, Centruroides gracilis, Latreille 1904, and hypothesize that under stress conditions, the coral host, and not the Centruroides rileyi, Sissom 1995 within La Estación Biología Los symbionts, become stressed. If this hypothesis is correct we predict Tuxtlas west of the Isthmus of Tehuantepec. Our results demonstrate that the host may upregulate genes involved in oxidative stress, habitat partitioning occurs along humidity, temperature, and immune response, heat shock proteins, or lipid metabolism; we also elevational gradients, with C. gracilis preferring habitats of low expect that the symbiont would upregulate genes involved in growth humidity and high temperature and is predominantly found on the and uptake of nutrients. Additionally, it is unknown whether the host substrate in human-mediated habitats, ""C. flavopictus"" exhibited a or the symbiont initiates bleaching. Because symbionts are larger range of humidity and temperature preferences but was found horizontally acquired, their success is not linked to the survival of the within secondary and primary forest, and C. rileyi had the greatest host. Thus, we hypothesize that when the host becomes stressed, the specificity of low temperature and high humidity on trees within symbionts initiate bleaching. To capture the bleaching response, primary forest. Furthermore, C. rileyi was found significantly higher ambient conditions were reestablished after treatments and samples in trees than C. flavopictus. This study represents the first example of of RNA were taken at multiple time points, between 8-16 hours after niche partitioning within a genus of arachnid, and the first description the treatment. The RNA was sequenced with tag-based RNA of the ecological niche in an arboreal-specialist scorpion. sequencing and the data were analyzed using DESeq and WGCNA. If the symbionts initiate bleaching, we expect that the expression profile of the symbionts will resemble symbionts in the free-living state—such as upregulation of genes involved in sexual reproduction and motility. Conversely, if the host initiates bleaching we expect to upregulation of genes involved in immune response, exocytosis, or nutrient transport. P1-56 ABBOTT, CP*; LOCKWOOD, R; SUES, H-D; HUNT, G; P3-2 ABDULELAH, SA*; CRILE, KG; ALMOUSELI, A; AWALI, ANGIELCZYK, KD; The University of Chicago, Chicago, IL, S; TUTWILER, AY; TIEN, EA; MANZO, VJ; HADEED, MN; William & Mary, Williamsburg, VA, Smithsonian Institution, BELANGER, RM; University of Detroit Mercy; Washington, DC, Smithsonian Institution, Washington, DC, The [email protected] Field Museum, Chicago, IL; [email protected] DNA damage in the cells of lateral antennules of crayfish ( How useful are extant tetrapods as analogues for non-mammalian Faxonius virilis) is increased following exposure to synapsid posture? environmentally relevant concentrations of atrazine Reconstructing non-mammalian synapsid posture usually takes one Atrazine (ATR) is an herbicide commonly applied in agricultural of two approaches. One approach models range of motion and regions in the Midwestern United States. Excess ATR can enter muscle moment arms from fossils, and another method compares nearby aquatic environments through run-off and seepage, causing fossils to extant tetrapod analogues. The former method is ATR concentrations to increase and placing non-target aquatic constrained by how well body fossils reflect in vivo biomechanics, organisms, like crayfish, at risk of ATR exposure. It has been shown while the latter is limited by the relevance of extant analogues to that acute exposure to 80 ppb (µg/L) ATR can cause chemosensory fossil synapsids. Non-mammalian synapsids lack both extant deficits in crayfish. Knowing that ATR causes impairments on representatives and a tight phylogenetic bracket. The only extant olfactory-mediated behaviors, our aim for this study was to synapsids are mammals, which are highly derived and disparate determine the effects of ATR in olfactory sensory neurons, located in compared to most fossil synapsids. Extant reptilian and amphibian the lateral antennules of crayfish. We exposed crayfish to analogues also possess derived morphologies compared to their environmentally relevant concentrations of ATR (0, 10, 40, 80, 100 extinct relatives, despite superficially "primitive” postures. Does the and 300 ppb) for 10 days. Following exposures, the distal portion of high phylogenetic and morphological disparity of these analogues the lateral antennule was cryosectioned, and a TdT mediated dUTP impact their usefulness? We collected long bone and girdle nick-end labelling (TUNEL) assay was done in order to determine if dimensions from skeletal material for of 45 extant mammal, reptile, cells in the lateral antennules had DNA damage. We found a and amphibian taxa, and compared these data with analogous significant increase of TUNEL-positive cells as atrazine increased measurements from Diasparactus, Ophiacodon, Dimetrodon, and above 10 ppb. The data that we obtained showed that DNA damage Aulacephalodon. We used principal component analysis to visualize is caused in the cells of lateral antennules, including olfactory the distribution of the sampled taxa in morphospace, and sensory neurons, which ultimately compromises the chemosensory phylogenetic flexible discriminant analysis to explore categorical abilities of crayfish. This is concerning as crayfish rely heavily on estimates of synapsid posture compared to traditional extant chemosensory abilities for many aspects of their lives. locomotor grades. Results indicate that fossil synapsids lack informative locomotor analogues among extant tetrapods. Furthermore, our results suggest that the traditional sprawling-upright dichotomy not only masks the continuum of tetrapod posture, but also ignores phylogenetic and physical constraints relevant to their locomotor habits. January 3-7, 2020, Austin, TX 1 SICB 2020 Annual Meeting Abstracts P2-69 ABERNATHY, A.L*; KLAR, E.A; JORDAN, C.H; JOSHI, 58-5 ABZHANOV, A; Imperial College London and Natural History M.M; NEWBREY, M.G; Columbus State University; Museum, United Kingdom; [email protected] [email protected] Phylogenetic Principles and Morphogenetic Mechanisms for Comparison of intersex severity between two types of histological Evolvability in Adaptive Radiations sections using testes of Largemouth Bass (Micropterus salmoides) Understanding the origins of morphological variation is one of the and Spotted Bass (M. punctulatus) from the Chattahoochee River, chief challenges to the modern biological sciences. Cranial diversity Georgia in vertebrates is a particularly inviting research topic as animal heads Previous studies have not adequately quantified or compared the and faces show many dramatic and unique adaptive features which severity of feminization (intersex) between cross and longitudinal reflect their natural history. We aim to reveal molecular mechanisms sections of testes. In previous studies, intersex severity was ranked underlying evolutionary processes that generate such morphological on a scale of 0-4: 0 = no oocytes, 1 = one oocyte, 2 = more than one variation. To this purpose, we employ a synergistic combination of oocyte, 3 = a cluster of oocytes, 4 = multiple clusters of oocytes. This geometric morphometrics, comparative molecular embryology and ranking system is ineffective for assessing intersex severity with high functional experimentation methods to trace cranial evolution in counts of oocytes. Our goal was to compare the severity of intersex reptiles, birds and mammals, some of the