Comparative Morphology of the Orthopteran Thorax With a Discussion of Phylogenetically Relevant Characters

Fanny Leubner, Benjamin Wipfler, Sven Bradler (2017): Comparative Morphology of the Orthopteran Thorax With a Discussion of Phylogenetically Relevant Characters. Insect Systematics and Diversity 1 (1): 29-47, DOI: 10.1093/isd/ixx00

The thorax of the cave cricket Troglophilus neglectus: anatomical adaptations in an ancient wingless insect lineage (Orthoptera: Rhaphidophoridae)

Thoracic muscles of different representatives of Polyneoptera homologized following nomenclature by [ 36 ]. (XLSX 21 kb

When Giant Stick Insects Play With Colors: Molecular Phylogeny of the Achriopterini and Description of Two New Splendid Species (Phasmatodea: Achrioptera) From Madagascar

Achrioptera is a taxon of extremely large and exceptionally colorful stick insects endemic to Madagascar and the Comoros Archipelago. We studied the phylogenetic position of the Achriopterini, comprising the genera Achrioptera and Glawiana, based on a multigene phylogeny and concluded that it is a sister group to other Madagascan phasmids (Anisacanthidae) rather than to Neotropical or Australo-Pacific groups as was suggested in a previous study based on morphology. Our results also point to unresolved relationships (potential paraphyly of Achrioptera), taxonomic issues (elevation of A. punctipes cliquennoisi to species level), and detection of cryptic diversity (in A. impennis), demonstrating the need of additional research. A DNA barcoding approach based on COI sequences of Achrioptera species revealed a clear discrimination between closely related and morphologically similar species. Applying integrative taxonomy using multiple lines of evidence, we demonstrated that the well-known species with blue males from Montagne des Français and Foret d'Orangea in the far north of Madagascar, previously attributed to Achrioptera fallax, represents a new species, which we describe as Achrioptera manga sp. nov. based on morphological, chromatic, and genetic (mitochondrial and nuclear) differences. We also describe a second new giant species from this massif: Achrioptera maroloko sp. nov. is among the largest insects (females reaching up to 24 cm total length) and differs from its sister species A. spinosissima from western Madagascar in morphology, coloration, and substantial DNA barcode divergence. These magnificent new species confirm the significance of the Montagne des Français area as a hotspot of biodiversity and microendemism. The biogeographic pattern of the species pair A. fallax/A. manga is paralleled by species pairs of reptiles and amphibians suggesting a similar evolutionary history. Finally, we discuss the sexual dichromatism of Achrioptera species with conspicuous males and mostly cryptic females. As possible reasons, we consider female mate choice and divergent habits of males and females, but aposematism combined with toxic substances produced in defense glands or accumulated in the insect's body from nutritional plants are more plausible explanations for this phenomenon

Evolution of Oviposition Techniques in Stick and Leaf Insects (Phasmatodea)

Stick and leaf insects (Phasmatodea) are large, tropical, predominantly nocturnal herbivores, which exhibit extreme masquerade crypsis, whereby they morphologically and behaviorally resemble twigs, bark, lichen, moss, and leaves. Females employ a wide range of egg-laying techniques, largely corresponding to their ecological niche, including dropping or flicking eggs to the forest floor, gluing eggs to plant substrate, skewering eggs through leaves, ovipositing directly into the soil, or even producing a complex ootheca. Phasmids are the only insects with highly species-specific egg morphology across the entire order, with specific egg forms that correspond to oviposition technique. We investigate the temporal, biogeographic, and phylogenetic pattern of evolution of egg-laying strategies in Phasmatodea. Our results unequivocally demonstrate that the ancestral oviposition strategy for female stick and leaf insects is to remain in the foliage and drop or flick eggs to the ground, a strategy that maintains their masquerade. Other major key innovations in the evolution of Phasmatodea include the (1) hardening of the egg capsule in Euphasmatodea; (2) the repeated evolution of capitulate eggs (which induce ant-mediated dispersal, or myrmecochory); (3) adapting to a ground or bark dwelling microhabitat with a corresponding shift in adult and egg phenotype and egg deposition directly into the soil; and (4) adhesion of eggs in a clade of Necrosciinae that led to subsequent diversification in oviposition modes and egg types. We infer at minimum 16 independent origins of a burying/inserting eggs into soil/crevices oviposition strategy, 7 origins of gluing eggs to substrate, and a single origin each of skewering eggs through leaves and producing an ootheca. We additionally discuss the systematic implications of our phylogenetic results. Aschiphasmatinae is strongly supported as the earliest diverging extant lineage of Euphasmatodea. Phylliinae and Diapheromerinae are both relatively early diverging euphasmatodean taxa. We formally transfer Otocrania from Cladomorphinae to Diapheromerinae and recognize only two tribes within Diapheromerinae: Diapheromerini sensu nov. and Oreophoetini sensu nov. We formally recognize the clade comprising Necrosciinae and Lonchodinae as Lonchodidae stat. rev. sensu nov

Die Phylogenie der Stab- und Gespenstschrecken (Insecta: Phasmatodea)

Softcover, DIN A4Stab- und Gespenstschrecken sind nachtaktive große Insekten aus vorwiegend tropischen Gebieten. Sie gelten innerhalb der Insekten als eine eigenständige „Ordnung“, Phasmatodea, und sind bekannt für ihre Eigenschaft, in erstaunlicher Weise Zweige und Blätter nachzuahmen, um sich vor ihren Feinden zu tarnen. In den vergangenen Jahrzehnten, in denen die Erforschung der Insektenevolution rasante Fortschritte gemacht hat, haben die Phasmatodea kaum Beachtung gefunden. Der vorliegende Band bietet eine umfangreiche Analyse der verwandtschaftlichen Beziehungen und Evolution der Phasmatodea, basierend auf einer gründlichen Untersuchung zahlreicher anatomischer und verhaltensbiologischer Merkmale, und gelangt zu neuen Hypothesen, die vielen traditionellen Ansichten zur Stammesgeschichte dieser Insektengruppe widersprechen. Die neuen Ergebnisse werden unter eingehender Berücksichtigung und Auswertung der bestehenden Literatur und neuster Befunde aus der Molekularbiologie ausgiebig diskutiert. Hierbei lassen sich längst nicht alle Fragen befriedigend klären, und der Bedarf an zukünftiger Forschung wird an allen entscheidenden Punkten kenntnisreich aufgezeigt. Einen Schwerpunkt der Arbeit bildet die Diskussion der Flügel-Evolution bei den Stabschrecken. Nach molekularbiologischen Befunden sollen die Flügel entgegen früherer Annahmen bei dem Vorfahren aller Phasmatodea verloren gegangen sein und bei einigen jüngeren evolutiven Linien eine Rückkehr erfahren haben, also re-evolviert worden sein. Um das Phänomen der Re-Evolution wird seither leidenschaftlich gestritten, und es erfährt eine entsprechend ausgiebige Erörterung in der vorliegenden Monographie.Stab- und Gespenstschrecken sind nachtaktive große Insekten aus vorwiegend tropischen Gebieten. Sie gelten innerhalb der Insekten als eine eigenständige „Ordnung“, Phasmatodea, und sind bekannt für ihre Eigenschaft, in erstaunlicher Weise Zweige und Blätter nachzuahmen, um sich vor ihren Feinden zu tarnen. In den vergangenen Jahrzehnten, in denen die Erforschung der Insektenevolution rasante Fortschritte gemacht hat, haben die Phasmatodea kaum Beachtung gefunden. Der vorliegende Band bietet eine umfangreiche Analyse der verwandtschaftlichen Beziehungen und Evolution der Phasmatodea, basierend auf einer gründlichen Untersuchung zahlreicher anatomischer und verhaltensbiologischer Merkmale, und gelangt zu neuen Hypothesen, die vielen traditionellen Ansichten zur Stammesgeschichte dieser Insektengruppe widersprechen. Die neuen Ergebnisse werden unter eingehender Berücksichtigung und Auswertung der bestehenden Literatur und neuster Befunde aus der Molekularbiologie ausgiebig diskutiert. Hierbei lassen sich längst nicht alle Fragen befriedigend klären, und der Bedarf an zukünftiger Forschung wird an allen entscheidenden Punkten kenntnisreich aufgezeigt. Einen Schwerpunkt der Arbeit bildet die Diskussion der Flügel-Evolution bei den Stabschrecken. Nach molekularbiologischen Befunden sollen die Flügel entgegen früherer Annahmen bei dem Vorfahren aller Phasmatodea verloren gegangen sein und bei einigen jüngeren evolutiven Linien eine Rückkehr erfahren haben, also re-evolviert worden sein. Um das Phänomen der Re-Evolution wird seither leidenschaftlich gestritten, und es erfährt eine entsprechend ausgiebige Erörterung in der vorliegenden Monographie

Fig. 8 in Comparative Morphology of the Orthopteran Thorax With a Discussion of Phylogenetically Relevant Characters

Fig. 8. Thoracic muscles of Meconema meridionale. Right body half. Interior lateral view. (A) Pleuropleural, tergopleural, sternopleural, and ventral longitudinal muscles. (B) Slightly shifted dorsolateral view of the pterothorax. Pterothoracic tergopleural muscles. Blue asterisks mark pleural ridge. abt 1 (first abdominal tergite), em 2 / 3 (meso- / metathoracic epimeron), est 2 / 3 (meso- / metathoracic episternum), nt 2 / nt 3 (meo- / metanotum). Scale bars: 1 mm

Notes on the leaf insects of the genus Phyllium of Sumatra and Java, Indonesia, including the description of two new species with purple coxae (Phasmatodea, Phylliidae)

Within the last two years, the leaf insects of the genus Phyllium of both the islands of Java and Sumatra have been reviewed extensively based on morphological observations. However, cryptic species which cannot be differentiated morphologically may be present among the various populations. Since it has frequently been demonstrated that analyses based on molecular data can bring clarity in such cases, we conducted a phylogenetic analysis based on three genes (nuclear gene 28S and mitochondrial genes COI and 16S) from the Phyllium species of these islands. The results show distinct molecular divergence for several populations and suggest the presence of two new cryptic species, morphologically inseparable from Phyllium hausleithneri Brock, 1999. From Sumatra, the population originally thought to be a range expansion for Phyllium hausleithneri, is now here described as Phyllium nisus sp. nov., with the only consistent morphological difference being the color of the eggs between the two populations (dark brown in P. hausleithneri and tan in P. nisus sp. nov.). Further, an additional population with purple coxae from Java was morphologically examined and found to have no consistent features to separate it morphologically from the other purple coxae species. This cryptic species from Java was however shown to be molecularly distinct from the other purple coxae populations from Sumatra and Peninsular Malaysia and is here described as Phyllium gardabagusi sp. nov. In addition, Phyllium giganteum is here officially reported from Java for the first time based on both historic and modern records of male specimens

Notes on the leaf insects of the genus Phyllium of Sumatra and Java, Indonesia, including the description of two new species with purple coxae (Phasmatodea, Phylliidae)

Within the last two years, the leaf insects of the genus Phyllium of both the islands of Java and Sumatra have been reviewed extensively based on morphological observations. However, cryptic species which cannot be differentiated morphologically may be present among the various populations. Since it has frequently been demonstrated that analyses based on molecular data can bring clarity in such cases, we conducted a phylogenetic analysis based on three genes (nuclear gene 28S and mitochondrial genes COI and 16S) from the Phyllium species of these islands. The results show distinct molecular divergence for several populations and suggest the presence of two new cryptic species, morphologically inseparable from Phyllium hausleithneri Brock, 1999. From Sumatra, the population originally thought to be a range expansion for Phyllium hausleithneri, is now here described as Phyllium nisus sp. nov., with the only consistent morphological difference being the color of the eggs between the two populations (dark brown in P. hausleithneri and tan in P. nisus sp. nov.). Further, an additional population with purple coxae from Java was morphologically examined and found to have no consistent features to separate it morphologically from the other purple coxae species. This cryptic species from Java was however shown to be molecularly distinct from the other purple coxae populations from Sumatra and Peninsular Malaysia and is here described as Phyllium gardabagusi sp. nov. In addition, Phyllium giganteum is here officially reported from Java for the first time based on both historic and modern records of male specimens