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1.
Sci Rep ; 14(1): 10447, 2024 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714726

RESUMO

Polyandry, the practice of females mating with multiple males, is a strategy found in many insect groups. Whether it increases the likelihood of receiving beneficial genes from male partners and other potential benefits for females is controversial. Strepsiptera are generally considered monandrous, but in a few species females have been observed copulating serially with multiple males. Here we show that the offspring of a single female can have multiple fathers in two Strepsiptera species: Stylops ovinae (Stylopidae) and Xenos vesparum (Xenidae). We studied female polyandry in natural populations of these two species by analysis of polymorphic microsatellite loci. Our results showed that several fathers can be involved in both species, in some cases up to four. Mating experiments with S. ovinae have shown that the first male to mates with a given female contributes to a higher percentage of the offspring than subsequent males. In X. vesparum, however, we found no significant correlation between mating duration and offspring contribution. The prolonged copulation observed in S. ovinae may have the advantage of reducing competition with sperm from other males. Our results show that monandry may not be the general pattern of reproduction in the insect order Strepsiptera.


Assuntos
Insetos , Repetições de Microssatélites , Comportamento Sexual Animal , Espermatozoides , Animais , Masculino , Feminino , Comportamento Sexual Animal/fisiologia , Espermatozoides/fisiologia , Insetos/fisiologia , Repetições de Microssatélites/genética , Reprodução/fisiologia
2.
Zookeys ; 1178: 39-59, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37692914

RESUMO

A new species of the order Zoraptera, Zorotypuskomatsui Matsumura, Maruyama, Ntonifor & Beutel, sp. nov., is described from Cameroon. The female and male morphology of another species, Z.vinsoni, is re-described, and its new distribution in Madagascar is recorded. A particular focus is on the male postabdominal morphology. This is apparently a crucial body region in the very small order with an extreme variation of the genital apparatus but otherwise a very uniform morphology. The male of the newly described species shares rudimentary male genitalia and well-developed postabdominal projections with the distantly related Spermozorosimpolitus, apparently a result of parallel evolution. Whether males of Z.komatsui also perform external sperm transfer like S.impolitus remains to be shown. The collecting of the material used for this study suggests that the present knowledge of zorapteran species diversity of the Afrotropical region is very fragmentary.

3.
Syst Biol ; 72(5): 1084-1100, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37094905

RESUMO

The spectacular radiation of insects has produced a stunning diversity of phenotypes. During the past 250 years, research on insect systematics has generated hundreds of terms for naming and comparing them. In its current form, this terminological diversity is presented in natural language and lacks formalization, which prohibits computer-assisted comparison using semantic web technologies. Here we propose a Model for Describing Cuticular Anatomical Structures (MoDCAS) which incorporates structural properties and positional relationships for standardized, consistent, and reproducible descriptions of arthropod phenotypes. We applied the MoDCAS framework in creating the ontology for the Anatomy of the Insect Skeleto-Muscular system (AISM). The AISM is the first general insect ontology that aims to cover all taxa by providing generalized, fully logical, and queryable, definitions for each term. It was built using the Ontology Development Kit (ODK), which maximizes interoperability with Uberon (Uberon multispecies anatomy ontology) and other basic ontologies, enhancing the integration of insect anatomy into the broader biological sciences. A template system for adding new terms, extending, and linking the AISM to additional anatomical, phenotypic, genetic, and chemical ontologies is also introduced. The AISM is proposed as the backbone for taxon-specific insect ontologies and has potential applications spanning systematic biology and biodiversity informatics, allowing users to: 1) use controlled vocabularies and create semiautomated computer-parsable insect morphological descriptions; 2) integrate insect morphology into broader fields of research, including ontology-informed phylogenetic methods, logical homology hypothesis testing, evo-devo studies, and genotype to phenotype mapping; and 3) automate the extraction of morphological data from the literature, enabling the generation of large-scale phenomic data, by facilitating the production and testing of informatic tools able to extract, link, annotate, and process morphological data. This descriptive model and its ontological applications will allow for clear and semantically interoperable integration of arthropod phenotypes in biodiversity studies.


Assuntos
Artrópodes , Animais , Filogenia , Insetos , Informática , Biodiversidade
4.
Biol Lett ; 19(3): 20220559, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36855857

RESUMO

Conversion of forewings into hardened covers, elytra, was a ground-breaking morphological adaptation that has contributed to the extraordinary evolutionary success of beetles. Nevertheless, the knowledge of the functional aspects of these structures is still fragmentary and scattered across a large number of studies. Here, we have synthesized the presently available information on the evolution, development, modifications and biological functions of this crucial evolutionary novelty. The formation of elytra took place in the earliest evolution of Coleoptera, very likely already in the Carboniferous, and was achieved through the gradual process of progressive forewing sclerotization and the formation of inward directed epipleura and a secluded sub-elytral space. In many lineages of modern beetles, the elytra have been distinctly modified. This includes multiple surface modifications, a rigid connection or fusion of the elytra, or partial or complete reduction. Beetle elytra can be involved in a very broad spectrum of functions: mechanical protection of hind wings and body, anti-predator strategies, thermoregulation and water saving, water harvesting, flight, hind wing folding, diving and swimming, self-cleaning and burrow cleaning, phoresy of symbiotic organisms, mating and courtship, and acoustic communication. We postulate that the potential of the elytra to take over multiple tasks has enormously contributed to the unparalleled diversification of beetles.


Assuntos
Besouros , Mergulho , Animais , Acústica , Regulação da Temperatura Corporal , Água
5.
J Morphol ; 284(6): e21576, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36930728

RESUMO

The morphology of the adult free-living females of Mengenilla moldrzyki and Eoxenos laboulbenei (Strepsiptera, Mengenillidae) was documented with µCT-based 3D reconstructions and histological serial sections. External and internal features of both species are characterized by far-reaching specialization and structural simplification. The well-developed mandibles are moved by large muscles. Other mouthparts and their corresponding musculature are simplified or absent. The brain is partly shifted into the prothorax. It is followed by a single postcerebral ganglionic complex also containing the subesophageal ganglion and an unpaired abdominal nerve. Postcephalic sclerites are absent, except for the plate-like pronotum and small pleural sclerites. Wings and associated muscles are missing. The lumina of the large midgut and the anterior hindgut are disconnected. Seven bulb-shaped Malpighian tubules in M. moldrzyki is the highest number yet described for Strepsiptera. The 10-segmented abdomen lacks appendages. An unpaired birth organ opens ventrally on abdominal segment VII. The entire body cavity is filled with numerous freely floating eggs, 1386 in the specimen of M. moldrzyki and 721 in E. laboulbenei. Genital ducts, defined gonads, and genital glands are missing. The morphology of female Mengenillidae is discussed with respect to sexual dimorphism and structural features of the postembryonic stages. Phylogenetic implications are outlined.


Assuntos
Insetos , Túbulos de Malpighi , Feminino , Animais , Filogenia , Insetos/anatomia & histologia , Abdome , Músculos/anatomia & histologia
6.
Insect Sci ; 30(5): 1445-1463, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36692245

RESUMO

Dilaridae are a distinctive and phylogenetically ambiguous neuropteran family. So far, the anatomy of the immature stages remains largely unknown. We examined the 1st instar larvae of Dilar montanus in detail and present results of live observations for the first time. The minute, cryptic larvae display features correlated with their underground lifestyle: for instance, a strongly flattened head, stout antennae, eyelessness, and burrowing forelegs. In contrast to molecular data, several characters suggest a 'dilarid clade' combining Dilaridae with Mantispoidea, for instance a very thin and curved or reduced tentorial bridge, and an elongated postmentum. We found intrinsic antennal muscles and Johnston's organ, the first record of these structures in holometabolous larvae. This proves that the first 2 larval antennomeres are homologous with the scapus and pedicellus. The described characters are discussed and analyzed with an updated matrix of neuropteran larval characters. Alternative scenarios of character evolution are presented. Additionally, we show how the 1st-instar larvae move and feed in the substrate, and also provide a high-resolution video recording of the function of the elongate tubular ovipositor and the egg-laying behavior in an adult female under natural conditions.

7.
J Morphol ; 284(1): e21532, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36317298

RESUMO

Platypsyllus castoris is closely associated with beavers and displays a unique set of structural specializations. We document the morphology of adults with modern techniques, and interpret evolutionary changes linked with the specific life style. The small subfamily Platypsyllinae has evolved an entire suite of features correlated with a more or less close association with mammals, for instance a flattened body, a dorsal cephalic shield, flightlessness, eye reduction, and depigmentation. Within this small group, Platypsyllus displays numerous autapomorphic features, correlated with a close association with the beaver. Essential is a combination of mechanical stabilization and firm anchorage on the host, and efficient forward movement in the fur. Exo- and endoskeletal structures of the head and thorax are reinforced by vertical cuticular columns and by an array of internal ridges. The antennae are shortened and strongly modified, the mandibles distinctly reduced and flattened, unsuitable for cutting, scraping or grinding. The musculature of the mouthparts is simplified, whereas an enhanced set of prepharyngeal and pharyngeal dilators forms an efficient sucking pump. The prothoracic musculature is strongly developed. In contrast, the pterothoracic muscle system is distinctly simplified, even though leg muscles are strongly developed. Using the legs, the flattened beetles move sideways through the dense fur of the beaver, using posteriorly directed groups of setae and ctenidia to prevent being pushed backwards by the densely arranged hairs. In contrast to the anterior body, the cuticle of the abdomen is thin, and the entire tagma flexible, with thin layers of segmental muscles. The hind gut is not connected with the mid gut. The beetles probably consume liquid, possibly with emulgated minute skin debris. As the morphology of the mouthparts excludes damage to the skin of the host, the association should not be addressed as ectoparasitic but as commensalism.


Assuntos
Besouros , Animais , Adaptação Fisiológica , Evolução Biológica , Besouros/anatomia & histologia , Mamíferos , Roedores , Simbiose
8.
Arthropod Struct Dev ; 68: 101164, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35468454

RESUMO

The distal leg structures of Zoraptera are documented and discussed with respect to their functional morphology and evolutionary aspects. We investigated eight species using scanning electron microscopy. We analyzed material compositions of the tarsus in three representative species using confocal laser scanning microscopy. When possible, we included both sexes, wing morphs, and nymphs and compared the structures among them. The distal leg structure is unusually uniform across zorapterans regardless of the sex, morphs, and developmental stages. The observed features combine simplification with innovation. The former is likely partially correlated with cryptic microhabitats and miniaturization. Innovation includes a protibial cleaning organ. This is very likely an autapomorphy of Zoraptera. The tarsi are composed of two tarsomeres covered with setae. The pretarsus distally bears an unguitractor plate and well-sclerotized claws. The tarsomeres appear less-sclerotized than the covering setae. The articulation between the basitarsus and tarsomere 2 is hinge-like, implying that tarsomere 2 moves only mediolaterally. The simplified and specialized tarsal morphology is likely suitable for the typical zorapteran microhabitat, under bark. However, the irreversible complete loss of adhesive devices prevented zorapterans to make use of a broader spectrum of environments and was presumably one reason for the species paucity of the group.


Assuntos
Neópteros , Sensilas , Animais , Evolução Biológica , Feminino , Masculino , Microscopia Eletrônica de Varredura
9.
Microorganisms ; 10(2)2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35208711

RESUMO

The Entomophthoromycotina, a subphylum close to the root of terrestrial fungi with a bias toward insects as their primary hosts, has been notoriously difficult to categorize taxonomically for decades. Here, we reassess the phylogeny of this group based on conserved genes encoding ribosomal RNA and RNA polymerase II subunits, confirming their general monophyly, but challenging previously assumed taxonomic relationships within and between particular clades. Furthermore, for the prominent, partially human-pathogenic taxon Conidiobolus, a new type species C. coronatus is proposed in order to compensate for the unclear, presumably lost previous type species C. utriculosus Brefeld 1884. We also performed an exhaustive survey of the broad host spectrum of the Entomophthoromycotina, which is not restricted to insects alone, and investigated potential patterns of co-evolution across their megadiverse host range. Our results suggest multiple independent origins of parasitism within this subphylum and no apparent co-evolutionary events with any particular host lineage. However, Pterygota (i.e., winged insects) clearly constitute the most dominantly parasitized superordinate host group. This appears to be in accordance with an increased dispersal capacity mediated by the radiation of the Pterygota during insect evolution, which has likely greatly facilitated the spread, infection opportunities, and evolutionary divergence of the Entomophthoromycotina as well.

10.
Curr Biol ; 31(15): 3374-3381.e5, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34197727

RESUMO

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.


Assuntos
Âmbar , Besouros , Fósseis , Animais , Besouros/genética , Filogenia
13.
BMC Evol Biol ; 20(1): 64, 2020 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-32493355

RESUMO

BACKGROUND: The latest advancements in DNA sequencing technologies have facilitated the resolution of the phylogeny of insects, yet parts of the tree of Holometabola remain unresolved. The phylogeny of Neuropterida has been extensively studied, but no strong consensus exists concerning the phylogenetic relationships within the order Neuroptera. Here, we assembled a novel transcriptomic dataset to address previously unresolved issues in the phylogeny of Neuropterida and to infer divergence times within the group. We tested the robustness of our phylogenetic estimates by comparing summary coalescent and concatenation-based phylogenetic approaches and by employing different quartet-based measures of phylogenomic incongruence, combined with data permutations. RESULTS: Our results suggest that the order Raphidioptera is sister to Neuroptera + Megaloptera. Coniopterygidae is inferred as sister to all remaining neuropteran families suggesting that larval cryptonephry could be a ground plan feature of Neuroptera. A clade that includes Nevrorthidae, Osmylidae, and Sisyridae (i.e. Osmyloidea) is inferred as sister to all other Neuroptera except Coniopterygidae, and Dilaridae is placed as sister to all remaining neuropteran families. Ithonidae is inferred as the sister group of monophyletic Myrmeleontiformia. The phylogenetic affinities of Chrysopidae and Hemerobiidae were dependent on the data type analyzed, and quartet-based analyses showed only weak support for the placement of Hemerobiidae as sister to Ithonidae + Myrmeleontiformia. Our molecular dating analyses suggest that most families of Neuropterida started to diversify in the Jurassic and our ancestral character state reconstructions suggest a primarily terrestrial environment of the larvae of Neuropterida and Neuroptera. CONCLUSION: Our extensive phylogenomic analyses consolidate several key aspects in the backbone phylogeny of Neuropterida, such as the basal placement of Coniopterygidae within Neuroptera and the monophyly of Osmyloidea. Furthermore, they provide new insights into the timing of diversification of Neuropterida. Despite the vast amount of analyzed molecular data, we found that certain nodes in the tree of Neuroptera are not robustly resolved. Therefore, we emphasize the importance of integrating the results of morphological analyses with those of sequence-based phylogenomics. We also suggest that comparative analyses of genomic meta-characters should be incorporated into future phylogenomic studies of Neuropterida.


Assuntos
Evolução Molecular , Holometábolos/genética , Filogenia , Animais , Sequência de Bases , Genômica , Larva/genética , Análise de Sequência de DNA , Transcriptoma
14.
Arthropod Struct Dev ; 56: 100932, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32375099

RESUMO

Endoparasitic larval stages of Eoxenos laboulbenei were documented with different techniques, with a main focus on the male tertiary larva. Two discrete endoparasitic stages occur, the secondary and the tertiary larva. The presence of large compound eyes and externally visible wing buds in the tertiary larva is a unique feature within Holometabola. The brain with large optic lobes is followed by a single postcephalic ganglionic complex. The cephalic musculature is greatly reduced but pharyngeal dilators and muscles associated with the mouth field are present. Postcephalic sclerites are absent except for the pronotum. The segmented legs bear filiform pretarsal claws. The indirect flight muscles fill up a large part of the metathorax. The 10-segmented abdomen lacks appendages. Pleural folds are present on the thorax and abdomen. The digestive tract is characterized by a very short oesophagus. The large midgut and the narrow hindgut are disconnected. Six short Malpighian tubules are present. Large testes fill out almost the entire abdomen. In contrast to the tertiary larva, the muscles of the secondary larva are not fully differentiated. Cephalic appendages are present as bud-shaped anlagen. The legs lack a pretarsal claw. The developmental transformations are outlined and discussed, also with respect to phylogenetic implications.


Assuntos
Holometábolos/anatomia & histologia , Animais , Croácia , Feminino , Holometábolos/crescimento & desenvolvimento , Larva/anatomia & histologia , Larva/crescimento & desenvolvimento , Masculino
15.
Proc Natl Acad Sci U S A ; 116(49): 24729-24737, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31740605

RESUMO

The order Coleoptera (beetles) is arguably the most speciose group of animals, but the evolutionary history of beetles, including the impacts of plant feeding (herbivory) on beetle diversification, remain poorly understood. We inferred the phylogeny of beetles using 4,818 genes for 146 species, estimated timing and rates of beetle diversification using 89 genes for 521 species representing all major lineages and traced the evolution of beetle genes enabling symbiont-independent digestion of lignocellulose using 154 genomes or transcriptomes. Phylogenomic analyses of these uniquely comprehensive datasets resolved previously controversial beetle relationships, dated the origin of Coleoptera to the Carboniferous, and supported the codiversification of beetles and angiosperms. Moreover, plant cell wall-degrading enzymes (PCWDEs) obtained from bacteria and fungi via horizontal gene transfers may have been key to the Mesozoic diversification of herbivorous beetles-remarkably, both major independent origins of specialized herbivory in beetles coincide with the first appearances of an arsenal of PCWDEs encoded in their genomes. Furthermore, corresponding (Jurassic) diversification rate increases suggest that these novel genes triggered adaptive radiations that resulted in nearly half of all living beetle species. We propose that PCWDEs enabled efficient digestion of plant tissues, including lignocellulose in cell walls, facilitating the evolution of uniquely specialized plant-feeding habits, such as leaf mining and stem and wood boring. Beetle diversity thus appears to have resulted from multiple factors, including low extinction rates over a long evolutionary history, codiversification with angiosperms, and adaptive radiations of specialized herbivorous beetles following convergent horizontal transfers of microbial genes encoding PCWDEs.


Assuntos
Biodiversidade , Evolução Biológica , Besouros/genética , Transferência Genética Horizontal , Genoma de Inseto , Animais , Bactérias/enzimologia , Bactérias/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Parede Celular/química , Parede Celular/metabolismo , Celulases/genética , Celulases/metabolismo , Besouros/enzimologia , Besouros/microbiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fungos/enzimologia , Fungos/genética , Herbivoria/genética , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Lignina/química , Lignina/metabolismo , Filogenia , Plantas/química , Polissacarídeo-Liases/genética , Polissacarídeo-Liases/metabolismo , Polissacarídeos/química , Polissacarídeos/metabolismo
16.
Zootaxa ; 4651(3): zootaxa.4651.3.9, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31716903

RESUMO

A new species of the order Zoraptera, Zorotypus pecten sp. n., is described from mid-Cretaceous Burmese amber. It is tentatively assigned to the subgenus Octozoros based on 8-segmented antenna. A Gondwanan origin for Zoraptera is discussed based on the geographic distribution of extant and fossil zorapterans.


Assuntos
Âmbar , Insetos , Animais , Fósseis , Neópteros
17.
J Morphol ; 280(12): 1742-1758, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31589349

RESUMO

The morphology of mature larvae of Sisyra nigra was studied and documented with a broad spectrum of techniques. Special emphasis is on the cephalic anatomy and on the digestive tract. Cephalic structures are highly modified, with numerous autapomorphic conditions, including a globular head capsule, an extended area with large cornea lenses, a massive tentorium, a strongly developed prepharyngeal pumping apparatus with a horizontal arrangement of dilators, a sharp bend between the prepharynx and pharynx, and an unusual filter apparatus at the entrance of the large crop. The thoracic and abdominal muscle sets, and the legs are largely unmodified. Postcephalic apomorphies are conspicuous tergal setiferous tubercles, trifid setiferous pleural projections, single pretarsal claws, zigzag-shaped abdominal tracheal gills, and a dense vestiture of setae on the terminal abdominal segments. Mandibulo-maxillary stylets curved outwards are an unusual apomorphy also found in the semiaquatic larvae of Osmylidae. Semiaquatic or aquatic habits and secondarily multisegmented antennae are potential synapomorphies of these two groups and Nevrorthidae (Osmyloidea). A sistergroup relationship between Sisyridae and Nevrorthidae suggests that fully aquatic habits of larvae may be a synapomorphy of both families. A specialized terminal antennal seta is a potential groundplan apomorphy of Neuroptera, with secondary loss in Nevrorthidae and Ithonidae + Myrmeleontiformia, respectively. A trumpet-shaped empodium is likely an apomorphy of Neuroptera excluding Coniopterygidae and Osmyloidea, and the secondary loss an apomorphy of Ithonidae on one hand, and Myrmeleontiformia excl. Psychopsidae on the other.


Assuntos
Insetos/anatomia & histologia , Larva/anatomia & histologia , Animais , Filogenia
18.
J Morphol ; 280(8): 1207-1221, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31219651

RESUMO

Leiodidae are the second largest subterranean radiation of beetles at family rank. To explore morphological trends linked with troglobiontic habits and characters with potential phylogenetic significance, the head of the cave-dwelling species Troglocharinus ferreri (Cholevinae, Leptodirini) was examined in detail. Overall, the general pattern is similar to what is found in Catops ventricosus (Cholevini). Shared apomorphic features include a fully exposed anterolateral concavity containing the antennal socket, a distinct bead above this depression, a bilobed lip-like structure anterad the labrum, a flat elevated portion of the ventral mandibular surface, and a ventral process at the proximomesal edge of this mandibular area. The tentorial structures are well-developed as in C. ventricosus, with a large laminatentorium and somewhat shortened dorsal arms. The mouthparts are largely unmodified, with the exception of unusually well-developed extrinsic maxillary muscles. Features of T. ferreri obviously linked with subterranean habits are the complete lack of compound eyes, circumocular ridges, and optic lobes. A series of characters is similar to conditions found in other genera of Leptodirini: the head capsule completely lacks a protruding ocular region, a distinct neck is missing, the transverse occipital crest is indistinct, and the antennae are elongate and lack a distinct club. Two different trends of cephalic transformations occur in troglobiontic Leptodirini, with some genera like Troglocharinus and Leptodirus having elongated head capsules and antennae, and others having broadened, more transverse heads. In contrast, the modifications are more uniform in the closely related Ptomaphagini, with a pattern distinctly differing from Leptodirini: the head is transverse, with a distinctly protruding ocular region, a distinct transverse occipital crest, and a very narrow neck region.


Assuntos
Besouros/anatomia & histologia , Cabeça/anatomia & histologia , Animais , Osso e Ossos/anatomia & histologia , Osso e Ossos/ultraestrutura , Cavernas , Imageamento Tridimensional , Filogenia
19.
J Morphol ; 280(5): 739-755, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30892750

RESUMO

Mengenillidae is a small, basal family of Strepsiptera, mainly characterized by free-living females in contrast to the endoparasitic females of Stylopidia. Here, we describe external and internal structures of the female abdomen of Eoxenos laboulbenei (Mengenillidae). The external morphology was examined and documented using microphotography. Internal structures were reconstructed three-dimensionally using a µCT-data set. The morphologically simplified abdomen comprises 10 segments. The integument is weakly sclerotized and flexible. Spiracles are present dorsolaterally on segments I-VII. Segment VII bears the posteroventral birth opening and the small abdominal segment X carries the anus at its apex. Numerous eggs float freely in the hemolymph. The musculature of segments I-IV is composed of ventral and dorsal longitudinal muscle bundles, strongly developed paramedial dorsoventral muscles and a complex meshwork of small pleural muscles, with minimal differences between the segments. Segments V-X contain more than 50 individual muscles, even though the musculature as a whole is weakly developed. Even though it is not involved in processing food, the digestive tract is well-developed. Its postabdominal section comprises a part of the midgut and the short hindgut. The midgut fills a large part of the postabdominal lumen. The lumina of the midgut and hindgut are not connected. Five or six nodular Malpighian tubules open into the digestive tract at the border region between the midgut and hindgut. The birth organ below the midgut releases the primary larvae after hatching via the birth opening at segment VII. It is likely derived from primary female genital ducts. The presence of six additional birth organs of segments I-VI are de novo formations and a groundplan apomorphy of Stylopidia, the large strepsipteran subgroup with endoparasitic females. The loss of the primary birth organ of segment VII is an apomorphy of Stylopiformia (Stylopidia excl. Corioxenidae).


Assuntos
Abdome/anatomia & histologia , Evolução Biológica , Genitália Feminina/anatomia & histologia , Insetos/anatomia & histologia , Exoesqueleto/anatomia & histologia , Animais , Sistema Digestório/anatomia & histologia , Feminino , Imageamento Tridimensional , Larva/anatomia & histologia , Túbulos de Malpighi/anatomia & histologia , Músculos/anatomia & histologia
20.
Mol Phylogenet Evol ; 135: 270-285, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30822528

RESUMO

The beetle superfamily Dytiscoidea, placed within the suborder Adephaga, comprises six families. The phylogenetic relationships of these families, whose species are aquatic, remain highly contentious. In particular the monophyly of the geographically disjunct Aspidytidae (China and South Africa) remains unclear. Here we use a phylogenomic approach to demonstrate that Aspidytidae are indeed monophyletic, as we inferred this phylogenetic relationship from analyzing nucleotide sequence data filtered for compositional heterogeneity and from analyzing amino-acid sequence data. Our analyses suggest that Aspidytidae are the sister group of Amphizoidae, although the support for this relationship is not unequivocal. A sister group relationship of Hygrobiidae to a clade comprising Amphizoidae, Aspidytidae, and Dytiscidae is supported by analyses in which model assumptions are violated the least. In general, we find that both concatenation and the applied coalescent method are sensitive to the effect of among-species compositional heterogeneity. Four-cluster likelihood-mapping suggests that despite the substantial size of the dataset and the use of advanced analytical methods, statistical support is weak for the inferred phylogenetic placement of Hygrobiidae. These results indicate that other kinds of data (e.g. genomic meta-characters) are possibly required to resolve the above-specified persisting phylogenetic uncertainties. Our study illustrates various data-driven confounding effects in phylogenetic reconstructions and highlights the need for careful monitoring of model violations prior to phylogenomic analysis.


Assuntos
Classificação , Besouros/classificação , Besouros/genética , Genômica , Filogenia , Aminoácidos/genética , Animais , Sequência de Bases , Códon/genética , Genoma , Funções Verossimilhança , Transcriptoma/genética
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