Search Results (363)

Scale insects, which belong to the superfamily Coccoidea within the order Hemiptera, encompass more than 8000 species worldwide. The adult females of these species are characterized by their immobility, and often lack wings and legs. Scale insects feed on plant tissues and can cause significant agricultural damage as pests. This study presents the sequencing of five coccoid mitogenomes, revealing detailed annotations and comparisons with other Hemiptera. The sequencing yielded between 73 million and over 121 million reads, allowing for the reconstruction of mitogenomes ranging from 12,821 to 14,446 nucleotides. Notably, a high A + T content was observed across the newly sequenced mitogenomes. Gene rearrangements were identified in all five newly sequenced mitogenomes, with the evolutionary rate analysis indicating that Coccoidea exhibit the highest Ka and Ka/Ks values among the hemipterans. In a phylogenetic context, the mitogenomes of representative species from Coccoidea and Aleyrodoidea exhibit more frequent mitochondrial gene rearrangements than those of other hemipteran groups. The analysis suggests that the frequent mitochondrial gene rearrangements observed in the coccoid species are associated with accelerated nucleotide substitution rates, supporting a connection between genetic evolution and structural variation in mitogenomes. Full article

Recent updates to the reconstructions of Cenozoic environmental changes (global sea level, temperature, and atmospheric carbon dioxide content) have made it intriguing to compare them to paleontological records for original interpretations. Paleogene brachiopods have remained in the shadow of their Paleozoic–Mesozoic predecessors, and the reactions of their diversity to the Earth’s dramatic changes are poorly understood. The present work aims to fill this gap via a comparison of several diversity and paleoenvironmental curves. The generic diversity was established by stages with two essentially different paleontological datasets, and several fresh paleoenvironmental reconstructions were adopted. It was observed that neither Paleogene eustatic fluctuations nor changes in the atmospheric carbon dioxide content correspond well to the generic diversity dynamics of brachiopods. The changes in the total number of genera and the global temperatures demonstrate similarity at the Danian–Ypresian interval, but not later. The fluctuations in the brachiopod diversity are near the same level during the Eocene–Oligocene, despite strong paleoenvironmental changes, implying the intrinsic resistivity of these organisms to external influences. Additionally, the Cretaceous/Paleogene mass extinction, the Paleocene–Eocene thermal maximum, and the Early Eocene optimum could enhance the diversity dynamics together with the long-term temperature changes. In contrast, the influences of the Late Danian warming event and the Oi-1 glaciation were not observed. Full article

Bivalves are nowadays represented by several thousand species of variable sizes and shapes. Additionally, thousands more species occurred during their 500-million-year long evolution. Present on Earth since the Cambrian, the class Bivalvia experienced periods of gradual evolution, interspersed with periods of rapid changes. Some groups of bivalves, namely clams, oysters, scallops, and marine mussels, managed to survive a series of extinctions, and their descendants still thrive in modern oceans and seas. Other groups, such as the rudists, completely disappeared from marine environments, after undergoing successful evolutionary radiation. In this study, we consider the possible reasons for the longevity of some bivalve orders and discuss the possible causes of demise of several once-successful clades. As expected, a small body size, large number of specimens, infaunal mode of life, motility, and long-living planktonic larvae proved to be evolutionary advantages during stress periods. The ability to harbor chemosymbionts could be an additional benefit during biotic crises. Full article

Due to the potential role of Auchenorrhyncha in the transmission of the bacterium Xylella fastidiosa in a wide variety of cultivations, during recent years in Europe, many studies have focused on species composition, abundance and seasonal appearance of Auchenorrhyncha. However, females and nymphs are difficult to identify, as species-level identification relies primarily on male genitalia morphology. Sampling was conducted over four years in olive fields in Lesvos Island, in the Northeast Aegean, Greece, using sweep nets and Malaise traps. Both adults and nymphs were collected, with males identified to species level, while females and nymphs were separated on different morphotypes. Representatives from each morphotype and identified adults were sequenced using the mitochondrial cytochrome oxidase subunit I (COI) gene. Using a classical morphological approach, 58 species were identified to species level, and using DNA barcoding, nymph morphotypes and females were successfully identified within the families Cicadellidae, Aphrophoridae, Delphacidae and Issidae. A phylogenetic tree was generated, clustering nymphs together with the corresponding adults. Our results demonstrate the utility of combining morphological and molecular methods for accurate species identification and highlight the importance of enriching online databases with additional species records. Full article

Insect mitochondrial genomes are vital to understanding evolutionary relationships and identifying species. This study focused on Microtendipes (Chironomidae), a genus with unresolved phylogenetic positioning and cryptic species challenges. We sequenced and analyzed eight mitogenomes from five Microtendipes species, integrating 23 published Chironominae mitogenomes to reconstruct phylogenies using Maximum Likelihood and Bayesian Inference. The mitogenomes exhibited conserved gene arrangements but variable control region lengths (338–1266 bp) and high AT content (94.14–96.42% in control regions). Our results show that Microtendipes species may be a separate group within the subfamily, while also supporting the monophyly of the Harnischia, Polypedilum, and Chironomus complexes. The monophyly of Microtendipes bimaculus was weakly supported, which may demonstrate the presence of two potential cryptic species. Notably, larval morphology-based species groupings conflicted with the molecular data, suggesting that classifications derived from larval morphological traits may be unreliable. This study advances the evolutionary understanding of Chironomidae and underscores the limitations of single-gene barcodes in species-rich genera. Full article

Eighteen flea species of four genera associated with bats (Chiroptera: Vespertilionidae, Rhinolophidae, Miniopteridae, Molossidae) are registered in Russia, based on a literature review as well as our own data. They are as follows: Myodopsylla trisellis, Ischnopsyllus (Ischnopsyllus) dolosus, Ischnopsyllus (I.) elongatus, Ischnopsyllus (I.) intermedius, Ischnopsyllus (I.) plumatus, Ischnopsyllus (I.) needhami, Ischnopsyllus (I.) obscurus, Ischnopsyllus (I.) octactenus, Ischnopsyllus (I.) simplex, Ischnopsyllus (I.) variabilis, Ischnopsyllus (Hexactenopsylla) hexactenus, Ischnopsyllus (H.) petropolitanus, Ischnopsyllus (H.) ussuriensis, Ischnopsyllus (H.) comans, Nycteridopsylla pentactena, Nycteridopsylla longiceps, Nycteridopsylla eusarca, Rhinolophopsylla unipectinata unipectinata. Ischnopsyllus (I.) elongatus and Ischnopsyllus (I.) octactenus were recorded in Kaluga Region and Vladimir Region for the first time. Ischnopsyllus (I.) variabilis in Kaluga Region is a newly documented find. Studied bat flea fauna exhibits a distinctly Western Palearctic appearance. Full article

Natural history collections serve science and society in a variety of ways. Collections of geological, including paleontological, materials are of special importance in the 21st century, as they serve not only as repositories for scientific research specimens, but are also used in teaching, outreach, and engaging the public in science. These collections link us to our scientific, technological, and cultural history, and help to inspire the next generations of scientists and technologists. In addition, they provide inspiration for creative works. They also have an important role in informing public policy and national security, as geological materials are fundamental to the global economy. Examples from universities, museums, and government agencies in central Ohio, USA, help to illustrate the myriad ways that geological collections are relevant to modern society, and provide continuing, critical benefits. These examples reinforce the need to ensure the long-term support of collections. Full article

Tropidia, a type genus of Tropidieae (Orchidaceae, Epidendroideae), represents an important lineage for investigating plastome evolution and phylogenetic relationships within Epidendroideae. Despite its importance, the lack of available plastid genomic data has hindered comprehensive analyses of its genome structure and phylogenetic relationships. In this study, we assembled and characterized the complete plastid genomes of Tropidia angulosa and T. nipponica, providing valuable insights into plastome evolution and phylogenetic placement of Tropidieae. The plastomes of T. angulosa and T. nipponica exhibited a highly conserved quadripartite structure, sharing similar genomic size (161,395 bp and 160,801 bp) and GC content (36.87% and 36.90%). Both plastomes contained identical gene content and gene order, with 79 protein-coding genes (PCGs), 30 tRNA genes, and four rRNA genes. A total of 169 simple-sequence repeats (SSRs) and 92 long-sequence repeats (LSRs) were identified, most of which were distributed in large single-copy (63.91% and 66.30%) and non-coding regions (83.43% and 65.22%). Comparative plastomes analyses revealed the overall structural stability among photosynthetic lineages, whereas structural variation was primarily detected in mycoheterotrophic lineages. Phylogenomic reconstruction based on plastid-coding sequences revealed that Tropidieae occupies a relatively isolated phylogenetic position within Epidendroideae. These findings contribute to a more comprehensive understanding of plastome evolution and the phylogenetic framework of Epidendroideae. Full article

John Strong Newberry described three species of the lobe-fin fish Onychodus (Osteichthyes, Sarcopterygii, Onychodontida) based on parasymphysial teeth, or tusks. Two species, Onychodus sigmoides Newberry, 1857 (type species of the genus) and Onychodus hopkinsi Newberry, 1857, were described from the “fish beds” in the Delaware Limestone (Middle Devonian, Eifelian) of Delaware, Ohio, USA; and one species, Onychodus ortoni Newberry, 1889, was described from the Ohio Shale, Huron Member (Upper Devonian, Famennian) of Perry Township, Franklin County, Ohio. In 1873, Newberry replaced the original species-group definition of O. hopkinsi with a definition based on teeth of different morphology from the West Falls Group (Upper Devonian, Frasnian) of Franklin, New York. Specimens of Newberry’s original Onychodus material, including the primary types, which were long assumed to be lost, have been rediscovered in a 19th-century collection. They show O. hopkinsi to be a junior synonym of O. sigmoides and clarify the species definition of O. sigmoides. Onychodus sigmoides, which is recognized from Middle Devonian strata of the Appalachian Basin in the United States and Canada, shows two end-member shapes of teeth on the parasymphysial whorl: procurved (arcuate) or nearly so proximally and recurved distally (anteriorly). Small teeth are commonly more slender than large teeth, which are robust. Parasymphysial teeth from the Upper Devonian of Ohio and New York are referred to O. ortoni. Full article

A large data set of new and previously published measurements of δ¹³C values derived from tooth enamel (n = 223, of which 93 are new) are compiled to explore patterns of foraging area preferences of Late Cretaceous mosasaurid squamates over evolutionary time scales (~93–66 Ma). Our results indicate that small-bodied halisaurines are restricted to a relatively nearshore range, overlapping the lower end of the range of plioplatecarpines and some mosasaurine taxa. Most moderately sized plioplatecarpines occupy a relatively narrow foraging area in much of the nearshore and proximal offshore marine foraging area for the majority of their existence. Tylosaurines exhibit a greater offshore marine range than plioplatecarpines, consistent with their large body size and the robustness of their feeding apparatus. The largest tylosaurine taxa are replaced by Mosasaurus in the Late Campanian–Maastrichtian in the offshore foraging range. Mosasaurine taxa are found to occupy the broadest range of foraging areas, but their ranges are taxonomically segregated, consistent with adult body size and the diversity of feeding adaptations such as tooth morphologies and skull architecture seen in that subfamily. Where foraging areas of multiple taxa overlap, differences are typically in tooth form, reflecting prey preference or feeding niche. Foraging area occupation by multiple taxa with similar tooth forms suggests that other factors such as body size and prey acquisition style may have allowed for the finer partitioning of resources. Deep diving and long submergence may have also contributed to the depleted signals recovered for some of the large-bodied durophages and the largest of the macrophagous apex predators. Full article

Mosasaur taxa recovered from the Bearpaw Formation, Alberta, Canada, generally show exceptional preservation after rapid burial. Since the mosasaur community consisted of two dominant taxa, Mosasaurus missourensis Prognathodon overtoni, and three less prevalent taxa Tylosaurus proriger, Mosasaurus conodon, and Plioplatecarpus primaevus, some form of habitat or dietary niche partitioning is to be expected. To test this, several approaches are tried. Two-dimensional microwear analysis is used as an exploratory method to quantify tooth abrasion by food items. The good preservation of skull material reveals complete tooth rows of the upper and lower jaws for Mosasaurus missouriensis and Prognathodon overtoni, as well as isolated teeth for all taxa. The teeth are also measured for tooth bending strength to test stress regarding usage of teeth per taxon. Energy-dispersive X-ray spectroscopy (EDX) measurements show trace elements which may be a preliminary test for relative trophic level positioning. Some mosasaurs have their stomach contents preserved, providing direct and unambiguous evidence of diet. The results show a relatively clear separation of two-dimensional microwear counts between Mosasaurus, Prognathodon, and Plioplatecarpus, which, to some extent, is reflected in the EDX analyses, too. Tooth bending strength measurements show a clear difference between the latter three mosasaurs but no difference between the lower and upper jaws in Mosasaurus or Prognathodon. The combination of these three techniques maps a clear dietary niche differentiation of Bearpaw mosasaurs, which lays the groundwork for future analytical or chemical palaeoecological studies. Full article

The arrival of psittacine in North America is well known but undefined. It is widely accepted that these birds originated in South America, and it has been suggested that different factors have promoted the biodiversity of birds in Mexico. However, in general, for North American psittacine, there are no proposed divergence times, and the possible influence of different geological events on these processes is unknown. In this study, phylogenetic relationships, divergence times, and ancestral areas of the genera Aratinga, Eupsittula, and Psittacara and related genera were estimated to propose hypotheses of the origin, diversification, and dispersal of groups under a Bayesian inference framework based on mitochondrial molecular markers. Of seven monophyletic clades within the Arini tribe, four coincided with the genera Psittacara, Eupsittula, Rhynchopsitta, and Pyrrhura, while Aratinga was grouped with Conuropsis and Cyanopsitta. Diversification of the analyzed genera probably occurred during the Miocene and around the Miocene–Pliocene boundary. The results suggest that the most likely origin of these genera is the Amazonian or Chaco regions. The diversification of these groups seems to be related to geoclimatic events associated with the uplift of the central and northern portions of the Andes and the closure of the Isthmus of Panama. We propose routes from south to north in the Neotropics and the use of the Greater and Lesser Antilles as a northward path. Full article

Mosasaurid teeth are abundant in the fossil record and often diagnostic to low taxonomic levels, allowing to document the taxonomic diversity and ecological disparity through time and with fewer biases than in other marine reptiles. The upper Maastrichtian Phosphates of Morocco, with at least fifteen coeval species representing a wide range of sizes and morphologies, undoubtedly represent the richest outcrop in the world for this clade of iconic Mesozoic squamates and one of the richest known marine tetrapod assemblages. Until now, the methods used to link tooth morphology to diets in marine amniotes were mainly qualitative in nature. Here, using the dental morphology of mosasaurids from Morocco, we combine two complementary approaches—a thorough comparative anatomical description and 2D/3D geometric morphometry—to quantitatively categorize the main functions of these teeth during feeding processes and infer diet preferences and niche-partitioning of these apex predators. Our results from combining these two approaches show the following: (1) Mosasaurids from the upper Maastrichtian Phosphates of Morocco occupy the majority of dental guilds ever colonized by Mesozoic marine reptiles. (2) As seen elsewhere in the Maastrichtian, mosasaurines dominate the regional mosasaurid assemblage, exhibiting the greatest taxonomic diversity (two-thirds of the species) and the largest range of morphologies, body sizes (2 m to more than 10 m) and ecological disparities (participating in nearly all predatory ecological guilds); strikingly, mosasaurines did not developed flesh piercers and, conversely, are the only ones to include durophagous species. (3) Halisaurines, though known by species of very different sizes (small versus large) and cranial morphologies (gracile versus robust), maintain a single tooth shape (piercer). (4) Plioplatecarpines were medium-size cutters and piercers, known by very morphologically diverging species. (5) Tylosaurines currently remain scarce, represented by a very large generalist species; they were largely replaced by mosasaurines as apex predators over the course of the Maastrichtian, as observed elsewhere. Also, when comparing tooth shapes with body sizes, the largest taxa (>8 m long) occupied a restricted area of tooth shapes (generalist, durophagous), whereas small and medium-sized species (<8 m long) range across all of them (generalists, durophagous, cutters, piercers). In other words, and probably related to the specificities and advantages of biomechanical resistance, apex predators are never dedicated piercers, micro-predators are conversely never generalists, and meso-predators show the widest range of dental adaptations. These diversities and disparities strongly suggest that Tethyan mosasaurids evolved strong niche-partitioning in the shallow marine environment of the upper Maastrichtian Phosphates of Morocco. Such a high diversity sensu lato just prior to the K/Pg biological crisis suggests that their extinction was rather sudden, though the exact causes of their extinction remain unknown. Finally, Gavialimimus Strong et al., 2020 is systematically reassigned to Gavialimimus ptychodon (Arambourg, 1952), and an emended diagnosis (for teeth and dentition) is proposed for this species. Full article

The development of molecular methods to detect Mytilus hybrids is important for food authentication, conservation, and the sustainable management of shellfish aquaculture as accurate food labeling is a legal requirement, and because introgression may promote undesirable phenotypes or displace native species. However, nuclear and mitochondrial markers can segregate independently, compromising diagnostic congruence between these markers. This study aimed to detect hybrids in the Mytilus edulis species complex using a multi-locus approach, including RFLP-PCR assays for Me 15/16, 16S rRNA, and COIxba, in samples collected from five continents. We used a model-based Bayesian method for hybrid and pure species detection to analyze the diagnostic potential of nuclear and mitochondrial markers in mussel samples from South America, North America, Africa, Oceania, and Europe. Our results showed that the combined use of markers can differentiate between M. trossulus, M. edulis, M. galloprovincialis, and M. chilensis. The combined use of nuclear and mitochondrial molecular markers also improves hybrid detection and allows us to identify introgression using Bayesian analysis. Full article