TAXONOMY, PHYLOGENY AND BIOGEOGRAPHY OF THE PRIONOCERIDAE (INSECTA: COLEOPTERA: CLEROIDEA) IN THE INDOCHINESE SUBREGION. Inauguraldissertation zur Erlangung der Würde eines Doktors der Philosophie vorgelegt der Philosophisch-Naturwissenschaftlichen Fakultät der Universität Basel von Michael Felix Geiser aus Roggliswil, Luzern (CH) Basel, 2015 Originaldokument gespeichert auf dem Dokumentenserver der Universität Basel edoc.unibas.ch 2 Genehmigt von der Philosophisch-Naturwissenschaftlichen Fakultät auf Antrag von Prof. Dr. Peter Nagel und Prof. Dr. Thomas Wagner Basel, den 25. März 2014 Prof. Dr. Jörg Schibler Dekan 3 Contents Chapter I: Introduction .................................................................................................. 5 Chapter II: The status quo: A World taxonomic catalogue of Prionoceridae (Coleoptera: Cleroidea). .............................................................................................. 11 Chapter III: A revision of the genus Idgia Castelnau, 1838 in Laos, Vietnam and Cambodia, with description of a new genus, Bigdia n. gen. ....................................... 37 Chapter IV: Description and revision of a new genus, Palpolobonyx. ..................... 147 Chapter V: An updated key to genera of Prionoceridae. ........................................... 203 Chapter VI: A first broad-scale molecular phylogeny of Prionoceridae (Insecta: Coleoptera: Cleroidea): using molecular data to understand taxonomy, morphological change, life history and biogeography. ...................................................................... 205 Chapter VII: Conclusions. ......................................................................................... 225 Acknowledgements. .................................................................................................. 229 References. ................................................................................................................ 231 Nomenclatural disclaimer: All nomenclatural acts, including new genus and species group names proposed in this dissertation are not available according to ICZN, art. 11 (ICZN, 1999). This dissertation does not constitute a published work for the purposes of zoological nomenclature, as defined in ICZN Art. 8. All nomenclatural acts will only be available after chapters III and IV have been published separately, in an appropriate journal or monograph. 4 Bigdia maculatithorax (Pic, 1919) – Laos, Xieng Khouang, Mt. Phou Sane. 5 Chapter I Introduction Indochina is one of the most biodiverse areas on Earth, and has been proposed as one of the World's 25 "biodiversity hotspots" (Myers & al., 2000). The term "hotspot", applied by Myers & al., does not only imply an exceptionally high number of species and higher taxa concentrated in an area, but also points out the biodiversity within that area is threatened by extinction. In the case of Indochina, the ongoing human exploitation of natural resources, fuelled by population growth and economic development, has already lead to extensive deforestation and other large-scale habitat destruction, leading to the extinction of several mammal and bird species (Duckworth & al., 1999). To resolve the ongoing crisis of habitat destruction and biodiversity loss in Indochina, general knowledge about the area's species richness is urgently needed. Any attempts to overcome this knowledge crisis can only be successful if the species within this area are known, along with their habitat requirements, distributions and phylogenetic relationships. This currently stands in stark contrast to the current situation, where Indochina's biodiversity is poorly known. Even in well-known organisms, such as mammals, an astonishing number of previously unknown species has been described from eastern Indochina since the 1990ies (Conservation International, 2011). The state of knowledge in Indochina is especially poor for beetles (Coleoptera), which make up about 25% of the total species diversity worldwide (Hunt & al., 2007). Taxonomic treatments and identification keys for Indochinese beetles are scarce, and often completely outdated. Only few Coleoptera families have been thoroughly revised for major parts of Indochina, such as Chrysomelidae (Kimoto & Gressitt, 1979; 1981; 1982; Kimoto, 1989; 1998; 1999; 2000), Cerambycidae (Gressitt & al., 1970) and Scarabaeidae (Paulian, 1945). While these three families are still among the more popular and well-known Coleoptera groups, the families formerly included in the so-called "Malacodermata" are among the most neglected. "Malacodermata" is a traditional family-group name widely used during the 19th and early 20th century (e. g. Laporte de Castelnau, 1840; Lacordaire, 1857; Wittmer, 1941). It included beetles with all 5-segmented tarsi, soft cuticula and relatively flexible body, which have likewise been treated as members of a single family Cantharidae, in the past (e.g. Reitter, 1911). Since the inclusion of larval morphological data into beetle phylogeny (Böving & Craighead, 1931), this family concept has become obscure, and members of "Malacodermata" are now included in two different superfamilies, Elateroidea and Cleroidea (Lawrence & Newton, 1995; Bocakova & al., 2007; Bouchard & al., 2011; Bocakova & al., 2012). Nevertheless, the old concept of "Malacodermata" has not entirely died out. The general appearance of "malacoderm" families, such as Cantharidae, Melyridae, Prionoceridae can be extremely similar, probably in as an adaptation to similar life-histories (Crowson, 1955; 1981). The soft-bodiedness of these families have posed a real challenge to morphological taxonomy, due to the reduction of several external structures, which are otherwise used as sources for phylogenetic data (Crowson, 1981). This has lead to the same character complexes being used in taxonomy of both Cantharidae and Melyridae (s. lat.) and to a large number of contemporary taxonomists specialising in both "cantharoids" and Cleroidea. Prionoceridae is a relatively small group of typical "malacoderm" beetles, belonging to the melyrid lineage within the superfamily Cleroidea (the so called "soft-winged flower beetles). They have been treated as a subfamily of Melyridae in a wider sense, e.g. by Crowson, 1964 and Majer, 1987, but are now more often regarded as a separate family (Lawrence & Newton, 1995; Lawrence & Leschen, 20910; Bouchard & al., 2011). The most recent family-level phylogeny of the clade containing Prionoceridae was published by Bocakova & al. (2012). Their classification of the "melyrid lineage" included the families Rhadalidae, Mauroniscidae, 6 Prionoceridae, Melyridae, Dasytidae and Malachiidae, which are all included in Crowson's (1964) concept of "Melyridae" (in a wider sense). Bocakova & al.'s analysis placed Prionoceridae as one of the basal families of the melyrid lineage, but not as the most basal one. This implies that, should someone continue to use Crowson's wider concept of Melyridae, they would fall within this clade and should rather be treated as a subfamily. This contradicts Bouchard's (2011) classification, which also uses a wider concept of Melyridae, but excludes Prionoceridae from it. The number of species currently placed in Prionoceridae stands at 158 (see Chapter II) and their distribution is limited to the Old World tropics and subtropics, including the southern parts of the Palearctic, the whole Oriental (Indo-Malayan) region, most of the Afrotropics, as well as minor parts of the Australian region (New Guinea and Micronesia). The Oriental region is, by far, the most species-rich in terms of prionocerids (Champion, 1919; Pic, 1926). At the current state of knowledge (see Chapter II), two parts of the Oriental region appear to be exceptionally rich in species: The area including South India and Sri Lanka (termed "Ceylonese subregion" by Wallace, 1876) and the area including the Malay Peninsula and the Greater Sunda islands, termed "Sundaland" by Wallace, 1876. This distribution of species diversity may be highly biased by collecting efforts and taxonomic treatments. As stated before, the Indochinese subregion is particularly poorly-known. Most Prionoceridae are superficially very similar to members of two other beetle families, Cantharidae and Oedemeridae. This has lead to many mis-classifications and still poses a problem when looking for them in institutional collections. The majority of museum collections visited during the course of this work had prionocerid specimens sorted under the wrong families, including even some of the most well-curated collections. The similarity of prionocerids with Cantharidae has also lead to their placement within the same family-group taxon "Malacodermata" (as discussed above) for over a century. The evolutionary reasons for this similarity have never been thoroughly examined, but it can be assumed that similar life-history strategies are at least partially responsible (Crowson, 1981; Crowson, 1995). Both Cantharidae and Prionoceridae have predatory larvae and short-lived adults, which are usually flower visitors. The reduction of cuticular features and sclerotisation (soft-bodiedness) may have evolved in response to the short life-span of the adults, which could have made the evolution of strong body armour unnecessary and a waste of resources. Chemical defense probably also plays a major role. While chemical defense mechanisms are well-known in Cantharidae (Poinar & al., 2007), their existence has not yet been published for Prionoceridae, but is known for some of their close