Examination of the description and illustrations of Rhabdocheirus incertus Bonnier, 1898, shows that this taxon, originally described as an epicaridean isopod, is the pantochelis larval stage of a hyperiid amphipod belonging to the genus Vibilia H. Milne Edwards, 1830. Evidence is provided to support the synonymy of R. incertus with V. armata Bovallius, 1887 and Rhabdochiridae Richardson, 1905 with Vibiliidae Dana, 1852.

Considerable confusion has surrounded the identity of the nominal species, Paraplagusia dollfusi Chabanaud, 1931, known only from two specimens: the holotype, collected in Gulf of Suez, Red Sea, and a second, non-type specimen (reported with the trinomial Cynoglossus (Trulla) dollfusi) captured in the Suez Canal, Red Sea. No catalogue number, illustration or photograph of the type specimen accompanied the original description, which also lacked critical information to confidently assign this species to a genus or to diagnose it from previously described tongue soles possessing similar attributes. Both the type and non-type specimen have been reported as lost for over 40 yr, further confounding attempts to resolve questions regarding the identity and status of this nominal species. During its history, C. dollfusi has been considered as a junior subjective synonym of C. sealarki Regan, 1908, a senior subjective synonym of C. cleopatridis Chabanaud, 1949, and has been misidentified as C. zanzibarensis Norman, 1939. The trinomial, Cynoglossus (Trulla) dollfusi, has also been considered as a second nominal species. Recently, specimens currently curated in the same jar in the fish collection of the Muséum National d'Histoire Naturelle (Paris) and identified as C. zanzibarensis collected in the Red Sea were determined to be the missing holotype of P. dollfusi Chabanaud, 1931 and the second-known specimen of C. dollfusi. Their sizes, as well as their meristic and morphometric features, agree with those provided in the original description of the holotype of C. dollfusi and for those in the account of the second specimen. Rediscovery of the holotype confirms the validity of this species. Based on the holotype and non-type specimen and information from the literature, C. dollfusi is redescribed and diagnosed from other Indo-West Pacific species of the genus. Information from these two specimens also provides the necessary data to resolve historical problems regarding the identity and taxonomic placement of this species. Additionally, this new information resolves Red Sea distributional records for three other species of Cynoglossus. Conclusions from the present study indicate: a) Chabanaud erred in placing his nominal species dollfusi in the genus Paraplagusia. New data allow confident assignment of this species to Cynoglossus. b) The hypothesis that two nominal species are represented by the names P. dollfusi and Cynoglossus (Trulla) dollfusi is unsupported. Cynoglossus (Trulla) dollfusi is a new combination reflecting transfer of dollfusi from Paraplagusia to Cynoglossus. c) The hypothesis that C. dollfusi (Chabanaud, 1931) is a junior subjective synonym of C. sealarki is not supported by the data. These two species differ significantly to warrant recognizing both as valid. d) C. dollfusi has erroneously been considered the senior synonym of C. cleopatridis Chabanaud, 1949, a nominal species known only from a damaged holotype also collected in the Red Sea. Cynoglossus dollfusi was redescribed in a global revision of the genus based mostly on information from the holotype of C. cleopatridis, a decision that significantly changed the species concept of C. dollfusi from that intended in the original description. e) The hypothesis that C. cleopatridis Chabanaud, 1949 is a junior subjective synonym of <

Two new species of Mesocletodes were identified and described from the samples collected for an ecological study of benthic meiofauna in the bathyal zone of San Diego Trough (Southern California Continental Borderland, Pacific margin). Mesocletodes tetrasetosus appears to be closely related to M. langi and M. ameliae by sharing five setae in the endopod of mandibular palp. However, M. tetrasetosus differs from both congeners in the following features: (1) the second segment of antenna with seven setae, (2) the exopod of mandibular palp with two setae, (3) the terminal margin of praecoxal arthrite of maxilla with eight elements, (4) the basis of maxilla with a total of six setae, (5) the syncoxa of maxilliped with a strong or robust bipinnate seta, (6) the P1 enp-1 with an inner seta, (7) the P1 enp-2 innermost distal seta and distal spine are translocated, (6) the P3–P4 endopod with total of 4:3 elements, (7) the P5 endopod outermost seta three times as long as in M. ameliae, (8) the P5 endopod medial and innermost setae are sub equal, and (9) the caudal rami is as long as the last two urosomites. Mesocletodes nudus is closely related to M. fladensis by the presence of an outer spine along the midlength of P1 exp-1, and the P1 exp-3 distal outer element is almost as long as the exopod. However, M. nudus can be distinguished by the following character states: (1) the A1 with six segments, (2) the P4 enp-2 both distal setae are equal in length, (3) the P4 exp-3 outer spines are almost 0.5 times longer than in M. fladensis, (4) the P5 exopod with a total of three elements, (5) the P5 endopod inner distal seta is relatively slender and flexible, (6) the P5 exopod is reduced to half in its length and width, and (7) the P5 baseoendopod is represented by a transversely elongated plate, rectangular in shape. In addition, a key to the species of Mesocletodes including both new species is provided.

A new species of harpacticoid copepod, Halectinosoma foveolata, was described from sandy sediments on several intertidal areas of Korea. This new species is mostly similar to H. dimorphum Coull, 1970, but differs from the latter by the following characteristics combined: (1) the third segment of antennule is longest; (2) the first exopodal segment of antenna has a row of spinules; (3) the mandibular gnathobase is composed of chitinous teeth without dorsal seta; (4) the female P5 has an incomplete boundary between the exopod and the baseoendopod; (5) the female P5 baseoendopod has two rows of spinules. We also discuss the state of H. arenicola sensu Itô (1973), reported from the Japanese coast, which is considered here a synonym with the new species.

The female of Heteromysoides simplex Hanamura & Kase, 2001 is described for the first time based on material collected from a submarine cave on Ie-jima Island, Ryukyu Islands, southwestern Japan. Morphological descriptions and illustrations of this specimen are given.

The Ilin cloud rat Crateromys paulus, identified from a single individual in 1981 and collected from an undocumented location in Ilin Island, Mindoro, Philippines, is now considered to be “data deficient” and possibly extinct. 96 murid dental fossil remains were recently recovered within a two-meter excavation of well stratified and chronometrically dated deposits at the archaeological sites of Bubog I and Bubog II on Ilin Island. Research on these well-preserved murid rodent remains confirms the past presence of C. paulus on Ilin Island and describes for the first time variability in dental morphology of this species. The succession of fossils within the detailed stratigraphic sequence also provides us with information on C. paulus throughout the Holocene and on its possible recent extinction.

One hundred seventy-four water bear specimens and 16 eggs (Phylum Tardigrada) were collected from mosses and lichens in South Carolina, representing eight genera and 12 species. Some species could only be identified to species group. Nine species or species groups were new records for South Carolina and two were new for the United States. Echiniscus danieli sp. nov. is described from moss and lichen collected from trees on the campus of the University of South Carolina, Columbia, South Carolina, southeastern U.S.A. The species belongs to the Echiniscus bigranulatus group; its dorsal plate cuticle structure consists of true pores, pillars, and granulation. It differs from other species in the group in lacking basal spurs on any of its claws and in the weak development of dentate collars on the fourth legs (i.e., dentate collar absent, or present with few or no teeth). The bigranulatus group has been considered Neotropical and Antarctic in distribution. The presence of Echiniscus danieli sp. nov. in Nearctic North America therefore expands its confirmed geographical range.

The generic name Polyborus has been traditionally associated with the “Crested Caracaras”, but confusion over its correct application has led to it recent falling out of use. Polyborus is based on a description by Marcgrave accompanied by a poor illustration, but only 2 species have ever been seriously considered as the identity of this description Long-winged Harrier Circus buffoni and Southern Caracara Caracara plancus. The nomenclatural history of this name is discussed and the identity of Marcgrave's description is elucidated as Yellow-headed Caracara Milvago chimachima. The implications for nomenclature are discussed, and it is recommended that both Polyborus and the name Falco brasiliensis (also based on the same description) be suppressed.

A new species of Thaumastoderma (Gastrotricha: Macrodasyida: Thaumastodermatidae) is described from sublittoral sediments on the islands of Tobago (Trinidad and Tobago) and Carrie Bow Cay (Belize). Thaumastoderma ponticulus sp. nov. is similar to Th. ramuliferum and Th. cantacuzeni based on the presence of four pairs of dorsal cirrata tubes and a compound pair of spatulate tentacles. The main distinguishing characteristic is the presence of a fleshy bridge that interconnects the anterior and posterior spatulate tentacles on the head. Additional characters include the presence of two rows of anterior adhesive tubes, seven pairs of ventrolateral adhesive tubes, and five pairs of posterior adhesive tubes.

A new species of Redudasys (Macrodasyida: Redudasyidae) is described from Texas and Oregon, U.S.A. A single Texas specimen was reported (but not formally described and named) in 2014 from an artesian outflow in Spring Lake, San Marcos, Texas. The Texas specimen provided the first record of Redudasys from outside Brazil. Fifteen specimens were found and studied in 2015 and 2016 from sand pockets among boulders in the Little Nestucca River, near Pacific City, Oregon. Redudasys neotemperatus n. sp. is morphologically and genetically distinguishable from Redudasys fornerise Kisielewski, 1987a, the only formally described species in the genus up until now, and morphologically distinguishable from “Redudasys sp.”, an unnamed form reported by Garraffoni et al. in 2010 without genetic information. The Texas and Oregon specimens agree well morphologically and genetically.

This study is part of a larger research program aimed at shedding light on meiofauna and macrofauna communities of the subtropical Eastern Province of KwaZulu-Natal, South Africa. Previous articles on the phylum Gastrotricha have detailed faunistic and preliminary taxonomic data on marine and freshwater species found in the iSimangaliso Wetland Park. Here, two new interesting marine macrodasyidan species, in the families Cephalodasyidae and Turbanellidae, are reported from a wider area of the KZN coast. Descriptions are based on observations carried out on living specimens using differential interference contrast microscopy. Pleurodasys incomptus new species is the second species in the genus; surprisingly, it lacks the peculiar gravireceptor organs (pharyngeal knobs) thought to be an autapomorphic trait of the genus. Paraturbanella africana new species is a mid-sized species (up to 520 μm in length), showing a peribuccal swelling; its most obvious autapomorphic trait pertains to the testes, which are located well passed half the body rather than at- or near the pharyngo-intestinal junction as occur in the other species of the genus. The relevant anatomical novelties shown by the two new species testify that current knowledge about gastrotrich basic morphology is far from complete. This holds true also for taxa that are considered to be well-known (e.g. the speciose genus Paraturbanella), and stresses once again the importance of investigating new geographic areas in order to improve our understanding of global gastrotrich morphological diversity and species richness.

Surveys of marine gastrotrichs on the coast of South Korea yielded a new species of the genus Tetranchyroderma, bearing 5-pronged hooks as a cuticular armature. Tetranchyroderma hummoni is characterized by a dorsal armature adorned with pentancres, whose central tines are about twice as long as peripheral tines. The new species is also characterized by bearing 3 large and broad papillae per side along boundary row of pentancres on oral hood, a pair of rod-like cephalic tentacles, and a pair of modified pestle organs. Moreover, this new species is clearly distinguished from its congeners by the number of dorsal, dorsolateral and ventrolateral cirratum-type tubes (6−10, 13−19, and 9−14 per side, respectively), and by a pair of foot-like ventral adhesive tubes. The description of the new species belonging to the genus Tetranchyroderma is based on detailed illustrations and scanning electron microscopy. We also provide a short account on the variability within the species, including the morphological difference between juveniles and adults.

Molecular surveys and studies of the muscle anatomy made evident that the mesopsammic gastrotrich Xenotrichula intermedia, previously regarded as a cosmopolitan species, comprises several distinct taxonomic units. These entities are to date referred to as cryptic species. Although other morphological traits seemed insufficient to differentiate geographically distant populations, investigations of the myomorphology displayed significant differences. Three muscular morphotypes of X. intermedia are known and distinguishable via properties of their dorsoventral and circular musculature. However, previous studies using confocal laser scanning microscopy (CLSM) conducted observations of the muscle architecture that aimed to apply older terminology of the only existing reconstruction that was based on fluorescence microscopy. Since detailed 3D reconstructions of the myoanatomy were never performed, comparisons between different morphotypes of X. intermedia stay a difficult endeavor. In this study, the muscular system of a North Sea population of X. intermedia is investigated and reconstructed using CLSM and 3D reconstruction software. Our aim is to test whether this population, adjacent to the type locality of X. intermedia, constitutes another muscular morphotype. The overall musculature of the North-Sea population is similar to that of the Mediterranean specimens. A Baltic Sea individual appears myoanatomically identical to these populations, too. This indicates a distinct morphotype with a pan-European distribution. Since the known muscular morphotypes are clearly distinguishable, we propose the presence of a species complex comprising a pan-European X. intermedia, a Persian X. aff. intermedia and a NW Atlantic X. aff. intermedia. Furthermore, our investigation demonstrates a much higher complexity of the longitudinal musculature than previously assumed, which leads us to reinterpret earlier myomorphological data, amend some terminology, and reconsider statements of homology that will provide a feasible foundation for future comparative studies.

The spermatozoon of an undescribed species of Dolichodasys (Cephalodasyidae) from the Pacific coast of Panama was studied at structural and ultrastructural levels. Under optical microscopy, it appears as a short and wide cell with pointed extremities but without a flagellum. The cell body is made up of two well distinct regions: an anterior region with a homogeneous appearance, and a posterior region containing an evident rod-like nucleus. Under TEM, a peripheral layer of microtubules densely arranged extends for the whole cell length. In the anterior cell region, microtubules surround many tubular cisternae of smooth endoplasmic reticulum (SER), and a thin layer of vesicles with a probable acrosomal function lies just beneath the plasma membrane. The rod-shaped nucleus fills up the posterior cell region and forms a pouch that hosts a single large, irregular mitochondrial mass. A hypothesis about the motility of this aflagellate cell is advanced, on the basis of the coexistence of singlet microtubules and SER. The general architecture of Dolichodasys sp. spermatozoon departs from the Macrodasyida sperm basic model, consisting of a filiform cell with a corkscrew-shaped acrosome, a spring-shaped nucleus surrounding a mitochondrial axis and an ordinary flagellum. The unusual morphology of the Dolichodasys sperm seems to be unique in the family Cephalodasyidae: the data available for 6 species belonging to the other 4 genera of the family report spermatozoa perfectly matching the basic sperm plan of the Macrodasyida. A sister-taxon relationship between Dolichodasys and Cephalodasys, two genera drastically different in sperm shape, emerged from recent phylogenetic molecular studies, but it needs confirmation due to the still limited number of molecular data and the likely polyphyletic nature of the family Cephalodasyidae.

Geographical patterns in microorganisms' distribution is a matter of intense debate. Following the assumption that “everything is everywhere” (EiE hypothesis), it is expected that microscopic animals do not have any scale spatial pattern of distribution due to high abundances, resting stages, and long-distance dispersal. Gastrotrichs are one of the most common components of the marine soft-body meiofauna. To assess the validity of EiE hypotheses on marine gastrotrichs, we applied Parsimony Analysis of Endemism (PAE) to identify areas of endemism. We used provinces of coastal and continental shelves of the world as operational units to define the distribution of 458 marine species of Gastrotricha. We found 10 areas of endemism, most of them were recorded from Europe and North America, and some areas were also consistent with the distribution of other benthic groups. An area of endemism is obtained when at least two species are perfectly congruent in their distribution. Moreover, the state of knowledge of the true species distribution is directly related to the intensity and spatial variation of the sampling effort. Thus, it is not a surprise to note that most areas of endemism are in the North Hemisphere, where gastrotrichs have been especially and longer sampled and their geographic range size is well known. On the other hand, the absence of endemism areas in South Hemisphere is related to sampling insufficiency. However, some level of endemism was found and the ubiquitous distribution of gastrotrich species is strongly questioned.

The aim of the study was to evaluate the changes in abundance, species richness, and diversity of epiphytic Gastrotricha in the littoral of a mesotrophic lake. The influence of pH and oxygen on their occurrence was also investigated. Gastrotricha occurred throughout the year: 27 species were identified together, and species richness varied at different seasons. The highest number of species on water vegetation was found in the summer (26 species), while in the winter season only 7 species were present. Species diversity expressed by the Shannon index, in spring, summer, and autumn was high and amounted 2.10, 2.37, and 2.31, respectively. In winter, the value of the index was significantly lower and amounted 0.59. Three species were found to be dominant from spring to autumn with the dominance over 9.0%: Heterolepidoderma macrops Kisielewski, 1981, H. ocellatum (Mečnikow, 1865), and Lepidodermella squamata (Dujardin, 1841). The GLM analysis revealed that number of collected species in spring, summer, and autumn does not depend either on season or on pH and oxygen content. The lowest density of gastrotrichs was found in winter (average of 33 10⁻³ indiv. m⁻²), whereas the highest was found in summer (average of 1392 10⁻³ indiv. m⁻²). The density differed with season and neither pH nor oxygen content had an effect upon gastrotrich densities.

The genus Pseudostomella is comprosed of 17 species distributed in distinct coastal and shelf areas of the world. This taxon is characterized by a fleshy preoral apparatus, which is unique to the family and easily distinguishes species of Pseudostomella from species of the other 7 genera. The present study has two aims: 1) provide a phylogenetic reconstruction based on morphological characters using all valid species of the genus Pseudostomella; and 2) perform a Brooks Parsimony Analysis (BPA) based on new and published phylogenetic analyses to determine the biogeographical history of the thaumastodermatid lineage. The cladistic analysis conducted here supports the monophyly of Pseudostomella and the internal branchs are also supported by a relative high number of well-defined synapomorphies. Regarding historical biogeography, our results suggest that the thaumastodermatid diversification first occurred in epicontinental seas from the southern margin of Gondwana. These findings for thaumastodermatid gastrotrichs are similar to those of other historical biogeographical studies on marine invertebrates.

Sexual dimorphism patterns in wing area, wing loading, and wing aspect ratio of Black Vulture (Coragyps atratus) and Turkey Vulture (Cathartes aura) are unknown but are of particular interest given the prevalence of these species in scavenging communities in the Western Hemisphere. I assessed these variables in sexed specimens from wintering populations in Nashville, Tennessee. Black Vultures exhibited higher wing loading and a lower wing aspect ratio than Turkey Vultures. Neither species exhibited significant age-related or sexual dimorphism in body weight, wing span, wing area, wing loading, or wing aspect ratio. The relatively low variance observed in the pooled sample of immatures (∼9–21 mo old) and adults suggests that definitive wing size and shape are acquired several years before individuals develop the bare rugose skin and head caruncles characteristic of adults. In a broader context, this study tentatively suggests that variance estimates for wing morphology obtained from unsexed vulture populations may not be unduly inflated by undetected sexual or age-related dimorphism.

The mesoparasitic copepod Cardiodectes bellottii is described from specimens recovered from the myctophid fish, Benthosema glaciale in the Mediterranean Sea. Another parasitic copepod, found on the same host species, Cardiodectes meduseaus, exhibits identical external morphology, is conspecific with C. bellottii and is considered as a junior synonym.