University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Papers in Entomology Museum, University of Nebraska State 2013 Floral associations of cyclocephaline scarab beetles Matthew Robert Moore Wichita State University Mary Liz Jameson Wichita State University, [email protected] Follow this and additional works at: http://digitalcommons.unl.edu/entomologypapers Part of the Entomology Commons Moore, Matthew Robert and Jameson, Mary Liz, "Floral associations of cyclocephaline scarab beetles" (2013). Papers in Entomology. 151. http://digitalcommons.unl.edu/entomologypapers/151 This Article is brought to you for free and open access by the Museum, University of Nebraska State at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Papers in Entomology by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. Journal of Insect Science: Vol. 13 | Article 100 Moore and Jameson Floral associations of cyclocephaline scarab beetles Matthew Robert Moorea* and Mary Liz Jamesonb Wichita State University, Department of Biological Sciences, 1845 Fairmount, Wichita, KS, USA 67260-0026 Abstract The scarab beetle tribe Cyclocephalini (Coleoptera: Scarabaeidae: Dynastinae) is the second larg- est tribe of rhinoceros beetles, with nearly 500 described species. This diverse group is most closely associated with early diverging angiosperm groups (the family Nymphaeaceae, magnoliid clade, and monocots), where they feed, mate, and receive the benefit of thermal rewards from the host plant. Cyclocephaline floral association data have never been synthesized, and a comprehen- sive review of this ecological interaction was necessary to promote research by updating nomenclature, identifying inconsistencies in the data, and reporting previously unpublished data. Based on the most specific data, at least 97 cyclocephaline beetle species have been reported from the flowers of 58 plant genera representing 17 families and 15 orders. Thirteen new cy- clocephaline floral associations are reported herein. Six cyclocephaline and 25 plant synonyms were reported in the literature and on beetle voucher specimen labels, and these were updated to reflect current nomenclature. The valid names of three unavailable plant host names were identi- fied. We review the cyclocephaline floral associations with respect to inferred relationships of angiosperm orders. Ten genera of cyclocephaline beetles have been recorded from flowers of ear- ly diverging angiosperm groups. In contrast, only one genus, Cyclocephala, has been recorded from dicot flowers. Cyclocephaline visitation of dicot flowers is limited to the New World, and it is unknown whether this is evolutionary meaningful or the result of sampling bias and incomplete data. The most important areas for future research include: 1) elucidating the factors that attract cyclocephalines to flowers including floral scent chemistry and thermogenesis, 2) determining whether cyclocephaline dicot visitation is truly limited to the New World, and 3) inferring evolu- tionary relationships within the Cyclocephalini to rigorously test vicarance hypotheses, host plant shifts, and mutualisms with angiosperms. Journal of Insect Science | http://www.insectscience.org 1 Journal of Insect Science: Vol. 13 | Article 100 Moore and Jameson Keywords: Cantharophily, Scarabaeidae, Dynastinae, Araceae, Arecaceae, Annonaceae, Nymphaceae Correspondence: a [email protected], b [email protected], *Corresponding author. Editor: Daniela Takiya and Inon Scharf were editor of this paper. Received: 8 July 2012 Accepted: 13 November 2012 Published 1 October 2013 Copyright: This is an open access paper. We use the Creative Commons Attribution 3.0 license that permits unrestricted use, provided that the paper is properly attributed. ISSN: 1536-2442 | Vol. 13, Number 100 Cite this paper as: Moore MR, Jameson ML. 2013. Floral associations of cyclocephaline scarab beetles. Journal of Insect Science 13:100. Available online: http://www.insectscience.org/13.100 clocephaline visitation of dicot flowers is Introduction poorly known and little studied. The Cyclocephalini (Coleoptera: Scarabae- Cyclocephaline floral associations have been idae: Dynastinae) is the second largest reported in journals, books, and monographs rhinoceros beetle tribe, currently containing since the late 18th century. However, the prev- 15 genera and nearly 500 described beetle alence, geographic scope, and biological species (Jameson et al. 2002; Ratcliffe 2003; importance of these records are difficult to Smith 2006). Cyclocephalines have a pan- gauge because publications summarizing cy- tropical distribution, though the majority of clocephaline floral visitation are somewhat the group’s generic and species diversity is dated and report floral visitation only for spe- concentrated in the New World (Ratcliffe cific plant families, geographic areas, or 2003; Ratcliffe and Cave 2006). Most genera vegetation types (Henderson 1986; Gibernau are sexually dimorphic, with males having 2003; Gottsberger and Silberbauer- enlarged protarsal claws and females having Gottsberger 2006; Gibernau 2011). The frag- expanded elytral epipleura (Moore 2012). Cy- mentary nature of these data and the citation clocephalines are important economically and of unpublished observations have hampered ecologically as root pests (larvae) and pollina- the ability to identify floral association trends tors (adults) (Ratcliffe 2003; Ratcliffe and within cyclocephaline genera and species. Paulsen 2008). Adult cyclocephaline beetles can be found within the inflorescences of ear- The phylogeny of the Cyclocephalini was in- ly diverging angiosperm groups (the family vestigated for the first time by Clark (2011), Nymphaeaceae, magnoliid clade, and mono- and the generic-level relationships within the cots; Figure 1) and have been shown to tribe remain an area of active research by M. contribute to pollination in the Annonaceae, R. Moore. Tribal circumscription of the Cy- Araceae, Arecaceae, Cyclanthaceae, Magnoli- clocephalini is subject to change based on aceae, and Nymphaeaceae (Cramer et al. ongoing phylogenetic analyses. This research 1975; Beach 1982; Beach 1984; Young 1986; will provide an evolutionary framework for Young 1988b; Gottsberger 1989; Dieringer et interpreting patterns of floral visitation. Com- al. 1999; Hirthe and Porembski 2003; Maia et pilation and synthesis of a checklist of floral al. 2012). Studies of these interactions indi- associations is needed in order to understand cate that some early diverging angiosperm the ecology of the Cyclocephalini within a groups offer rewards to cyclocephalines in the phylogenetic context. form of mating sites, food, and metabolic boosts associated with floral thermogenicity in This checklist synthesizes data (plant and bee- return for pollination services (Gottsberger tle species, geographic locality, and original 1986; Young 1986; Seymour et al. 2009). Cy- citation) for the floral associations of adult Journal of Insect Science | http://www.insectscience.org 2 Journal of Insect Science: Vol. 13 | Article 100 Moore and Jameson cyclocephaline beetles. Invalid nomenclature unverified plant names were reported accord- in the surveyed literature is identified and cor- ing to the original citation for the floral rected; conflicting data, sources of error, and association, and the name was noted as unre- uncertainty in the data are identified; and un- solved. Occasionally, host plant and beetle published floral association data from species were not assigned an author in the ref- examined voucher specimens are added. The erence for an association. This caused aim of this work is to promote future research problems due to the prevalence of synonyms of these ecological interactions by providing a and homonyms in the plant and insect litera- comprehensive data set of the taxonomic and ture. Resulting ambiguities were rectified to geographic scope of floral visitation for cy- the extent possible and explained in the re- clocephaline beetles. marks column (Appendix 1). Materials and Methods Borrowed specimens of cyclocephaline spe- cies allowed for direct evaluation of species- Literature was surveyed from 1758 (Linnaeus) level identifications that were reported by to 2012. Keyword searches for all cyclocepha- several authors. Particularly, this included line genera (sensu Ratcliffe and Cave 2006; specimens of Cyclocephala sexpunctata Clark 2011) were conducted in the following Laporte (1840) and C. brevis Höhne (1847) databases: BioOne® (www.bioone.org), collected by George Schatz, Helen Young (La BIOSIS Previews® Selva Biological Station, Costa Rica), Alberto (http://apps.webofknowledge.com/), JSTOR Seres, and Nelson Ramirez (Henri Pittier Na- (www.jstor.org), and Biodiversity Heritage tional Park, Venezuela), with floral Library (www.biodiversitylibrary.org). Every association data that were subsequently pub- host plant reference from Pike et al. (1976) lished or unpublished. Identifications of these was checked for floral association data. specimens (or specimen vouchers) were criti- cally examined (Moore 2011). Exemplar All reported cyclocephaline species names material borrowed from the University of Ne- from the literature were verified by referenc- braska State Museum (authoritatively ing the original species description and identified by B. C. Ratcliffe) and monograph- monographic treatments of the Dynastinae ic treatments (Ratcliffe 2003; Ratcliffe and (Endrödi 1985;