Moving Toward Species-Level Phylogeny Using
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ZOBODAT - www.zobodat.at Zoologisch-Botanische Datenbank/Zoological-Botanical Database Digitale Literatur/Digital Literature Zeitschrift/Journal: Arthropod Systematics and Phylogeny Jahr/Year: 2014 Band/Volume: 72 Autor(en)/Author(s): Kjer Karl M., Zhou Xin, Frandsen Paul B., Thomas Jessica A., Blahnik Roger J. Artikel/Article: Moving toward species-level phylogeny using ribosomal DNA and COI barcodes: an example from the diverse caddisfly genus Chimarra (Trichoptera: Philopotamidae) 345-354 72 (3): 345 – 354 19.12.2014 © Senckenberg Gesellschaft für Naturforschung, 2014. Moving toward species-level phylogeny using ribosomal DNA and COI barcodes: an example from the diverse caddisfly genus Chimarra (Trichoptera: Philopotamidae) Karl M. Kjer 1, Xin Zhou 2, Paul B. Frandsen 3, Jessica A. Thomas 4 & Roger J. Blahnik *, 5 1 Rutgers University, New Brunswick, NJ, USA, Department of Ecology, Evolution, and Natural Resources. 14 College Farm Rd. New Bruns- wick, NJ 08901; Karl Kjer [[email protected]] — 2 BGI-Shenzhen, Bldg.11, 2nd Floor, Beishan Industrial Zone, Beishan Road, Yantian Dis- trict, Shenzhen, Guangdong Province, China 518083; Xin Zhou [[email protected]] — 3 Rutgers University, New Brunswick, NJ, USA, Department of Entomology. 93 Lipman Drive, New Brunswick, NJ 08901; Paul Frandsen [[email protected]] — 4 Department of Biology, University of York, Heslington, York, United Kingdom, YO10 5DD; Jessica Thomas [[email protected]] — 5 University of Min- nesota, Department of Entomology, 1980 Folwell Ave. St. Paul MN 55108; Roger Blahnik * [[email protected]] — * Corresponding author Accepted 17.vii.2014. Published online at www.senckenberg.de/arthropod-systematics on 12.xii.2014. Abstract The genus Chimarra (Trichoptera, Philopotamidae) is a cosmopolitan genus with over 700 species. The taxonomic history of Chimarra is discussed, with reference to how large genera are best subdivided. We also examine the phylogenetic utility of the COI “barcode” fragment and find it to be phylogenetically useful, within limits. Adding a single fragment of nuclear rRNA (specifically the 28S D2 region) converts the barcode hypothesis into a strongly supported phylogeny that is corroborated by a morphologically derived subgeneric classification. This suggests that a simple two gene dataset could be combined with morphological data in order to rapidly and inexpensively include a molecular component to generic revisions. We confirm the monophyly of Chimarra (Chimarra), C. (Curgia), C. (Otarrha), and core C. (Chimarrita). The C. (C.) tsudai group is also recovered. We make use of web-based materials, including the BOLD website (http:// www.boldsystems.org/), and keyhole markup language files (.kml format), which permit specimen data to be viewed on Google Earth. We suggest that static phylogenies presented in print could be dynamically updated with the use of these web materials. Key words Trichoptera, Chimarra, COI, barcode, keyhole markup language, phylogenetic utility, generic taxonomy. 1. Introduction The genus Chimarra Stephens, 1829 (Philopotamidae: is nearly cosmopolitan, although only marginally repre Chimarrinae), with over 780 described species (WAHL- sented in Europe (by C. marginata (Linnaeus), the type BERG et al. 2014), is the largest in the order Trichoptera species) and northern Asia. It is absent from New Zea (recently surpassing Rhyacophila). Currently, about one land and the Chilean region of South America and most species in 20 within Trichoptera belongs in Chimarra, abundantly represented in tropical regions, especially the making the genus larger than most families of Tricho Neotropics (229 species) and southern Asia (321 species; ptera. Unlike Rhyacophila, which is primarily Holarctic MORSE 2014). A large number of additional species will in distribution (extending into tropical Asia), Chimarra likely be described, especially since some regions where ISSN 1863-7221 (print) | eISSN 1864-8312 (online) 345 Kjer et al.: Barcode data and Chimarra phylogenetics the genus occurs are incompletely inventoried (various This process began in the early 1800s when a flood of tropical localities, and especially Africa, Madagascar and new species were being described and the generic infra India). BLAHNIK (1998) estimated that an ultimate size of structure established by Linnaeus seemed inadequate for 1000 or more species was possible and probably repre accommodating them. For Trichoptera, this process be sents a conservative estimate. One of the goals of this gan much later than in many taxa, with the majority of paper is to assess a relatively simple strategy of molecu the diversity for the order only being described after the lar sequencing in order to add to the phylogenetic infra middle of the 20th century, although many genera were structure for this large genus. This strategy could then be established much earlier. One disadvantage to erecting applied to other Trichoptera genera. new genera from within a broadly defined older genus is that the establishment of new genera may leave the original genus paraphyletic. The disadvantages of para 1.1. On Chimarra and other large genera phyletic taxa were not properly appreciated until after the work of HENNIG (1950, 1966), and has led to the con We are also interested in how large genera come to be, vention of modern taxonomy, which requires monophyly and how they should be subdivided. It is acknowledged of taxa at all levels. A repercussion of this convention, that the size of a genus has a subjective component. In often criticized by non-taxonomists, is that it results in Trichoptera, genera tend to be conservatively defined, a considerable amount of nomenclatural instability due often based on distinctive larval differences (WIGGINS to frequent changes in genusspecies combinations. We 1981; SCHMID 1979). Many genera within Trichoptera have observed a recent preference in systematics toward probably have considerable antiquity (ROSS 1956; WAHL- establishing monophyletic genera, rather than arbitrar BERG & JOHANSON 2014) and it is understood that genera ily splitting genera that are acknowledged to be mono are not synchronized across orders. A large genus could phyletic into additional taxa, thus avoiding the problem potentially be the result of an old lineage, speciating at a of nomenclatural instability when it is unnecessary. We normal rate, for a long time, without dramatic morpho agree with this philosophy, and for this reason, the focus logical change, or alternatively, a relatively young line in this paper is in trying to establish a useful subgeneric age that has experienced a rapid burst of speciation. The infrastructure for the genus Chimarra, rather than split large number of species in Chimarra is mainly due to the ting the genus into additional genera. However, for Chi fact that it has not been divided into additional genera, marra, subgeneric taxa probably have more or less the demonstrating how generic definitions are dependent on same level of taxonomic significance as genera in other the uncoordinated decisions of systematists. The current taxa. size of the genus has resulted from recent descriptions of taxa (more than half the species described in just the last 50 years), and thus its size does not reflect some a priori 1.2. History of taxonomic effort in decision to establish a large genus. There is some value Chimarra in maintaining a broadly defined genus Chimarra. The genus has a number of distinctive apomorphies (BLAHNIK There are currently 3 genera in the philopotamid subfam 1998) and its monophyly is not in question. Moreover, ily Chimarrinae: Edidiehlia (a monotypic genus known members of Chimarra are easily recognized wherever only from the holotype), Chimarrhodella and Chimarra, they occur, both in the adult and larval stages, and can be the latter with 4 recognized subgenera, C. (Chimarra), readily identified as Chimarra in ecological studies and C. (Curgia), C. (Otarrha), and C. (Chimarrita). Curgia, biomonitoring programs. New species of Chimarra can Otarrha, and Chimarrita are confined to the New World. be unambiguously assigned to the genus during the de Like many genera, Chimarra has a history of taxo scription process. In contrast, natural subdivisions of the nomic shifts. The first attempt to consider relationships genus have not always been obvious. The major disad within Chimarra, on a world scale, was presented by vantage of accepting such a large, undivided genus is that ROSS (1956). The treatment was rather informal and the it tends to mask a great deal of evolutionary diversity. For major focus of his work was on species of Philopotami example, since Trichoptera are often used in biomonitor dae in the subfamily Philopotaminae. Most species of ing programs (in an effort to monitor water quality), and Chimarra were yet to be described. Nevertheless, his dis identifications of taxa are usually made only to the genus cussion of character evolution in the genus has continued level, the lumping of diverse lineages into a single genus to be of value. Ross recognized various lineages within diminishes the resolution of these efforts (DOHET 2002; Chimarra, but synonymized all previous genus-group RESH & UNZICKER 1975). Members of several distinctive taxa in Chimarrinae within the genus Chimarra, except lineages of Chimarra often cooccur in the same area and for several species considered to represent a distinct thus the broad definition of the genus and in our opinion, lineage, which he included in the genus