India-Madagascar vicariance explains cascade beetle biogeography Toussaint, Emmanuel F. A.; Fikáček, Martin; Short, Andrew E. Z.
Biological Journal of the Linnean Society/Biological journal of the Linnean Society,
08/2016, Volume:
118, Issue:
4
Journal Article
The species of the genus Dactylosternum Wollaston, 1854 occurring in China and Japan are reviewed. Ten species are recognized to occur in China, two of which were also recorded from Japan. Four new ...species are described from China: Dactylosternum nanlingensis Mai et Jia, sp. nov. (Guangdong, Jiangxi) from fungal hyphae on fallen wood, D. songxiaobini Mai et Jia, sp. nov. (Guangxi) from fallen wood with termites, D. pseudolatum Mai et Jia, sp. nov. (Guangdong, Hubei, Hunan, Jiangxi, Fujian, Hainan, Yunnan) and D. frater Mai et Jia, sp. nov. (Yunnan) from banana trees. Dactylosternum latum (Sharp, 1873) and D. salvazai Orchymont, 1925 are reported for the first time from China, and species recorded previously (D. abdominale (Fabricius, 1792), D. corbetti Balfour-Browne, 1942, D. hydrophiloides (MacLeay, 1825) and D. pui Jia, 2002) are redescribed or diagnosed. Dactylosternum abdominale (Fabricius, 1792) is confirmed to occur in Japan. Dactylosternum latum is only known from Japan based on type specimens believed to be collected in Nagasaki by G. Lewis in late 19th century; since the species was never re-collected in Japan later, its distribution in Japan seems doubtful. Dactylosternum vitalisi Orchymont, 1925 is synonymized with D. latum (Sharp, 1873), the variability of the latter species is discussed. We moreover found that the type series of D. vitalisi contains two species, with some paratypes actually belonging to D. pseudolatum Mai et Jia, sp. nov. All species of Dactylosternum living in China and Japan are diagnosed and illustrated and a key allowing their identification is provided. We infer that the compact antennal club and paralleled body form are characters related to the life inside of plant tissues, while loose antennal club and rounded body form is present in free living Dactylosternum species. The combination of characters for distinguishing Dactylosternum from other genera of Coelostomatini is also provided.
The phylogeny and evolutionary history of the water scavenger beetles (Coleoptera: Hydrophilidae) are inferred from comprehensive analyses of DNA sequence data from the mitochondrial genes COI, COII ...and 16S and the nuclear genes 18S, 28S and arginine kinase. Bayesian and maximum parsimony analyses included 151 taxa, representing all subfamilies, tribes and subtribes that have ever been proposed in the family, as well as representatives of the hydrophiloid families Helophoridae, Hydrochidae, Spercheidae, Epimetopidae and Georissidae. The resulting well‐supported trees strongly disagree with prior classifications of the Hydrophilidae, suggesting that the smaller subfamilies (Horelophinae, Horelophopsinae and Sphaeridiinae) are derived from within the larger Hydrophilinae. The existing tribal classification is more compatible with our results, but many significant differences are evident. Here, we present a new classification of the Hydrophilidae comprising 6 subfamilies and 12 tribes. Each subfamily and tribe is reviewed in detail with (i) a morphological diagnosis, including known or putative morphological synapomorphies, (ii) its taxonomic circumscription, including genera not included in our analyses, and (iii) a review of its general biology and geographic distribution. A new identification key to subfamily and tribe based on adult morphology is also provided. The newly adopted classification requires the following taxonomic changes: the subfamily Hydrophilinae sensu n. is redefined to include only the tribes Amphiopini stat.n. (removed from the synonymy with the Chaetarthriini), Berosini, Laccobiini, Hydrophilini and Hydrobiusini (= Sperchopsini syn.n.); the subfamily Chaetarthriinae stat.n. is removed from synonymy with the Hydrophilinae and includes the tribes Chaetarthriini and Anacaenini (= Horelophinae syn.n.); the Acidocerinae stat.n. (= Horelophopsinae syn.n.) and Rygmodinae stat.n. (= Andotypini syn.n., Borborophorini syn.n. and Tormissini syn.n.) are elevated to subfamily rank; and the subfamily Enochrinae subfam.n. is established for the genus Enochrus and its relatives. The implications for the morphological evolution, ecological transitions and biogeography of the family are discussed.
The Triassic was a crucial period for the early evolution and diversification of insects, including Coleoptera1–3—the most diverse order of organisms on Earth. The study of Triassic beetles, however, ...relies almost exclusively on flattened fossils with limited character preservation. Using synchrotron microtomography, we investigated a fragmentary Upper Triassic coprolite, which contains a rich record of 3D-preserved minute beetle remains of Triamyxa coprolithica gen. et sp. nov. Some specimens are nearly complete, preserving delicate structures of the legs and antennae. Most of them are congruent morphologically, implying that they are conspecific. Phylogenetic analyses suggest that T. coprolithica is a member of Myxophaga, a small suborder of beetles with a sparse fossil record, and that it represents the only member of the extinct family Triamyxidae fam. nov. Our findings highlight that coprolites can contain insect remains, which are almost as well preserved as in amber. They are thus an important source of information for exploring insect evolution before the Cretaceous-Neogene “amber time window.” Treated as food residues, insect remains preserved in coprolites also have important implications for the paleoecology of insectivores, in this case, likely the dinosauriform Silesaurus opolensis.
•The beetle Triamyxa coprolithica is described from a Triassic coprolite•It represents the only member of the extinct myxophagan family Triamyxidae•The coprolite was likely produced by the dinosauriform Silesaurus opolensis•The beetle fossils parallel younger amber inclusions in preservation quality
Qvarnström et al. use synchrotron microtomography to describe 3D-preserved beetle fossils from a Triassic coprolite. Most specimens belong to the new beetle Triamyxa coprolithica, which represents the only member of the extinct myxophagan family Triamyxidae. The fossil dropping was likely produced by the dinosauriform Silesaurus opolensis.
The evolution of the coleopteran suborder Adephaga is discussed based on a robust phylogenetic background. Analyses of morphological characters yield results nearly identical to recent molecular ...phylogenies, with the highly specialized Gyrinidae placed as sister to the remaining families, which form two large, reciprocally monophyletic subunits, the aquatic Haliplidae + Dytiscoidea (Meruidae, Noteridae, Aspidytidae, Amphizoidae, Hygrobiidae, Dytiscidae) on one hand, and the terrestrial Geadephaga (Trachypachidae + Carabidae) on the other. The ancestral habitat of Adephaga, either terrestrial or aquatic, remains ambiguous. The former option would imply two or three independent invasions of aquatic habitats, with very different structural adaptations in larvae of Gyrinidae, Haliplidae and Dytiscoidea.
This study presents the largest set of morphological characters of adults and immature stages ever compiled for the coleopteran suborder Adephaga.
Analyses of the morphological characters yield results nearly identical to recent analyses of molecular data, suggesting that a stable phylogeny has been achieved.
The character transformation on the phenotypic level is reconstructed using a formal approach for the first time, based on the robust phylogenetic pattern and mesquite.
Explaining the disparity of species richness across the tree of life is one of the great challenges in evolutionary biology. Some lineages are exceptionally species rich, while others are relatively ...species poor. One explanation for heterogeneity among clade richness is that older clades are more species rich because they have had more time to accrue diversity than younger clades. Alternatively, disparity in species richness may be due to among-lineage diversification rate variation. Here we investigate diversification in water scavenger beetles (Hydrophilidae), which vary in species richness among major lineages by as much as 20 fold. Using a time-calibrated phylogeny and comparative methods, we test for a relationship between clade age and species richness and for shifts in diversification rate in hydrophilids. We detected a single diversification rate increase in Megasternini, a relatively young and species rich clade whose diversity might be explained by the stunning diversity of ecological niches occupied by this clade. We find that Amphiopini, an old clade, is significantly more species poor than expected, possibly due to its restricted geographic range. The remaining lineages show a correlation between species richness and clade age, suggesting that both clade age and variation in diversification rates explain the disparity in species richness in hydrophilids. We find little evidence that transitions between aquatic, semiaquatic, and terrestrial habitats are linked to shifts in diversification rates.
The Taiwanese fauna of the dung beetle genus Oxyomus Dejean, 1833 (Coleoptera: Scarabaeidae: Aphodiinae) is reviewed based on museum specimens and newly collected material. Four species, all endemic ...to Taiwan, are recognized, one of which is newly described here: O. alligator sp. nov. Remaining species are diagnosed, compared with similar relatives from outside of Taiwan, and their distribution is mapped. We show that Taiwanese Oxyomus species form three distinct morphological groups, similar to species from Japan, SE Asia and Malay Archipelago, respectively, indicating a possible composite origin of Taiwanese fauna. The species occur in submontane and montane forests at altitudes of 700-2550 m including the secondary Cryptomeria ones. Available data confirm their association with dung of various forest mammals (monkeys, muntjacs and serows), although the discovery of larvae in sifted forest leaf litter may indicate they can also develop in nutrient-rich substrate around the dung. The larva of O. alligator sp. nov. is described in detail, based on the larval specimens associated with adults by DNA barcodes. Larvae of Oxyomus alligator sp. nov. are similar to those of the European O. sylvestris (Scopoli, 1763), with important differences only found on maxilla and abdominal apex.
We review the genus Anacaena Thomson, 1859 from the Ryukyu Archipelago, southern Japan. Three aquatic species are recognised: A. torikaii sp. nov. from Amami-ôshima Island, A. okinawana sp. nov. from ...Okinawa-jima Island and Kerama Islands, and A. kumejimana sp. nov. from Kumejima Island. All three species are very similar, with the morphology of the aedeagus being essential for a reliable identification. Dorsal colouration is also useful as a diagnostic character, despite some variation within species. We observe a possible geography-based variation between A. okinawana from Okinawa-jima I. and the neighbouring Kerama Is., but we treat both populations as conspecific based on genital morphology. Anacaena kumejimana and A. okinawana share many morphological characters possibly indicating their close relationship. We compare the endemism of aquatic Hydrophilidae in the Ryukyu Archipelago to that in other groups of aquatic beetles: the proportion of endemic species is higher in aquatic Hydrophilidae than in Dytiscidae, but much lower than in stream-inhabiting Hydraenidae and Elmidae. A list of Japanese species of Anacaena and a key to the Japanese species of the genus are provided.
Abstract
Flea beetles (Alticini) are a diverse lineage of leaf beetles (Coleoptera: Chrysomelidae) with the majority of genera living on vascular plants. However, several genera are associated with ...mosses or leaf litter, as an alternative strategy, often accompanied by changes in morphology and biology. Here, we present the first comprehensive DNA-based phylogenetic analysis of Alticini including 13 moss-inhabiting genera. We show that moss-association is a common phenomenon in Alticini; based on our ancestral-state mapping, we reveal at least nine independent origins of moss-inhabiting, and four independent origins of leaf-litter-inhabiting life-strategy. Our findings illustrate that both cryptic strategies induce parallel evolution of similar ecomorphological adaptations, such as flight loss and a convex body shape. An overview of known moss-inhabiting flea beetle genera is also provided. We describe Benedictoides munclingeri gen. et sp. nov. from the cloud forests of Mount Cameroon, the first flea beetle genus clearly assigned to the moss-inhabiting strategy from tropical Africa. Additionally, our phylogeny provides new insights into the relationships among various flea beetle genera. We estimate six main clades grouping the majority of studied genera, and propose several new generic groups. Along with our phylogenetic results, we discuss moss-inhabiting flea beetle evolution and perspectives of their systematics.
Type specimens from the collection of the polyneopteran insect orders (Dermaptera, Blattodea, Orthoptera, Phasmatodea) deposited in the Department of Entomology, National Museum, Prague are ...catalogued. We provide precise information about types of 100 taxa (5 species of Dermaptera, 3 species of Blattodea, 4 species of Phasmatodea, 55 species of Caelifera, and 33 species of Ensifera), including holotypes of 38 taxa. The year of publication of Calliptamus tenuicercis anatolicus Maran, 1952 and Calliptamus tenuicercis iracus Maran, 1952 are corrected. The authorship of the names traditionally ascribed to J. Obenberger is discussed in detail. Only the name Podisma alpinum carinthiacum Obenberger, 1926 is available since the publication by OBENBERGER (1926a). 'Stenobothrus (Stauroderus) biguttulus ssp. masculineordinal bicolor Charp. 1825' and 'Stenobothrus (Stauroderus) ssp. masculineordinal collinus Kamy' sensu OBENBERGER (1926a,b) refer to Gryllus bicolor Charpentier, 1825 and Stauroderus biguttulus var. collina Karny, 1907, respectively, which both have to be considered available already since their original descriptions by CHARPENTIER (1825) and KARNY (1907).