ABSTRACT
In order to place newly discovered fossil taxa (Palaeosymbius gen. nov. with P. groehni and P. mesozoicus spp. nov.) from the mid-Cretaceous amber from northern Myanmar, we investigated the relations of extant and extinct lineages of the coccinellid group of Coccinelloidea with emphasis on the family Anamorphidae. We assembled a taxonomic sampling of 34 taxa, including 15 genera and 19 species of Anamorphidae, the most comprehensive sampling of Anamorphidae at the generic level in a phylogenetic analysis. A morphological dataset of 47 characters was built as well as a molecular alignment of 7140 bp including fragments of eight genes (12S, 16S, 18S, 28S, COI, COII, H3 and CAD). Five anamorphid and one endomychid species were sequenced for the first time and added to the dataset. We performed parsimony-based analysis of the morphological dataset and Bayesian inference analysis of the combined matrix (morphological plus molecular data). Our results confirm that Palaeosymbius belongs to Anamorphidae and represents the oldest known member of this family so far. Among Anamorphidae, Symbiotes (with extant and known Eocene species) was recovered as the most probable closest relative of Palaeosymbius. Our morphological studies additionally revealed the presence of probable glandular openings in the anterolateral corners of the pronotal margins in Asymbius sp. and Anamorphus sp., representing the first report of secretory openings in the family Anamorphidae. Similar openings are found in other cucujiform beetles such as Cryptophagidae and Boganiidae with possible defensive purposes.
Subject(s)
Amber , Coleoptera , Fossils , Phylogeny , Animals , Myanmar , Coleoptera/anatomy & histology , Coleoptera/classification , Coleoptera/genetics , Biological EvolutionABSTRACT
A new genus and species of the family Endomychidae (Coleoptera: Coccinelloidea): Cretostenotarsus striatus Tomaszewska, Szawaryn and Arriaga-Varela gen. et sp. nov. are described, diagnosed and illustrated from the mid-Cretaceous amber from northern Myanmar. To test the systematic placement of the new extinct genus and species within the family, a phylogenetic analysis was conducted. A dataset of 38 morphological characters scored for 29 species (including the new fossil taxon), members of Endomychidae sensu stricto and representatives of Coccinelloidea as outgroups were analyzed using maximum parsimony. The results of the analysis indicate unequivocally that Cretostenotarsus striatus is a member of the Stenotarsus clade within a monophyletic 'endomychine complex' sensu Robertson et al. (2015), which corresponds to 'Higher Endomychidae' sensu Tomaszewska (2005). The present discovery confirms at least the Jurassic origin of Coccinelloidea and indicates a much older origin of Endomychidae than previously hypothesized.
ABSTRACT
The Hydrophilus (Dibolocelus) Bedel species from Mexico and adjacent areas are treated on the basis of the study of 142 adult specimens and published data. Two new species are herein recognized and described: H. (D.) nucleoensis Arce-Prez Arriaga-Varela sp. nov. from Mexico, Guatemala and Nicaragua, H. (D.) pseudovatus Arce-Prez Arriaga-Varela sp. nov. from Mexico. Three already known species are re-described and their geographical distribution is updated, H. (D.) ovatus Gemminger Harold and H. (D.) pollens Sharp and H. (D.) violaceonitens Jacquelin du Val, a species resurrected as distinct to H. (D.) smaragdinus. Hydrophylus (D.) cf. purpurascens (Rgimbart) is also redescribed but their identity is questionable. The lectotype of H. (D.) pollens Sharp is designated. Within Mexico, the state with the highest known diversity is Veracruz with five species. A key to the species of Hydrophilus (Dibolocelus) from Mexico and Central America is provided.
Subject(s)
Coleoptera , Animal Distribution , Animals , Mexico , WaterABSTRACT
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.
Subject(s)
Amber , Coleoptera , Fossils , Animals , Coleoptera/genetics , PhylogenyABSTRACT
Two new species of Megarthrus are described from cloud forests of the Mexican state of Veracruz: M. cavianae Rodríguez, Navarrete-Heredia Arriaga-Varela sp. nov., and Chiapas: M. chiapas Cuccodoro sp. nov. They differ from the two hitherto known Mexican species M. altivagans Bernhauer, 1929, and M. alatorreorum Rodríguez Navarrete-Heredia, 2015, both from temperate forests of the Transmexican Volcanic Belt, by having synapomorphic features of the M. inaequalis-supergroup of species. This lineage includes all the Central and South American members of the genus, with the inclusion of these species, the distribution of the group is extend by more than 5 degree of latitude to the North. Within this lineage, the two new species share a very peculiar morphology of the male abdominal sternite VIII found elsewhere in the genus only in M. flavosignatus Bierig, 1940, and M. zunilensis Sharp, 1887, with which they form the M. zunilensis-group of species defined here.
Subject(s)
Coleoptera , Animal Distribution , Animal Structures , Animals , Body Size , Forests , Male , Mexico , Organ SizeABSTRACT
Intensive survey of museum collections and new field collecting resulted in discovery of six new, closely related species of the Neotropical Merophysiinae. A new species of the genus Lycoperdinella Champion, L. boliviensissp. n., from Bolivia and Brazil, and five new species from Mexico for which a new genus is proposed here as Rueckeriagen. n.: R. inecol (type species), R. nigrileonis, R. ocelotl, R. puma, R. skelleyispp. n., have been discovered. Lycoperdinella, Rueckeriagen. n., L. subcaeca Champion and all new species are diagnosed, described, and illustrated. Keys to the species of Lycoperdinella and Rueckeria and a distribution map are provided. A lectotype of Lycoperdinella subcaeca Champion, 1913 is designated. Molecular barcodes of three new species of Rueckeria are provided in order to help with the identification of these taxa.
ABSTRACT
The representatives of the genus Cercyon Leach occurring in the Greater Antilles are reviewed. Ten species are recorded, of which five are described here as new: C. gimmelisp. n. (Dominican Republic), C. armatipenissp. n. (Dominican Republic), C. tainosp. n. (Dominican Republic), C. sklodowskaesp. n. (Jamaica) and C. spiniventrissp. n. (Dominican Republic). Diagnoses and detailed distributional data are also provided for C. floridanus Horn, 1890 (distributed in southeastern United States of America and Cayman Islands), C. insularis Chevrolat, 1863 (endemic to the Antilles) C. praetextatus (Say, 1825) (widely distributed in the New World incl. Greater Antilles), C. quisquilius (Linnaeus, 1761) (an adventive species of Paleartic origin) and C. nigriceps (Marshall, 1802) (an adventive species probably of Oriental origin). Cercyon armatipenis, C. gimmeli, C. taino form a group of closely related species only distinguishable by male genitalia and DNA sequences. A key to the Great Antillean Cercyon is provided and important diagnostic characters are illustrated. The larvae of C. insularis and C. taino were associated with adults using COI barcode sequences, illustrated and diagnosed. Full occurrence data, additional images and COI barcode sequences were submitted to open access on-line depositories in an effort to provide access to complete data.
ABSTRACT
Endomychidae or Handsome Fungus Beetles are a moderately large family of mycophagous beetles distributed worldwide but with the highest diversity in the tropics (Shockley et al. 2009a, b). The concept of the family (e.g. Lawrence & Newton 1995; Tomaszewska 2000, 2010; Shockley et al. 2009a) has recently been restricted by an elevation of former subfamilies Eupsilobiinae, Mycetaeinae and Anamorphinae to the level of independent families in the newly recognized superfamily Coccinelloidea (Robertson et al. 2015).
Subject(s)
Coleoptera/classification , Coleoptera/ultrastructure , Animal Distribution/physiology , Animals , Brazil , Coleoptera/physiology , Female , Microscopy, Electron, Scanning , Species SpecificityABSTRACT
Electribius relictus sp. nov. (Artematopodidae) is described from a cloud forest fragment in central Veracruz, Mexico. This species is distinguished from the other extant species known, E. crowsoni Lawrence (Mexico) and E. similis Lawrence (El Salvador), by the pronotum and elytra completely black, pronotum with margins crenulate at base, fifth abdominal ventrite with distinct median ridge, and the shape of aedeagus. The new species is illustrated and a key for the identification of extant species of the genus and ecological data for the collecting site are provided.
Subject(s)
Coleoptera/classification , Animal Distribution , Animal Structures/anatomy & histology , Animal Structures/growth & development , Animals , Body Size , Coleoptera/anatomy & histology , Coleoptera/growth & development , Male , Mexico , Organ SizeABSTRACT
A preliminary review of the species of Stenotarsus Perty from México, Guatemala and Belize is presented. Twenty-seven species are recorded from the region including 12 new species described here: Stenotarsus cortesi sp. nov. (Jalisco), S. incisus sp. nov. (Quetzaltenango, Chiapas, Oaxaca, Veracruz), S. kafkai sp. nov. (Veracruz), S. mesoamericanus sp. nov. (Chiapas, Puebla), S. mexicanus sp. nov. (Veracruz), S. molgorae sp. nov. (Jalisco), S. monterrosoi sp. nov. (Izabal), S. parallelicornis sp. nov. (Veracruz), S. raramuri sp. nov. (Durango, Jalisco), S. rulfoi sp. nov. (Jalisco), S. shockleyi sp. nov. (Veracruz), S. spiropenis sp. nov. (Jalisco). Stenotarsus circumdatus Gerstaecker, S. discipennis Gorham and S. tarsalis Gorham are synonymized with S. globosus Guérin-Méneville. Stenotarsus distinguendus Arrow is synonymized with S. sallaei Gorham. Stenotarsus pilatei Gorham is synonymized with S. militaris Gerstaecker. Lectotypes are designated for: Stenotarsus circumdatus Gerstaecker, Stenotarsus distinguendus Arrow, Stenotarsus exiguus Gorham, Stenotarsus globosus Guérin-Méneville, Stenotarsus guatemalae Arrow, Stenotarsus discipennis Gorham, Stenotarsus lemniscatus Gorham, Stenotarsus militaris Gerstaecker, Stenotarsus rubrocinctus Gerstaecker, Stenotarsus sallaei Gorham, Stenotarsus tarsalis Gorham, Stenotarsus thoracicus Gorham. A key to the species in this region is provided. Species are described in detail and illustrated, and habits and habitats are given when available.