Technische Universität München Lehrstuhl für Zoologie Integrative taxonomy and evolution of the hyperdiverse weevil genus Trigonopterus René Tänzler Vollständiger Abdruck der von der Fakultät Wissenschaftszentrum Weihenstephan der Technischen Universität München zur Erlangung des akademischen Grades eines Doktors der Naturwissenschaften genehmigten Dissertation. Vorsitzender: Prof. Dr. H. Luksch Prüfer der Dissertation: 1. apl. Prof. Dr. R. Gerstmeier 2. Prof. Dr. J. Geist Die Dissertation wurde bei der Technischen Universität München am 01.03.2016 eingereicht und durch die Fakultät Wissenschaftszentrum Weihenstephan am 18.04.2016 angenommen. 1 2 Contents I Eidesstattliche Erklärung …………………………………………………..... 4 II Summary …………………….…………………………………………………. 5 III Zusammenfassung ...……….…………………………………………………. 5 IV List of publications …………………………………………………..…….…… 9 V Contributions ………………………………………………………..………… 10 1 Introduction ……………………………………………………………….…… 11 1.1 The genus Trigonopterus ……………………………………..…... 11 1.2 The Southeast Asian region ………………………………............ 11 1.3 Sampling ……………………………………………………….....… 13 1.4 Morphological work ………………………………………………… 14 1.5 Molecular work and sequence data analysis ………………….… 15 1.6 Species delineation – tools for determining and describing new species ………………………………………………….……… 15 1.7 Phylogenetics and ancestral area reconstruction …………..…… 16 2 Aims ……………………………………………………………………...……..... 19 3 Publication I …………………………………………………………….…….... 20 4 Publication II ………………………………………………………………….... 31 5 Publication III ……………………………………………………….………..... 181 6 Publication IV ……………………………………………………….………..... 190 7 Synthesis ……………………………………………………………………….. 198 7.1 Tackling the hyperdiverse and mostly undescribed fauna of New Guinea ……………………………………….……………………..... 198 7.2 Turbo taxonomy …………………………………………….………. 200 7.3 Multiple transgression of Wallace´s Line – an unexpected distribution pattern in Trigonopterus …………......………………. 204 7.4 Conclusion ………………………………………………………..…. 206 8 Outlook …………………………………………………………………….……. 208 9 References …………………………………………………………………….... 209 10 Acknowledgements ……………………………………………..…………….. 215 11 Appendix ……………………………………………………………..…………. 216 3 I Eidesstattliche Erklärung Hiermit erkläre ich an Eides statt, dass ich die der Fakultät Wissenschaftszentrum Weihenstephan für Ernährung, Landnutzung und Umwelt der Technischen Universität München zur Promotionsprüfung vorgelegte Arbeit mit dem Titel “Integrative taxonomy and evolution of the hyperdiverse weevil genus Trigonopterus” an der Zoologischen Staatssammlung München (ZSM) und in Kooperation mit dem Staatlichen Museum für Naturkunde Karlsruhe (SMNK) unter der Anleitung und Betreuung von Dr. Michael Balke (ZSM) und Dr. Alexander Riedel (SMNK) ohne sonstige Hilfe erstellt und bei der Abfassung nur die gemäß § 6 Abs. 6 und 7 Satz 2 Promotionsordnung der TU München angegebenen Hilfsmittel benutzt habe. Ich habe keine Organisation eingeschaltet, die gegen Entgelt Betreuerinnen und Betreuer für die Anfertigung von Dissertationen sucht, oder die mir obliegenden Pflichten hinsichtlich der Prüfungsleistungen für mich ganz oder teilweise erledigt. Weiterhin erkläre ich, dass ich an keiner anderen Stelle ein Prüfungsverfahren beantragt bzw. die Dissertation in dieser oder anderer Form bereits anderweitig als Prüfungsarbeit verwendet oder einer anderen Fakultät als Dissertation vorgelegt habe. Ich habe den angestrebten Doktorgrad noch nicht erworben und bin nicht in einem früheren Promotionsverfahren für den angestrebten Doktorgrad endgültig gescheitert. Die öffentlich zugängliche Promotionsordnung der Technischen Universität München ist mir bekannt, insbesondere habe ich die Bedeutung von § 28 (Nichtigkeit der Promotion) und § 29 (Entzug des Doktorgrades) zur Kenntnis genommen. Ich bin mir der Konsequenzen einer falschen Eidesstattlichen Erklärung bewusst. Mit der Aufnahme meiner personenbezogenen Daten in die Alumni-Datei bei der TUM bin ich einverstanden. München, den 4 II Summary Weevils are one of the most successful groups of organisms, comprising more than 62,000 described species (Oberprieler 2007) with numbers of discovered species rising rapidly. Since the first weevil descriptions by Carolus Linnaeus (1758) 250 years ago, the number of described species has increased by a 1000-fold. Cryptorhynchinae are one of the major subfamilies within the Curculionoidea to which Trigonopterus belongs to. Trigonopterus is a genus of flightless and usually small weevils. Nevertheless, this genus exhibits a broad distribution ranging from Taiwan to New Caledonia and from Sumatra to Samoa. Its center of diversity is in New Guinea. At the start of this project, 90 species of Trigonopterus were described (Riedel 2010). Species delineation using DNA based methods was demonstrated to be an effective tool based on the 48 new species described from the Cyclops Mountains of New Guinea (Riedel et al. 2010). In my first publication 1,002 specimens were selected out of 6,500 specimens collected and examined with molecular and morphological methods. The latter method yielded 270 morphospecies. Cox1 sequences were used for delimitating species with two different methods; “Objective Clustering” and the “Generalized Mixed Yule Coalescent” (GMYC) method. Out of the 279 morphospecies both methods perfectly assigned 258, and 239 species respectively. Taxonomic accuracy (the proportion of DNA groups that agree with morphology-based species hypotheses) for both methods was 93.1%, and 86.4%respectively. Additionally both methods outperformed the parataxonomist (31.6% taxonomic accuracy). Furthermore, nine cryptic species were found for which additional nuclear markers showed congruent results with the mitochondrial data. This demonstrates that integrative taxonomy facilitates a fast and reliable species identification method even for largely unexplored and hyperdiverse groups. Trigonopterus weevils are an important part of biodiversity, both in number of species and in terms of being a sensitive bioindicator of forest health. An inventory of species makes it possible to find hotspots of biodiversity that can be prioritized for conservation. Describing the vast number of species found in tropical regions with traditional taxonomic methods would not be efficient enough, given the pace at which their habitats are being destroyed. As a result of the rapid destruction of living environments it is necessary to develop new techniques that allow for faster but still sound identification of species. Publication II and III demonstrate how to determine and to describe a large number of species. The results confirm that mitochondrial cox1 data is ideal for identification of Trigonopterus species. Out of the 279 species (Tänzler et al. 2012) 101 were selected and described. Owing to the high number of species, descriptions were kept to a minimum and illustrations restricted to the dorsal aspect of habitus and male genital. Additionally DNA- 5 barcodes were used to replace an identification key which would be difficult to use in such a large genus with many undescribed species. DNA Barcoding is a tool that will help delimit species in many hyperdiverse groups and will pave the road to additional comparative studies, e.g. in community ecology, phylogeography and large scale biogeographic studies. In publication IV, eight species of Trigonopterus occurring on Bali have been investigated. Bali is located west of Wallace´s Line which separates Orientalis and Australis. Bali and islands west of it have been connected to mainland Asia repeatedly, as a result of the lower sea levels during the Pleistocene. This facilitated an exchange of species. In contrast, the deep ocean trench that separates Bali from the Australis towards the east has not seen a great interchange of Australian fauna. These circumstances should have resulted in a stronger influence of the Javanese fauna in Bali and a lesser influence of the fauna of the Australis (Braby et al. 2007, Hendrich & Balke 1995, MacKinnon 1993, McKay 2006). However, most of the previous studies focused on vertebrates and were not based on robust phylogenetic data (Rensch 1936). By using molecular phylogenetics and ancestral area reconstruction it was demonstrated that Trigonopterus dispersed from the east and passed Wallace´s Line repeatedly. On Bali a radiation with eight species of Trigonopterus took place. The crossing of Wallace´s Line is even more surprising considering the small body size and winglessness of this genus, resulting in many narrowly endemic species. This highlights the importance of detailed and comprehensive surveys in this highly complex biogeographic region. Future research on Trigonopterus will need to focus on reconstructing and dating their geographical expansion as well as pinpointing the group´s center of origin. Another aim is to establish Trigonopterus as an indicator organism in terms of biodiversity conservation. These investigations will bring further valuable insights into evolutionary processes and patterns of biodiversity. 6 III Zusammenfassung Rüsselkäfer und deren nächste Verwandte (Curculionoidea) stellen mit über 62000 bekannten Arten eine der erfolgreichsten Gruppen im Tierreich dar (Oberprieler 2007). Seit der ersten Beschreibung von Carolus Linnaeus (1758) vor über 250 Jahren hat sich deren Anzahl um den Faktor 1000 erhöht. Mit ca. 6000 Arten sind die Cryptorhynchinae, zu denen auch die Gattung Trigonopterus gehört, eine der größten Unterfamilien. Trigonopterus ist eine Gattung kleiner, flugunfähiger Käfer, welche dennoch eine