Kevin Burgio and Veronica Bueno, currently graduate students in EEB, joined EEB alumnus Colin Carlson and others in reporting their study “Parasite biodiversity faces extinction and redistribution in a changing climate” in Science Advances. The study rests on data for countless samples preserved in natural history collections including the Biodiversity Research Collection EEB at UCONN.

Carlson, C.J., Burgio, K.R., Dougherty, E.R., Phillips, A.J., Bueno, V.M., Clements, C.F., Castaldo, G., Dallas, T.A., Cizauskas, C.A., Cumming, G.S. and Doña, J., 2017. Parasite biodiversity faces extinction and redistribution in a changing climate. Science Advances 3(9), p.e1602422.

The abstract reads: Climate change is a well-documented driver of both wildlife extinction and disease emergence, but the negative impacts of climate change on parasite diversity are undocumented. We compiled the most comprehensive spatially explicit data set available for parasites, projected range shifts in a changing climate, and estimated extinction rates for eight major parasite clades. On the basis of 53,133 occurrences capturing the geographic ranges of 457 parasite species, conservative model projections suggest that 5 to 10% of these species are committed to extinction by 2070 from climate-driven habitat loss alone. We find no evidence that parasites with zoonotic potential have a significantly higher potential to gain range in a changing climate, but we do find that ectoparasites (especially ticks) fare disproportionately worse than endoparasites. Accounting for host-driven coextinctions, models predict that up to 30% of parasitic worms are committed to extinction, driven by a combination of direct and indirect pressures. Despite high local extinction rates, parasite richness could still increase by an order of magnitude in some places, because species successfully tracking climate change invade temperate ecosystems and replace native species with unpredictable ecological consequences.

Drs. Janine Caira and Kirsten Jensen edited a special volume of the University of Kansas, Museum of Natural History publication entitled “Tapeworms from the vertebrate bowels of the earth” presenting the outcome of their NSF funded Planetary Biodiversity Inventory project. This publication is open source (available through the above link).

The preface reads: This document is organized into 22 peer-reviewed chapters. Each of the chapters focuses on an individual cestode group, begins with the status of knowledge of the group prior to the inception of the PBI project, and ends with an assessment of the current understanding of the group. In each case, diversity, classification, morphology, phylogenetic relationships, host associations, and geographic distribution are addressed. In all but one case, each chapter includes a list of valid taxa. Synonyms have not generally been listed; this was determined to be beyond the scope of the project given the immensity of such lists for some groups.  With over 3,000 valid species, the generation of a list of species for the Cyclophyllidea was also determined to be beyond the scope of this project. However, a list of valid higher taxa is provided. Each of the 19 cestode orders is addressed alphabetically in separate chapters with two exceptions. The Mesocestoididae are treated as a family in the Cyclophyllidea. Although evidence supporting recognition of the former as an independent order is mounting, the case remains to be formally made based on more detailed investigations of this enigmatic group of mammal parasites. The Onchoproteocephalidea are the second exception. So as to emphasize the dual nature of the host associations and scolex morphology of its members, the freshwater fish-parasitizing taxa (formerly assigned to the order Proteocephalidea) are treated in a chapter as the Onchoproteocephalidea I separately from the taxa that parasitize elasmobranchs, which are treated as the Onchoproteocephalidea II. Use of quotation marks around taxon names (e.g., the order “Tetraphyllidea”) is to remind readers of the definitively non-monophyletic nature of these groups. The first and last chapters are more synthetic in nature. The first chapter provides an overview of the results of the project both in terms of its Intellectual Merit and Broader Impact elements (to use NSF terminology). The final chapter provides a molecular framework for the phylogenetic relationships among the cestodes as they are understood at the end of the PBI project. The final chapter also describes the molecular methods and taxon sampling employed to achieve that framework. This Special Issue concludes with an Appendix listing the more than 220 publications directly resulting from project efforts, all of which cite the PBI award (NSF DEB Nos. 0818696 and 0818823).

Dr. Don Les, director of the CONN herbarium published his first treatment of the aquatic plants of North America: Aquatic Dicotyledons of North America: Ecology, Life History, and Systematics. Congratulations.

Summary: Aquatic Dicotyledons of North America: Ecology, Life History, and Systematics brings together a wealth of information on the natural history, ecology, and systematics of North American aquatic plants. Most books on aquatic plants have a taxonomic focus and are intended primarily for identification. Instead, this book provides a comprehensive overview of the biology of major aquatic species by compiling information from numerous sources that lie scattered among the primary literature, herbarium databases, and other reference materials. Included dicotyledon species are those having an obligate (OBL) wetland status, a designation used in the USACE National Wetland Plant List. Recent phylogenetic analyses are incorporated and rationale is provided for interpreting this information with respect to species relationships. This diverse assemblage of information will be useful to a wide range of interests including academic researchers, wildlife managers, students, and virtually anyone interested in the natural history of aquatic and wetland plants. Although focusing specifically on North America, the cosmopolitan distribution of many aquatic plants should make this an attractive text to people working virtually anywhere outside of the region as well. This book is an essential resource for assisting with wetland delineation.

 

The exhibit on the life of army ants and their guests has opened in the Biology/Physics building (see UCONN today).  The public opening drew close to 300 visitors on Sunday, who discovered the giant ant and its eight guests, the 100 photographs illustrating the tiny and unique guests, and actual specimens displayed under microscopes and engaged in activities to earn and collect the guest buttons. Many guests toured the Biodiversity Research Collection, guided by EEB graduate students highlighting its richness and scientific value.  Visit the AAGC Facebook book page for more news on the curation of and activities related to the AAGC.

John Silander and colleagues (all EEB alumni) published their research on the effects of climate change on invasive species in New England in the Proceedings of the National Academy of Sciences. Vouchers for their research are deposited in the CONN herbarium.

Citation: Merow, C., S.T. Bois, J.M. Allen, Y. Xie & J.A. Silander. 2017. Climate change both facilitates and inhibits invasive plant ranges in New England. Proceedings of the National Academy of Sciences 114(16): E3276-E3284. pdf

The significance of the study: Invasive species are often expected to benefit from novel conditions encountered with global change. Our range models based on demography show that invasive Alliaria petiolata (garlic mustard) may have much lower establishment in New England under future climate, despite prolific success under current climate, whereas other invasive and native plants may expand their ranges. Forecasts suggest that management should focus on inhibiting northward spread of A. petiolata into unoccupied areas and understanding source–sink population dynamics and how community dynamics might respond to loss of A. petiolata (it modifies soil properties). Our methods illustrate inadequacy of current approaches to forecasting invasions in progress, which are based on correlations between species’ occurrence and environment and illustrate critical need for mechanistic studies.

Nora Mitchell, who defended her dissertation this week, lead a study on the radiation of the charismatic South African genus Protea L., which appeared in the American Journal of Botany.

Mitchell N., P.O. Lewis, E.M. Lemmon, A.R. Lemmon & K.E. Holsinger. 2017. Anchored phylogenomics improves the resolution of evolutionary relationships in the rapid radiation of Protea L. American Journal of Botany 104: 102–115. pdf

The abstract reads: PREMISE OF THE STUDY: Estimating phylogenetic relationships in relatively recent evolutionary radiations is challenging, especially if short branches associated with recent divergence result in multiple gene tree histories. We combine anchored enrichment next-generation sequencing with species tree analyses to produce a robust estimate of phylogenetic relationships in the genus Protea (Proteaceae), an iconic radiation in South Africa.

METHODS: We sampled multiple individuals within 59 out of 112 species of Protea and 6 outgroup species for a total of 163 individuals, and obtained sequences for 498 low-copy, orthologous nuclear loci using anchored phylogenomics. We compare several approaches for building species trees, and explore gene tree–species tree discrepancies to determine whether poor phylogenetic resolution reflects a lack of informative sites, incomplete lineage sorting, or hybridization.

KEY RESULTS: Phylogenetic estimates from species tree approaches are similar to one another and recover previously well-supported clades within Protea, in addition to providing well-supported phylogenetic hypotheses for previously poorly resolved intrageneric relationships. Individual gene trees are markedly different from one another and from species trees. Nonetheless, analyses indicate that differences among gene trees occur primarily concerning clades supported by short branches.

CONCLUSIONS: Species tree methods using hundreds of nuclear loci provided strong support for many previously unresolved relationships in the radiation of the genus Protea. In cases where support for particular relationships remains low, these appear to arise from few informative sites and lack of information rather than strongly supported disagreement among gene trees.

Colleagues in California described a new species of moss, and several types (i.e., specimen upon which the original description is based) are deposited in the CONN herbarium, further enhancing its significance as a biodiversity repository.

Toren, D. R., K. M. Kellman, and J. R. Shevock. Archidium crassicostatum (Archidiaceae), a new and long-overlooked species from California, USA. Madroño 63: 348–352. pdf

Abstract: Archidium crassicostatum D.R. Toren, Kellman & Shevock is described and illustrated, and is currently known from two counties from California. It appears to be the sole species of the genus from the state and is well marked by its exceptionally wide costa, which can occupy as much as one third the width of the leaf base. Previous reports of Archidium alternifolium (Dicks. ex Hedw.) Schimp. and A. donnellii Austin from California are actually A. crassicostatum. Details of habitat, ecology, and distribution are given and morphological distinctions among similar-looking but unrelated taxa are discussed.

 

Undergraduate students working in the G.S. Torrey Herbarium have finished a 3-year project that involved creating high-resolution digital images of nearly 33,000 specimens donated by the Delta Institute in Maine. Most of the specimens were collected by members of the Hadwen Botanical Club at Clark University in Worcester, Massachusetts, in the 1930s and 1940s. The botanists at the time were attempting to collect one specimen of every species in every town in Worcester County, which is the largest county in Massachusetts. Now that all of the images have been created, the UConn students have begun using the images to enter information about the specimens – when and where they were collected, for instance – into a database that already contains information on all other specimens in the herbarium (about 210,000 specimens in all). The database makes specimen information available online to botanists all over the world so the information can be used in research on plant systematics, variation within plant species, changes in flowering time and other subjects

Two new publications from the Caira lab on parasites, with vouchers deposited in the BRC collections:

1. Bernot J. P., J.N. Caira & M. Pickering. 2016. Diversity, phylogenetic relationships and host associations of Calliobothrium and Symcallio (Cestoda:‘Tetraphyllidea’) parasitising triakid sharks. Invertebrate Systematics 30: 616–634. pdf

Abstract reads: The laciniate, relatively large-bodied tetraphyllidean tapeworm genus Calliobothrium van Beneden, 1850 parasitises triakid sharks with all but one species found parasitising sharks of the genus Mustelus Linck, 1790. Historically, species of this genus were thought to exhibit a relaxed degree of host specificity relative to species of their sister genus Symcallio Bernot, Caira, & Pickering, 2015. However, several more recent studies have begun to question this difference and, in particular, the conspecificity of specimens identified as the types species, C. verticillatum (Rudolphi, 1819) van Beneden, 1850, from multiple host species. Our results suggest that diversity in the genus Calliobothrium has been under-reported. To explore this situation, specimens previously identified as C. verticillatum were collected from Mustelus asterias Cloquet, 1819 off the United Kingdom and Mustelus canis (Mitchell, 1815) off Connecticut, USA; these sharks each were found to host distinct species both of which are described here. Mustelus asterias was also confirmed to host Symcallio leuckarti (van Beneden, 1850) Bernot, Caira & Pickering, 2015, which is redescribed. In combination with newly collected material from Mustelus palumbes Smith, 1957 off South Africa and data available from GenBank, molecular phylogenetic analyses based on 28S rDNA data for four of the seven known species of Calliobothrium, including both new species and five of the 11 known species of Symcallio, were conducted. The resulting phylogeny supports the mutual monophyly of the two genera, which are readily distinguished based on whether they exhibit proglottid laciniations, and supports subclades of Symcallio with and without hook accessory pieces. These subclades of Symcallio appear to exhibit an intriguing congruence with two known subclades of their host genus, Mustelus.

 

2. Koontz A. & J.N. Caira. 2016. Emendation of Carpobothrium (“Tetraphyllidea”) from Bamboosharks (Orectolobiformes: Hemiscyliidae) with redescription of Carpobothrium chiloscyllii and description of a new species from Borneo. Comparative Parasitology 83: 149–161. pdf

Abstract reads: Collection of new material from the bamboosharks Chiloscyllium indicum (Gmelin, 1789) and Chiloscyllium hasseltii Bleeker, 1852, from Indonesian and Malaysian Borneo prompted reevalutation of the identity and host associations of the cestode genus Carpobothrium Shipley and Hornell, 1906. Light microscopical examination of whole mounts, histological sections, and egg preparations, in combination with scanning electron microscopy of scoleces, led to redescription of the type species Carpobothrium chiloscyllii Shipley and Hornell, 1906, from Ch. indicum, as well as description of a new species from Ch. hasseltii. The proglottid anatomy of C. chiloscyllii is described for the first time. The genus was confirmed to exhibit pouch-like bothridia with relatively small anterior and posterior flaps that have a tendency to retract into the bothridial pouches, testes that are entirely pre‐poral, a uterus that extends only to the cirrus sac, and a vas deferens that coils posterior to the cirrus sac. Although not previously reported for the genus, both species were determined to possess an apical sucker on the anterior margin of the anterior bothridial flap. The posterior coiling of the vas deferens allowed free gravid proglottids of the new Carpobothrium species to be distinguished from those of Yorkeria Southwell, 1927, and to determine that, while eggs of the former are spherical with bipolar filaments, those of the latter are spindle-shaped with unipolar filaments. Examination of some of Southwell’s material identified as C. chiloscyllii from the batoid hosts Urogymnus asperrimus Bloch and Schneider, 1801 and Rhynchobatus djeddensis Forsskål, 1775, in Sri Lanka, confirmed evidence from molecular work suggesting that these cestodes, which also bear pouch-like bothridia, represent a distinct group of cestodes from those parasitizing bamboosharks. This work both confirms the association of Carpobothrium species with sharks of the genus Chiloscyllium Müller and Henle, 1837, and paves the way for establishment of a novel genus for the taxa parasitizing batoids