SUMMARY the Aim of the Present Study Was to Reveal Phylogenetic
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Phylogenetic Systematics and Historical Biogeography of Malesian Calicnemiine Damselflies (Odonata, Platycnemididae) Gassmann, Dirk Citation Gassmann, D. (2005, October 19). Phylogenetic Systematics and Historical Biogeography of Malesian Calicnemiine Damselflies (Odonata, Platycnemididae). Retrieved from https://hdl.handle.net/1887/9758 Version: Corrected Publisher’s Version Licence agreement concerning inclusion of doctoral thesis in the License: Institutional Repository of the University of Leiden Downloaded from: https://hdl.handle.net/1887/9758 Note: To cite this publication please use the final published version (if applicable). SUMMARY The aim of the present study was to reveal phylogenetic relationships within the damselfly subfamily Calicnemiinae (Odonata, Platycnemididae) as a basis for a historical-biogeographic scenario for the Malesian species. Beside that, taxonomic revisions at subgeneric and species-group level contribute to our knowledge of the diversity of the group. Chapter 1 and Chapter 2 together contain a taxonomic revision of the damselfly genus Idiocnemis Selys, 1878, from New Guinea and surrounding islands. Chapter 1 presents a revision of the presumably monophyletic Idiocnemis inornata species-group. Diagnoses of all nine previously described species are presented together with the description of two new species, viz. I. adelbertensis spec. nov. from northeastern New Guinea and I. australis spec. nov. from southern central New Guinea. Based on the morphology of the male ligula, three species-groups were distinguished provisionally: Group I from the Bird's Head Peninsula, Group II from the northern New Guinea ranges including the Bird's Head Peninsula region up to New Britain in the east, and Group III from (mainly) the southeastern Papuan archipelagos. The correct spelling of the subfamily name Calicnemiinae, based on Calicnemia Strand, 1928, is laid down in a nomenclatural note on the family-group name. In the Idiocnemis bidentata species-group, seven previously described species are redescribed, and one species, I. polhemi spec. nov., is described as new to science from southeastern New Guinea. The eight species, quite uniform in colour pattern and ligula morphology, are mainly differentiated by the inner structure of the male appendages. As for the I. inornata species-group, all species are keyed, and their distribution is mapped. Based on the Idiocnemis distribution patterns in New Guinea, the Vogelkop region (5 species), the western North New Guinea terranes (2 species) and the southeastern Papuan Peninsula (2 species) are recognized as larger areas of endemism; single endemics occur in the Adelbert Ranges, Huon Peninsula, New Britain, southwestern central New Guinea and southeastern central New Guinea. In Chapter 3, the subgenus Igneocnemis Hämäläinen, 1991, of the Philippine genus Risiocnemis Cowley, 1934, is revised. Descriptions and diagnoses of both sexes of all 15 previously recognized species are provided, and five new taxa are described, viz. R. antoniae spec. nov. and R. rubricercus spec. nov. from northeastern Mindanao, R. pistor spec. nov. from southeastern Mindanao, and R. kaiseri spec. nov. and R. nigra spec. nov. from Samar. The females of 11 species are described for the first time. Keys for males and females are provided. Characters of the male ligula and appendages and the female prothorax were studied by scanning electron microscopy. Based also on extensive new collections from across the Philippine archipelago, the distribution of all species is mapped. Four major areas of endemism are recognized from Igneocnemis distribution patterns: Luzon, the West Visayans, the East Visayans, and the Minadano region. But also northern and southern Luzon, eastern Mindanao, and the Dinagat/Panaon region are inhabited by endemic species. The Mindoro region is still insufficiently known. In Chapter 4 the phylogenetic relationships of Southeast Asian and Indo-Pacific Calicnemiinae are examined by cladistic analyses using morphological characters. A parsimony analysis, based on 88 characters and including 84 taxa, was performed resulting in 732 equally most parsimonious trees. Two species of the Platycnemidinae served as an outgroup. The strict consensus cladogram of the resulting equally most parsimonious trees supports the monophyly of the Papuan genus Idiocnemis Selys, 1878, the Philippine genus Risiocnemis Cowley, 1934, and its subgenera, but leaves the basal relationships of the African genera and the Palawan genus Asthenocnemis Lieftinck, 1949, partly unresolved. Based on assumptions on character evolution, a preferred phylogenetic hypothesis is presented showing a well supported 'Indo-Pacific clade' consisting of Philippine, New Guinean and Solomon island taxa, and as sister group Asthenocnemis. Risiocnemis turns out to be a sister group of Lieftinckia/Salomocnemis (Solomon Islands), the sister taxon of those being the central New Guinean Arrhenocnemis Lieftinck, 1933. Together, these form a monophyletic group with the remaining Papuan taxa. The possible effects of taxon sampling are discussed. Since all large genera appear to be monophyletic in the analysis, no major changes in classification are proposed. However, Idiocnemis leonorae Lieftinck, 1949, is transferred to Rhyacocnemis Lieftinck, 1956, comb. nov. based on four distinct synapomorphic traits. The monotypic Salomocnemis Lieftinck, 1987, clusters together with the remaining Solomon island taxa (the six species of Lieftinckia Kimmins, 1957), but synonymization of the two genera has been postponed due to instability in the cladograms. Chapter 5 places the Calicnemiinae in a context with other groups of freshwater organisms in Malesia. Present patterns in the distribution of the regional freshwater invertebrates are the result of complex historical and ecological processes. Many orders of aquatic insects are known in the fossil record from as early as the Early Permian, while the earliest fossils of Odonata date from the Middle Carboniferous. Thus, the breakup of Gondwana, that started in the Late Jurassic, is relevant to our understanding of the present distributional patterns. The geological history of Southeast Asia is extremely complex. The separation of India / Seychelles and Madagascar from Africa at 130 Ma, the subsequent breakup of India / Seychelles and Madagascar at 88 Ma, and the collision of India with Asia at 65–56 (or 43) Ma, significantly changed the western part of the area discussed. The southeastern part of the area changed under the influence of the northward rafting Australian plate from 85 Ma. The southwest directed subduction of the Pacific plate formed several arc-systems at the western margin of that plate. A very important reorganisation of plate boundaries occurred at 25 Ma, when the New Guinea passive margin collided with an island arc including the eastern Philippine, Halmahera and South Caroline arc-systems, and when the northwestern corner of the Australian plate collided with Southeast Asia in the Sulawesi region. Information on the subaerial history of the respective terranes is still fragmentary. Diversity and distribution of most groups of freshwater invertebrates of Southeast Asia are still underexplored, while phylogenetic reconstructions including taxa of South America or Africa are virtually absent. Various examples from the literature are discussed. A phylogenetic reconstruction and a historical-biogeographic scenario of the Platycnemididae, which special reference to the Calicnemiinae, is presented as one of the first examples of such an analysis of a widespread group. The Calicnemiinae of Southeast Asia are derived from African Platycnemididae. The sister-group of the Southeast Asian taxa is Leptocnemis cyanops Selys, a species confined to the Seychelles. The Malesian Calicnemiinae are derived from ancestors on the mainland of Asia, and may have dispersed along the Izu-Bonin arc at the subduction zone of the Pacific plate along the Philippine plate at 40-50 Ma, but alternatively, the Late Cretaceous 'Inner Melanesian Arc' (Mindanao to New Zealand) sensu Polhemus (1995) may have been the route of dispersal. A clade of the genera Lieftinckia and Risiocnemis, confined to the Solomon islands and the Philippines, respectively, represents a more recent westward dispersal of the Calicnemiinae, using the Caroline and Philippine Arcs during the Oligocene. Various other small-scale phylogenetic reconstructions and biogeographical analyses are discussed in Odonata and other freshwater invertebrates. Phylogenetic studies of aquatic and semiaquatic Heteroptera significantly contribute to our understanding of the areas of endemism and their relationships in Southeast Asia. The areas of endemism in New Guinea are generally congruent with geological entities recognized, e.g. the northern New Guinea terranes, as well as the central New Guinea terranes which are associated with an 'Inner Melanesian Arc'. Special attention is payed to the fauna of Sulawesi. Areas of endemism in Odonata and Heteroptera are generally congruent. Area cladistic reconstructions based on distribution patterns and phylogenetic reconstructions of e.g., Protosticta Selys (Odonata, Platystictidae) and genera and species of Chlorocyphidae (Odonata), show a pattern of (Northern arm(Southwest arm(Central + Southeast arm))), which is a reflection of the geological history of the island. The biogeographical patterns recognized in freshwater invertebrates of Malesia do not principally differ from those found in strictly terrestrial taxa.