Neoteny
Dotaz
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- MeSH
- fylogeneze MeSH
- larva MeSH
- morfogeneze MeSH
- rostliny MeSH
- vývojová biologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
We demonstrate the controversial origin of a biological species within an area of a few kilometres in the absence of physical barriers. We employed nuclear rRNA/mitochondrial and genome-wide SNP approaches to infer relationships of four species of net-winged beetles characterised by female neoteny. Three species are distributed at low elevations and a single population colonised a 40 km(2) highland plateau and established distinct biological species despite incomplete genetic isolation. The speciation process is extreme in the highly localised spatial scale, due to the low dispersal power of neotenics, and provides clear support for a microallopatric model based on ecological conditions. In contrast with neutral evolution in a homogenous environment, as demonstrated by the genetic divergence and morphological similarity of two widely distributed low-mountain species, the environmental characteristics of the high-mountain plateau led to the origin of a species adapted to the local mimetic pattern and characterised by morphologically distinct genitalia. We conclude that the low dispersal propensity promotes neutral genetic differentiation in the first stage, but environmental characteristics play an important role the final phase of the speciation process. The unexpected speciation at such an extreme geographic scale points to the in situ origin and uniqueness of the mountain fauna.
- MeSH
- biologická evoluce * MeSH
- brouci genetika fyziologie MeSH
- druhová specificita MeSH
- ekosystém * MeSH
- fylogeneze MeSH
- jednonukleotidový polymorfismus genetika MeSH
- sekvenční analýza DNA MeSH
- tropické klima * MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Beetles are the most species-rich animal radiation and are among the historically most intensively studied insect groups. Consequently, the vast majority of their higher-level taxa had already been described about a century ago. In the 21st century, thus far, only three beetle families have been described de novo based on newly collected material. Here, we report the discovery of a completely new lineage of soft-bodied neotenic beetles from the Brazilian Atlantic rainforest, which is one of the most diverse and also most endangered biomes on the planet. We identified three species in two genera, which differ in morphology of all life stages and exhibit different degrees of neoteny in females. We provide a formal description of this lineage for which we propose the new family Jurasaidae. Molecular phylogeny recovered Jurasaidae within the basal grade in Elateroidea, sister to the well-sclerotized rare click beetles, Cerophytidae. This placement is supported by several larval characters including the modified mouthparts. The discovery of a new beetle family, which is due to the limited dispersal capability and cryptic lifestyle of its wingless females bound to long-term stable habitats, highlights the importance of the Brazilian Atlantic rainforest as a top priority area for nature conservation.
- MeSH
- brouci genetika MeSH
- deštný prales MeSH
- ekosystém MeSH
- fylogeneze MeSH
- genetická variace MeSH
- sekvenční analýza DNA MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Brazílie MeSH
The ongoing exploration of biodiversity and the implementation of new molecular tools continue to unveil hitherto unknown lineages. Here, we report the discovery of three species of neotenic beetles for which we propose the new family Iberobaeniidae. Complete mitochondrial genomes and rRNA genes recovered Iberobaeniidae as a deep branch in Elateroidea, as sister to Lycidae (net-winged beetles). Two species of the new genus Iberobaenia, Iberobaenia minuta sp. nov. and Iberobaenia lencinai sp. nov. were found in the adult stage. In a separate incidence, a related sequence was identified in bulk samples of soil invertebrates subjected to shotgun sequencing and mitogenome assembly, which was traced to a larval voucher specimen of a third species of Iberobaenia Iberobaenia shows characters shared with other elateroid neotenic lineages, including soft-bodiedness, the hypognathous head, reduced mouthparts with reduced labial palpomeres, and extremely small-bodied males without strengthening structures due to miniaturization. Molecular dating shows that Iberobaeniidae represents an ancient relict lineage originating in the Lower Jurassic, which possibly indicates a long history of neoteny, usually considered to be evolutionarily short-lived. The apparent endemism of Iberobaeniidae in the Mediterranean region highlights the importance of this biodiversity hotspot and the need for further species exploration even in the well-studied European continent.
- MeSH
- brouci anatomie a histologie klasifikace genetika fyziologie MeSH
- fylogeneze MeSH
- mitochondriální DNA MeSH
- sekvenční analýza DNA metody MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Španělsko MeSH
All life stages of Mortogenesia mesopotamica (Morton, 1921) are described, on the basis of material collected in the lower Euphrates-Tigris River basin. Adults are redescribed, and larvae are described for the first time, based on sets of larval exuviae. The monotypic genus Mortogenesia Lestage, 1923 is redefined using both adult and larval characteristics: eyes not contiguous, distinctly separated by a wide gap; vestigial mandibular tusks present, with 3-4 rounded lateral projections; forewing veins MP1 and iMP not brought together; CuA furcation absent on forewing; both claws similarly shaped in males; hind tarsi five-segmented; penes with roughly triangular, apically rounded and divergent lobes (in adults); seven conspicuous stout teeth on outer margin of mandibular tusk, with no apical spine-like setae; maxillary palps two-segmented; distal segment of labial palps asymmetric and bulbous; basal segment of labial palps densely pilose; forelegs with relatively short, triangular claws that are basally wider than tarsi; foretibiae with stout spines only; and a simple, leaf-like gill 1 (in larvae). The burrowing larvae of M. mesopotamica occur solely in large permanent lowland rivers, in clayey or muddy sediments, with particles exceeding 0.025-0.075 mm. Based on observations of their burrows, larval density is approximately 100-200 individuals per square meter. Various evidence suggests a unique phenomenon of male neoteny in Mortogenesia. Preliminary results of male dissections suggests a missing teneral adult cuticle, and male "subimagoes" and females occur simultaneously after oviposition. Mortogenesia mesopotamica is known currently from the Euphrates-Tigris basin in Iraq and from the Karkheh River in Iran.
- MeSH
- hmyz anatomie a histologie klasifikace MeSH
- larva MeSH
- nymfa MeSH
- pohlavní orgány anatomie a histologie MeSH
- řeky MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Irák MeSH
- Írán MeSH
Elateriformia consists of Dascilloidea, Buprestoidea (jewel beetles), Byrrhoidea and Elateroidea (click beetles, fireflies and relatives). Numerous elateroid lineages contain taxa with modified metamorphosis resulting in sexual maturity while retaining larval characters. Additionally, they evolved unique defensive strategies including clicking mechanism, aposematic coloration and bioluminescence. To investigate the phylogenetic position of Elateroidea within Coleoptera, we merged 1048 newly produced 18S rRNA, 28S rRNA, rrnL mtDNA, and cox1 mtDNA sequences for ∼300 elateriform taxa with data from GenBank. The 975-taxa dataset aligned in BlastAlign was analyzed under maximum likelihood criterion. The results agreed in most aspects with the current morphology-based classification and results of molecular studies. Elateriformia were monophyletic and Elateroidea were sister to Byrrhoidea. Further, we analyzed all-data (513 elateriform taxa) and pruned matrix (417 elateriform taxa, all fragments present) using parsimony and maximum likelihood methods to reveal the phylogenetic relationships among elateroid lineages and examine the evolution of soft-bodiedness, neoteny and bioluminescence. We confirmed the monophyly of Elateroidea sensu lato and most of the families, with Telegeusidae inferred in most trees within paraphyletic Omethidae. The clade Artematopodidae+Telegeusidae+Omethidae was a sister to remaining elateroids. All topologies reject the relationships of hard-bodied Elateridae, Eucnemidae, Throscidae and Cerophytidae, formerly supposed to be a monophylum. Eucnemidae and Throscidae formed independent lineages and the position of Cerophytidae was variable - either a sister to Throscidae, or an independent lineage. The Lampyridae+Cantharidae clade was in most trees sister to Phengodidae+Rhagophthalmidae+Omalisidae+Elateridae. Molecular phylogeny of Elateroidea confirmed the multiple origins of soft-bodied, neotenic and light emiting lineages. On the basis of our molecular phylogeny, we place former Telegeusidae as a subfamily in Omethidae.
- MeSH
- brouci anatomie a histologie klasifikace genetika MeSH
- fylogeneze * MeSH
- geny rRNA genetika MeSH
- luminiscence MeSH
- mitochondriální DNA genetika MeSH
- nejistota MeSH
- sekvence nukleotidů MeSH
- sekvenční analýza DNA MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH