The Phylogenetic System of Mantodea (Insecta: Dictyoptera)

The phylogenetic system of Mantodea (Insecta: Dictyoptera) Dissertation zur Erlangung des Doktorgrades der Mathematisch-Naturwissenschaftlichen Fakultäten der Georg-August-Universität zu Göttingen vorgelegt von Frank Wieland aus Oldenburg Göttingen 2010 D7 Referent: Prof. Dr. R. Willmann Korreferent: PD Dr. T. Hörnschemeyer Tag der mündlichen Prüfung: “In order to arrive at a rational classification for Mantodea, it would be helpful, first, to take an inventory of various useful morphological characteristics and evaluate their relative importance and, then, to determine for each which is primitive (plesiomorph) and which is derived (apomorph) by calculating which changes (probably) arose only once and which could have arisen several times. It is also necessary to consider the fact that major variations do not necessarily mean a distant phylogenetic relationship and that striking resemblances do not necessarily translate into a close relationship.” Roger Roy, 1999 “Da es in dieser Gruppe äußerst schwierig ist, Primitives, Einfaches von Vereinfachtem zu unterscheiden, und da sicher eine Menge von Konvergenzen vorliegen, bedarf es noch weiterer sorgfältiger morphologischer Untersuchungen.” Anton Handlirsch, 1930a “[Morphology] is the most interesting department of natural history, and may be said to be its very soul.” Charles Darwin, 1859 Abstract The first reconstruction of mantodean phylogeny using a large morphological dataset of the entire group is presented. 152 morphological characters were encoded for 122 species of Mantodea, encompassing all 15 currently recognized families, 34 of 48 subfamilies (71 %) and 33 of 46 tribus (72 %). Structures from the entire exoskeleton were studied, including characters that have been stated to be convergent de- velopments before without data-based evidence. Fossils, behaviour and ontogenetic observations were used for the interpretation of structures and the discussion of evolutionary scenarios. Calculations resulted in 888 equally parsimonious trees (analysis I). Many characters were found to be highly homoplastic, resulting in consensus cladograms with low resolution except for many smaller distal clades. Characters were automatically reweighted (based on the Rescaled Consistency Index). Subsequent calculation (analysis II) resulted in 10 equally parsimonious trees, and the consensus clado- gram was almost fully resolved. Most of the small monophyletic groups found in analysis I were recov- ered in analysis II. The resulting phylogenetic reconstruction supported the monophyly of five traditional families (Acanthopidae, Empusidae, Eremiaphilidae, Thespidae, and Toxoderidae; 33 %), of 11 subfamilies (Amorphoscelinae, Angelinae, Chroicopterinae, Empusinae, Haaniinae, Hymenopodinae, Oxypilinae, Paraoxypilinae, Perlamantinae, Toxoderinae, and Tropidomantinae; 32 % of the subfamilies studied) and of six tribus (Angelini, Chroicopterini, Idolomorphini, Oxypilini, Polyspilotini, and Rivetinini; 18 % of the tribus studied). The subgroups of Amorphoscelidae in the traditional sense clustered together in analysis II (not in analysis I), however the group encompassed Compsothespis (which is usually as- sumed to belong to Mantidae) as the sistergroup of Amorphoscelinae + Perlamantinae within Amorpho- scelidae. The potential likeliness of this scenario was discussed in detail. Many structures have been shown to have evolved many times independently in Mantodea, most likely due to comparable selective pressures in the respective habitats. Among them are the head processes, lamellar expansions of the pronota, and lobes on the legs and on the abdomen. Furthermore, the metathoracic hearing organ (“cyclopean ear”) evolved several times independently and possibly separately in males and females in some cases. Molecular studies have instead found evidence for a monophyletic neotropical earless taxon in the basal part of the phylogenetic tree. Thespidae was found to be monophyletic and to include Oligonicinae as well as Haaniinae, nested among the latter. The monophyly of Oligonicinae including Haaniinae is supported by their unique fore tibial morphology. This phylogenetic relationship implicates that the ear in Haaniinae originated independently form other taxa, as the group is nested among the earless Oligonicinae. Congruence between the morphological reconstruction of the phylogeny and the traditional classification was higher than that between the latter and the results of molecular analyses. This was probably at least partly caused by the choice of characters that are often also used in taxonomy, which in turn was always meant to reflect phylogeny, at least to a certain degree. Another possibility is that the taxon sample was smaller in the present analysis than in recent molecular studies. Congruence with molecular data was comparatively low. Relationships that are also supported (with reservations) by morphological data are the basal dichotomy between Chaeteessa and the remaining Mantodea and the monophyly of Artimantodea (with reservations regarding the position of Metallyti- cus). Furthermore, Paraoxypilinae, Amorphoscelinae, Ciulfina + Stenomantis, Hestiasula + Oxypilinae, Oxypilinae, Pyrgomantis + (Tarachodes + Tarachodula), Chroicopterinae (except for Chroicoptera), Rivetinini, Leptocola + Stenopyga, Empusidae, Empusinae, Polyspilotini, Oxyothespis + Toxoderidae, Toxoderidae, part of Hymenopodinae including Hymenopus + Theopropus, Photina + (Orthoderella + Acanthopidae), and Acanthopidae were found to be monophyletic in both molecular and the present studies. Study of first instar nymphs yielded new interpretation of structures found in the adults of several species. Chaeteessa, Metallyticus and Mantoida were available for SEM studies for the first time. First observations of living Mantoida and Metallyticus and first pictures of living and freshly deceasedChaeteessa specimens in combination with the scarce literature data allowed hypotheses regarding their lifestyles and interpretations of the corresponding morphological adaptations. The tibial spur in Chaeteessa is still present, albeit strongly reduced. Discoidal spines are still present in first instar nymphs of Metallyticus and a single discoidal spine persists in the adults. Observations of living specimens in combination with literature data led to the tentative hypothesis that a bark-dwelling lifestyle may represent the plesiomor- phic condition for Mantodea. The hypothesis of distinct mantodean ecomorphs suggested by Svenson & Whiting (2009) was cor- roborated. As in the molecular studies, the Australasian and the South-East Asian species of the tree- dwelling Liturgusidae were found to be unrelated. Details in the morphology of the head processes suggest that the Indian Didymocorypha and the African Pyrgomantis, both superficially nearly identical grass dwellers, gained their distinctive body shape independently when they adapted to a life in the grasslands. Female morphological digging adaptations for laying the ootheca into the soil were compared. At least four distinct types of digging devices evolved independently: The Eremiaphilidae-type (spines on sternite 6, sternite 6 partly covering sternite 7), the Ligaria-type (distal bipartite hooks on the gonapo- physes VIII), the Chroicoptera-type (spines on the distal part of sternite 7) and the Rivetina-type (spines on the proximal part of sternite 7). There are possibly two more types that have not been studied in the present dataset. The morphology of many structures was discussed with regard to the fossil record. Besides the discussion of several fossils that were described previously, a fossil first instar nymph from Baltic amber was reconstructed threedimensionally from μ-CT data. Comparison of fossils and first instar nymphs and adults of several extant species made it possible to discuss so-believed unusual characters in fossils. For example, a strongly elongated distal postero-ventral fore tibial spine that was described to be special for some fossils is present in the first instar nymphs of many extant species and also in the adults of some species. Four cercomeres are present in the first instar nymphs of extant Mantodea. This character may help to assign the ontogenetic age of mantodean nymphs in amber. Observations on the evolution of head processes, male antennomeres, pronotal lobes, foreleg morphology of Chaeteessa and Metallyticus, tarsal morphology of Heteronutarsus, postembryonic devel- opment, sexual dimorphism, female digging devices, trends in leg morphology, sound production, and on the metathoracic hearing organ were summarized and discussed in detail. A discussion of the early mantodean lifestyle and an outlook to future research topics were provided. Table of contents 1 Introduction 5 2 State of knowledge 7 2.1 Systematics 7 2.1.1 Phylogenetic relationships of Dictyoptera 7 2.1.2 Systematic position of Dictyoptera within Polyneoptera 9 2.1.3 Monophyly of Mantodea 10 2.1.4 Relationships within Mantodea and review of the main taxa of the current classification 11 2.1.5 Further systematic hypotheses 40 2.2 Palaeontological record 43 2.3 Biogeography 47 3 Material and methods 50 3.1 Techniques 50 3.2 Phylogenetic methods 50 3.3 Morphological terminology, definition of orientations and measuring, character encoding 51 3.4 Material 55 4 Results and discussion 56 4.1 Characters 56 4.1.1 Head and appendages 56 4.1.2 Thorax and appendages 70 4.1.3 Abdomen and appendages 168 4.2 Calculations 183 4.2.1 Analysis I 183 4.2.2 Analysis II 184 4.2.3 Bootstrap

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