General biology II, introduction to research, evolution, comparative vertebrate anatomy
Discovery, Description, and Evolution of Parasites
Parasitism is arguably the most common mode of life on earth. It has evolved dozens (if not hundreds) of times within the animal kingdom. Platyhelminths, or flatworms, are a diverse group of invertebrates composed of some free-living groups (e.g., planarians) and some parasitic groups (e.g., flukes and tapeworms). My primary research interests focus on the discovery, description, and evolution of a group of tapeworms, the Lecanicephalidea. Lecanicephalideans, as adults, are intestinal parasites specific to elasmobranchs (e.g., sharks and rays). The vast majority of lecanicephalideans are found in the spiral intestine of rays, but a few species have been found in sharks. This group of tapeworms exhibits a high degree of specificity, meaning that one tapeworm species likely parasitizes only a single species of ray or shark. This suggests long co-evolutionary relationships between parasite and host.
Most of my research involves discovery and description of new lecanicephalidean species or revisionary taxonomy of previously described species. In the past decade more than 30 new species have been described, primarily from rays in the Austral-Asian region. It is estimated that another 50-100 (or more!) new species are yet to be discovered. This host-parasite system provides ample opportunity for students to develop independent research projects on discovery and description of biodiversity, but also to develop broader long-term questions about the evolution and life-history patterns of these parasites.
Additional research experience and interests include similar discovery and diversity studies of protozoan parasites, gregarines (Phylum Apicomplexa) and their insect hosts. Gregarines are ubiquitous single-celled parasites of insects and other invertebrates (e.g., polychaetes, shrimp, etc.). Although they are related to human pathogens, such as the causative agents of malaria and cryptosporidiosis, they are relatively non-pathogenic to their invertebrate hosts. I have conducted biogeographical studies of gregarines parasitizing closely related species of damselflies to address questions relating to parasite species distribution, host-specificity, and ecological specificity. Gregarine research projects provide excellent opportunities for undergraduate students at Rockhurst University to be involved in the entire research process from field-collections and specimen preparation to data collection and analyses, and ultimately presentation or publication of results.
Jensen, K., J.N. Caira, J.J. Cielocha, D.T.J. Littlewood, and A. Waeschenbach. 2016. When proglottids and scoleces conflict: phylogenetic relationships and a family-level classification of the Lecanicephalidea (Platyhelminthes: Cestoda). International Journal for Parasitology 46: 291–310. DOI: 10.1016/j.ijpara.2016.02.002.
Cielocha, J. J., K. Jensen, & J. N. Caira. 2014. Floriparicapitus, a new genus of lecanicephalidean tapeworm (Cestoda) from sawfishes (Pristidae) and guitarfishes (Rhinobatidae) in the Indo-West Pacific. Journal of Parasitology 100: 485–499. DOI: 10.1645/13.468.1.
Cielocha, J. J., A. Yoneva, M. E. Cantino, S. Daniels, & K. Jensen. 2013. Investigation of sperm ultrastructure of Adelobothrium sp. (Cestoda: Lecanicephalidea). Invertebrate Biology 132: 315–325. DOI: 10.1111/ivb.12036.
Cielocha, J. J. & K. Jensen. 2013. Stoibocephalum n. gen. (Cestoda: Lecanicephalidea) from the sharkray, Rhina ancylostoma (Elasmobranchii: Rhinopristiformes), from northern Australia. Zootaxa 3626 (4): 558–568. DOI: 10.11646%2Fzootaxa.3626.4.9.
Borucinska, J. D., J. J. Cielocha, & K. Jensen. 2013. The parasite-host interface in the zonetail butterfly ray Gymnura zonura, infected with Hexacanalis folifer (Cestoda: Lecanicephalidea). Journal of Fish Diseases 36: 1–8. DOI:10.1111/j.1365-2761.2012.01408.x.
Cielocha, J. J. & K. Jensen. 2011. A revision of Hexacanalis Perrenoud, 1931 (Cestoda: Lecanicephalidea) and description of H. folifer from the zonetail butterfly ray, Gymnura zonura (Bleeker) (Rajiformes: Gymnuridae). Systematic Parasitology 79(1): 1–16. DOI 10.1007/s11230-011-9291-1.
Cielocha, J. J., T. J. Cook, & R. E. Clopton. 2011. Host utilization and distribution of nubenocephalid gregarines (Eugregarinorida: Actinocephalidae) parasitizing Argia spp. (Odonata: Zygoptera) in the central United States. Comparative Parasitology 78(1):152–160. DOI: 10.1654/4459.1.
Clopton, R. E., T. J. Cook, & J. J. Cielocha. 2010. Nubenocephalus nickoli n. sp. and Nubenocephalus xunantunichensis n. sp. (Apicomplexa: Eugregarinida: Actinocephalidae) parasitizing damselflies (Odonata: Zygoptera) in Belize, Central America. Comparative Parasitology 77(2): 125–136. DOI: 10.1654/4438.1.
Hays, J. J., R. E. Clopton, T. J. Cook, & J. L. Cook. 2007. Revision of the genus Nubenocephalus and description of Nubenocephalus secundus n. sp. (Apicomplexa: Actinocephalidae) parasitizing adults of Argia sedula (Odonata: Zygoptera: Coenagrionidae) in the primitive Texas Big Thicket, U.S.A. Comparative Parasitology 74(2): 286–293. DOI: 10.1654/4287.1.
Clopton, R. E. & J. J. Hays. 2006. Revision of the genus Protomagalhaensia and description of Protomagalhaensia wolfi n. comb. (Apicomplexa: Eugregarinida: Hirmocystidae) and Leidyana haasi n. comb. (Apicomplexa: Eugregarinida: Leidyanidae) parasitizing the Lobster Cockroach, Nauphoeta cinerea (Dictyoptera: Blaberidae). Comparative Parasitology 73(2): 137–156. DOI: 10.1654/4241.1.
Hays, J. J., R.E. Clopton, D.L. Cappaert, & D.R. Smitley. 2004. Revision of the genus Stictospora and description of Stictospora villani, n. sp. (Apicomplexa: Eugregarinida: Actinocephalidae) from larvae of the Japanese Beetle, Popillia japonica (Coleoptera: Scarabaeidae), in Michigan. Journal of Parasitology 90(6): 1450–1456. DOI: 10.1645/GE-345R.