Set Of Morphological Characters Research Articles

Integrative description of Grevenius annulatus (Eutardigrada, Isohypsibioidea) from North‐West Russia with new data on the species cuticular structure leads to the institution of a new genus

AbstractThe phylogenetic position of the tardigrade species Grevenius annulatus was clarified using specimens from North‐West Russia. Molecular phylogenetic analysis revealed close affinity of this species with the family Isohypsibiidae. At the same time, its isolated position within this clade, supported by a set of unique morphological and biological characters, prompted the distinguishing of a new genus Cucumibius gen. nov. A new genus Chilibius gen. nov. was also established for Isohypsibius sculptus. We provide a detailed description of the ultrastructure of C. annulatus comb. nov. body cuticle. The newly discovered presence of a complex cuticle of the ‘heterotardigrade type’ in the superfamily Isohypsibioidea is discussed.

Plocamiomonas psychrophila gen. et sp. nov. (Pelagophyceae, Heterokontophyta), an Arctic marine nanoflagellate characterized by microscopy, pigments and molecular phylogeny

ABSTRACT During a field campaign in Baffin Bay (June, 1998), a sample dominated by small yellow brown biflagellates was collected from a small pocket of liquid water on the sea ice and established into a unialgal culture. Later it was given strain number CCMP2097 and deposited at the NCMA collection. Growth experiments over a range of temperatures and salinities indicated adaptation to variable Arctic conditions. This strain was studied here using light and transmission electron microscopy, HPLC for characterization of photosynthetic pigments and the relationship to related taxa was elucidated from molecular phylogeny. This integrative approach resulted in suggesting Plocamiomonas psychrophila gen. et sp. nov. the first systematically named Arctic species of the Pelagophyceae. Plocamiomonas had two unequally long flagella and the spherical cells measured 7.5 µm in diameter. Novel morphological characters included (1) a swelling on the mature flagellum, (2) a bi-layered theca, thin elongated arm-like structures emanating from the cell surface and (3) a thin filament above the flagellar transition region. This set of morphological characters represented a novel combination for the Pelagophyceae and together with evidence from the phylogenetic position of Plocamiomonas and eight uncultured cold-water pelagophytes supported the proposal of a new order Plocamiomonadales and a new family Plocamiomonadaceae.

A new enigmatic genus of the ichneumonid subfamily Ctenopelmatinae (Hymenoptera, Ichneumonidae) from Thailand

The Ctenopelmatinae is one of the least explored groups of Ichneumonidae in South East Asia. We describe and illustrate an enigmatic new genus, Thaictenopelma Ranjith, Reshchikov & Quicke with the type species, T. splendida Ranjith, Reshchikov & Quicke, sp. nov., from a moderately high altitude site in northern Thailand. The new genus shows a unique set of morphological characters that distinguishes it from all other ctenopelmatine genera. The presence of a pair of complete latero-median as well as complete dorso-lateral carinae on the T2 are considered autapomorphic characters of the new genus. Affinities of the new genus within the Ctenopelmatinae are discussed and a note on the taxonomic placement is provided.

CONTRIBUTION TO THE GENUS SYMPETRUM NEWMAN, 1833 (ODONATA, ANISOPTERA) FROM SW ROMANIA, WITH A GENERAL DISCUSSION ON SYMPETRUM SPECIES

The paper presents the results of an exploratory research on the genus Sympetrum in two regions in the SW part of Romania (Timiș Plain and Oltenia region), in terms of the faunistic account, species distribution and comparative morphology. The variable, constant and distinctive characters are given for each species. The variability of some taxonomic characters – pterostigma, the male accessory genitalia and the vulvar scale is compared with data from the available literature. The analysis reveals that pterostigma variability and set (combinations) of morphological characters (legs and vulvar scale) go out of the current knowledge, questioning their taxonomic value. A discussion on Sympetrum species is provided from the perspective of the classical principles of systematic zoology: the biological species concept, the reproductive isolation of species, species delimitation, speciation.

Diversification of freshwater crabs on the sky islands in the Hengduan Mountains Region, China

The numerous naturally-fragmented sky islands (SIs) in the Hengduan Mountains Region (HMR) of southwestern China constitute discontinuous landscapes where montane habitats are isolated by dry-hot valleys which have fostered exceptional species diversification and endemicity. However, studies documenting the crucial role of SI on the speciation dynamics of native freshwater organisms are scarce. Here we used a novel set of comprehensive genetic markers (24 nuclear DNA sequences and complete mitogenomes), morphological characters, and biogeographical information to reveal the evolutionary history and speciation mechanisms of a group of small-bodied montane potamids in the genus Tenuipotamon. Our results provide a robustly supported phylogeny, and suggest that the vicariance events of these montane crabs correlate well with the emergence of SIs due to the uplift of the HMR during the Late Oligocene. Furthermore, ancestrally, mountain ridges provided corridors for the dispersal of these montane crabs that led to the colonization of moist montane-specific habitats, aided by past climatic conditions that were the crucial determinants of their evolutionary history. The present results illustrated that the mechanisms isolating SIs are reinforced by the harsh-dry isolating climatic features of dry-hot valleys separating SIs and continue to affect local diversification. This offers insights into the causes of the high biodiversity and endemism shown by the freshwater crabs of the HMR-SIs in southwestern China.

Description of the first-stage juvenile ofAegla jacutingaMarçal & Teixeira in Marçal, Páez, Souza-Shibatta, Sofia & Teixeira, 2020 (Decapoda: Anomura: Aeglidae) from southeastern Brazil

AbstractThe morphologies of only 10 of the 93 described species of Aegla Leach, 1820 are known. We describe and illustrate the external morphology of newly-hatched, first-stage juveniles of Aegla jacutinga Marçal & Teixeira in Marçal, Páez, Souza-Shibatta, Sofia & Teixeira, 2020 using light microscopy and scanning electron microscopy (SEM) comparing them with the same stage in other congeners and providing diagnostic characters. Aegla is morphologically a conservative genus, which creates many problems in the identification of its many cryptic species. It thus becomes necessary to refine the taxonomic characters used in the taxonomy of the group by providing a new sets of morphological characters to be analyzed.

Revisiting the phylogeny of the scolebythid wasps (Hymenoptera: Aculeata) through Bayesian model evaluation and parsimony, with description of a new fossil family of Chrysidoidea

Abstract Scolebythidae constitute the smallest family of Aculeata in number of extant species, but with a considerable diversity of extinct lineages. Twenty Cretaceous species are attributed to the family coming from deposits in Canada, Lebanon, Myanmar, New Jersey, and Spain. However, several of these taxa lack characters of the family groundplan. Although phylogenetic investigations have been conducted for the family based on a relatively small set of morphological characters, the substantial diversity of species from Burmese amber have not yet been accounted for in a phylogenetic perspective. In the present work, we reconstruct the phylogenetic relationships of Scolebythidae using a new morphological matrix and explore it through parsimony and Bayesian model evaluation. In Bayesian analyses, homoplasy-based partitioning outperformed anatomy-based partitioning and the unpartitioned models. Our phylogenetic results support the relocation of a few taxa previously attributed to Scolebythidae to the families Bethylidae and Chrysididae. We also describe †Chrysopsenellidae fam. nov., a new family of Chrysidoidea, based on an inclusion in Burmese amber. In all analyses the new family is recovered as closely related to Scolebythidae, with the whole clade being sister-group to Chrysididae + †Chrysobythidae. Finally, we discuss the origin of the Burmese amber biota distinctiveness.

The conspecificity of Aulacoseira konstantinovii and Praecyclostephanos boengchhmariensis with comments on the genus Praecyclostephanos

The centric diatom species Aulacoseira konstantinovii was described from Lake Tonlé Sap (Cambodia) but was erroneously assigned to the genus Aulacoseira. Subsequently, based on a unique set of morphological characters, the genus Praecyclostephanos with the single species P. boengchmariensis was established based on the material from this lake. Examination of published data has allowed us to compare the morphology of A. konstantinovii and P. boengchmariensis and confirm their conspecificity. A new combination, Praecyclostephanos konstantinovii comb. nov., is therefore proposed.

Pollen Morphology of Convolvulaceae from Southeastern Amazonian Cangas and Its Relevance for Interaction Networks and Paleoenvironmental Studies.

Serra dos Carajás harbors a unique open plant community in Amazonia, known as canga vegetation, with several endemic species coexisting with the potential threat of large-scale iron ore mining. In this sense, Convolvulaceae occur in a wide variety of canga geoenvironments with multiple flower visitors, but the scarcity of data on its pollen morphology prevents the correct association between Convolvulaceae species with floral visitors, as well as the precise identification of their habitats throughout the Quaternary. Therefore, this study aims to contribute to the taxonomic knowledge and refinement of the identification of insect-plant networks of endangered plants, including Ipomoea cavalcantei. Pollen grains were examined by light and scanning electron microscopy (LM and SEM, respectively), and the morphological parameters obtained were statistically analyzed using principal component analysis. Therefore, all species were differentiated based on aperture types and exine ornamentation. The set of morphological characters indicated that echinae morphology, easily identified under LM, was effective for the identification of Ipomoea species. This work represents the first robust pollen database for a precise identification at the species level of Convolvulaceae from southeastern Amazonian cangas.

Systematic position of the genus Metacanthocephalus Yamaguti, 1959 (Palaeacanthocephala: Echinorhynchida) inferred from molecular evidence, with a redescription of Metacanthocephalus ovicephalus (Zhukov, 1960).

The familial affiliation of the echinorhynchid palaeacanthocephalan genus Metacanthocephalus has been uncertain, with the three families Echinorhynchidae, Leptorhynchoididae, and Rhadinorhynchidae having been suggested as its parent taxon. In this study, adult individuals of Metacanthocephalus ovicephalus from the intestine of the cresthead flounder Pseudopleuronectes schrenki (new host) and the dark flounder Pseudopleuronectes obscurus in Hokkaido, Japan, were examined. Using three gene markers (mitochondrial cytochrome c oxidase subunit I; nuclear 18S and 28S rRNA genes) determined from two specimens of M. ovicephalus, a molecular phylogenetic analysis was performed along with relevant sequences available in public databases representing 26 species in eight families of the order Echinorhynchida, along with five species from Polymorphida and two from Eoacanthocephala. The resulting phylogram showed that M. ovicephalus was nested within a clade along with nine species in eight genera (Brentisentis yangtzensis, Dentitruncus truttae, Dollfusentis bravoae, Koronacantha mexicana, K. pectinaria, Leptorhynchoides thecatus, Neotegorhynchus cyprini, Pseudoleptorhynchoides lamothei, and Tegorhynchus [= Illiosentis] sp.). In this paper, we propose i) a set of morphological characters to circumscribe members represented by this clade as a Linnaean higher taxon, ii) to place this taxon at the rank of family, iii) to refer to it as Leptorhynchoididae, and iv) to regard Illiosentidae as a junior synonym of Leptorhynchoididae. Our morphological examination revealed a single vaginal sphincter in M. ovicephalus, a character that was not mentioned in any of the previous literature. By this character, along with geographical distribution and host fish, six congeners currently recognized in Metacanthocephalus can be divided into two groups.

No longer in doubt: Discovery of a second specimen corroborates the validity of Anolis incredulus Garrido and Moreno 1998 (Reptilia, Iguania).

The species Anolis incredulus was proposed based on a single, poorly preserved specimen from the Sierra Maestra (mountain range) of southeastern Cuba. As its name suggests, this species was considered likely to raise doubts when it was first proposed, and it has been explicitly treated by some recent authors as a species inquirenda (a species of doubtful identity). Here we report on a second specimen of Anolis incredulus discovered in the amphibian and reptile collection of the National Museum of Natural History (Smithsonian Institution) that was collected more than 100 years before the holotype. We describe this specimen in detail and compare it both with the description of the holotype of A. incredulus and with presumed closely related Cuban species, providing evidence that it matches closely with the former and is distinct from the latter, thus corroborating the status of A. incredulus as a valid species. We also score and measure the specimen for sets of morphological characters to make inferences about its phylogenetic relationships and ecology (structural habitat use). Our results indicate that Anolis incredulus is likely a member of a clade of mostly Cuban twig-anole species and that it is a member of the twig ecomorph category, although its reported green coloration suggests either an erroneous ecomorph assignment or a difference in color from that of most other species of Cuban twig anoles.

Eriocaulaceae: A new classification system based on morphological evolution and molecular evidence

AbstractPaepalanthus, in its current sense, is the most diverse genus of Eriocaulaceae in the Neotropics, comprising about 400 species. Previous studies have consistently found that the genus is not monophyletic, also being morphologically heterogeneous and diagnosable by a set of homoplasies; thus, the current circumscription needs to be revised. The new classification proposed here uses a comprehensive phylogeny of Paepalanthus and closely related genera as a framework and an evaluation of a set of morphological characters using ancestral state reconstruction, which allowed the recognition of strongly supported clades with morphological diagnosability. We propose the recognition of 12 genera in the clade encompassing Paepalanthus and allied groups, including six new genera (Coracoralina, Floralia, Giuliettia, Gnomus, Hydriade, Nisius), two new statuses (Cryptanthella, Monosperma), the reestablishment of Actinocephalus, Lachnocaulon, and Tonina, and a recircumscription of Paepalanthus. In this new circumscription, Paepalanthus comprises 257 species, most of them restricted to the Brazilian campos rupestres. Among the proposed genera, nine have potential morphological synapomorphies, one has a restricted geographical distribution, and the other two can be recognized by a combination of characters. Newly generated seed morphology data is consistent within the different genera and plays an important role in their recognition. A total of 136 new combinations are hereby proposed. We provide a genus‐level identification key, as well as generic descriptions, diagnostic features, photos illustrating their morphological diversity, maps and notes on distribution, and lists of species by genus.

On the differentiation and distribution of the rare New Zealand endemic Rehubryum bellii (Malta) F.Lara, Garilleti & Draper (Orthotrichaceae, Bryophyta)

ABSTRACT Introduction A recently published study revealed an unnoticed New Zealand endemic and monotypic genus, which was named Rehubryum. It was based on Ulota bellii, a species described by Nikolajs Malta for which only two previous collections were known. Despite this sample size limitation, Malta simultaneously published two varieties, each based on one of the two specimens: the type variety and U. bellii var. longicolla. Methods Specimens from 80 localities between 0 and 1430 m a.s.l. from both the North and South Islands of New Zealand were studied. Type material of both varieties of Ulota bellii was included in the study, and the ecological affinities of Rehubryum bellii were analysed. Key results and conclusions Morphometric analysis supports the conclusion that our recent collections correspond to the original concept of Ulota bellii, now combined as Rehubryum bellii. Additionally, var. longicolla is synonymised with the type variety based on a lack of morphological differences. Rehubryum bellii is described in detail and illustrated, and its distribution and ecological affinities are discussed. Rehubryum bellii presents a set of morphological diagnostic characters: leaves with a submarginal band of elongate cells, papillose-denticulate margins in the base–lamina transition, and an endostome with 16 segments. Similarities and differences between Rehubryum and Atlantichella, the sister genus from the northern hemisphere, as well as the distinction from Australasian species of Orthotrichaceae, are discussed. The genus is now known from 12 localities in montane areas of the South Island of New Zealand and two isolated mountains on the North Island.

Italobdella bieleckii sp. n. (Hirudinea: Piscicolidae), a new leech species from the Danube in Slovakia

Notwithstanding the genus Italobdella has been hypothesized to have doubtful taxonomic value, we decided to update its diagnosis by describing the new species – Italobdella bieleckii sp. n. The leeches were collected from the stony bottom along the shore of the Danube River in Slovakia. In the study, we implemented the model of leech body form and the set of external and internal morphological characters to present the similarity of the new species to the other fish leeches. As a result, we were able to construct the key for determining leeches belonging to the genus Italobdella hoping that the species could be found and determined by other researchers. This would enrich our knowledge about the actual distribution of these leeches and strengthen their systematic position in the genus.

Entomoneis grisslehamnensis, a New Diatom (Bacillariophyceae) from the Baltic Coast of Sweden with taxonomic and ecological notes on Entomoneis paludosa (W. Smith) Reimer

The diatom genus Entomoneis includes species with panduriform frustules characterized by a bilobate, elevated keel, sigmoid raphe canal and numerous open, porous girdle bands. During a phytoplankton survey along the Baltic coast of Sweden, we observed numerous Entomoneis cells, some belonging to the well-known Entomoneis paludosa, while others remained unknown. Morphological and ultrastructural studies of the unknown species were performed with light microscopy (LM), scanning (SEM) and transmission (TEM) electron microscopy, and revealed a unique set of morphological characters. Live cells of Entomoneis grisslehamnensis sp. nov. contain one plate-like plastid and show various degrees of torsion about the apical axis. Microscopic features of cleaned frustules are discussed in comparison with similar species. Most importantly, every 2nd to 5th virga is strongly elevated, uniseriate striae are composed of quadrangular areolae with finely perforated hymenes; the winged keel with a discernible raphe canal is structurally strengthened by raphe fibulae with a flattened wing area, and the main part of the valve bulges towards the margins; striation is decussate on the wings and there is one row of raphe canal areolae at the central area. In addition to describing this new species of an underappreciated, yet cosmopolitan diatom genus, we contribute to the taxonomy of E. paludosa with LM, SEM and TEM details, some of which were not sufficiently noted in original descriptions or re-examination of type material and other specimens made by Dalu et al. [2015. A re-examination of the type material of Entomoneis paludosa (W. Smith) Reimer and its morphology and distribution in African waters. Fottea 15: 11–25] and Long et al. [2022. Ultrastructure of three species of Entomoneis (Bacillariophyta) from Lake Qinghai of China, with reference to the external areola occlusions. PhytoKeys 189: 29–50. doi:10.3897/phytokeys.189.78149].

Description of Uniphylus gen. nov., a new genus of Carcharodini (Lepidoptera, Hesperiidae, Pyrginae) for Staphylus evemerus Godman & Salvin, 1896.

Staphylus evemerus Godman & Salvin, 1896 is a species with a unique set of morphological characters within Carcharodini. Also, mitochondrial cytochrome oxidase subunit 1 (COI) sequences analysis demonstrated a large genetic distance with other related genera of the tribe. Therefore, this paper aims to describe a new genus for this species, which is named as Uniphylus gen. nov. Besides the morphological redescription of the male of Uniphylus evemerus (Godman & Salvin, 1896) new comb., the description of the female is provided for the first time, as well as an updated distributional map with all records known so far for this species.

A just overtime discovery: another new species of Echinosepala (Orchidaceae) from Costa Rica

Echinosepala truncata is described as new to science and illustrated from the holotype. It is compared with E. tomentosa, from which it differs by the sparsely lanate ovary, the narrowly obovate, apically rounded synsepal, the spathulate, apically and basally rounded petals, and the rectangular, apically truncate lip. The phylogenetic relationships of the new species could be hypothesized based on a shared set of morphological characters and geographic distribution.

Coronamoeba villafranca gen. nov. sp. nov. (Amoebozoa, Dermamoebida) challenges the correlation of morphology and phylogeny in Amoebozoa

Coronamoeba villafranca gen. nov. sp. nov. is a small amoeba isolated from the surface planktonic biotope in the Bay of Villefranche (Mediterranean Sea). It has a confusing set of morphological and molecular characters. Its locomotive form is subcylindrical and monopodial with monoaxial cytoplasmic flow and occasional hyaline bulging at the anterior edge (a monotactic morphotype). Based on this set of characters, this amoeba is most similar to members of the genus Nolandella (Tubulinea, Euamoebida). However, molecular phylogenetic analysis based on only the small subunit ribosomal RNA (SSU rRNA) gene and on two concatenated markers (SSU rRNA gene and actin) robustly places this species in the Discosea, specifically, in a clade with Dermamoeba and Paradermamoeba (Dermamoebida) as the closest described relatives, and several SSU rRNA clones from environmental DNA. A unique glycocalyx of the studied amoeba consisting of complex separate units with pentameric symmetry may be considered a unifying character of this species with other dermamoebids. The monotactic morphotype demonstrated by these amoebae primarily occurs in Tubulinea but was recently confirmed in other clades of Amoebozoa (e.g. Dactylopodida and Variosea). This morphotype may be the plesiomorphic mode of cell organization in Amoebozoa that might have evolved in the last amoebozoan common ancestor (LACA) and conserved in several lineages of this group. It may reflect basic characteristics of the cytoskeletal structure and functions in Amoebozoa.

Automated identification of diverse Neotropical pollen samples using convolutional neural networks

Abstract Pollen is used to investigate a diverse range of ecological problems, from identifying plant–pollinator relationships to tracking flowering phenology. Pollen types are identified according to a set of distinctive morphological characters which are understood to capture taxonomic differences and phylogenetic relationships among taxa. However, categorizing morphological variation among hyperdiverse pollen samples represents a challenge even for an expert analyst. We present an automated workflow for pollen analysis, from the automated scanning of pollen sample slides to the automated detection and identification of pollen taxa using convolutional neural networks (CNNs). We analysed aerial pollen samples from lowland Panama and used a microscope slide scanner to capture three‐dimensional representations of 150 sample slides. These pollen sample images were annotated by an expert using a virtual microscope. Metadata were digitally recorded for ~100 pollen grains per slide, including location, identification and the analyst's confidence of the given identification. We used these annotated images to train and test our detection and classification CNN models. Our approach is two‐part. We first compared three methods for training CNN models to detect pollen grains on a palynological slide. We next investigated approaches to training CNN models for pollen identification. Because the diversity of pollen taxa in environmental and palaeontological samples follows a long‐tailed distribution, we experimented with methods for addressing imbalanced representation using our most abundant 46 taxa. We found that properly weighting pollen taxa in our training objective functions yielded improved accuracy for individual taxa. Our average accuracy for the 46‐way classification problem was 82.3%. We achieved 89.5% accuracy for our 25 most abundant taxa. Pollen represents a challenging visual classification problem that can serve as a model for other areas of biology that rely on visual identification. Our results add to the body of research demonstrating the potential for a fully automated pollen classification system for environmental and palaeontological samples. Slide imaging, pollen detection and specimen identification can be automated to produce a streamlined workflow.

Two new species of Hemidactylus Goldfuss, 1820 (Squamata: Gekkonidae) from the rocky outcrops of the Deccan plateau, peninsular India

The gekkonid diversity of the under-explored dry zones in Peninsular India is not yet completely inventoried, as evidenced by frequent new species descriptions. Here, we describe two new species of Hemidactylus from the dry rocky zones of Deccan Plateau viz. Hemidactylus mahonyi sp. nov. from Sandur Hills and Hemidactylus srikanthani sp. nov. from Devarayana Durga Hills, Karnataka State of Peninsular India. The new species belong to the morphologically cryptic H. murrayi Clade but differ from each other and the known congeners by a set of morphological characters and possess non-overlapping distribution ranges. Furthermore, the new species are also divergent (> 6.4% uncorrected p-distance) from their nearest related congeners, and from one another with respect to the ND2 mitochondrial gene. Recently, other new species of reptiles have been described from the two aforesaid type localities, indicating that further bio-inventories in the dry zones of peninsular India will yield more such novelties.