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Several adult female monstrilloid copepods, collected in March 2022 from the protected reef area of Xcalak, on the southern part of the Mexican Caribbean coast, proved to belong to two undescribed species of Monstrilla Dana, 1849. They are described here as M. xcalakensis sp. nov. and M. annulata sp. nov., partly by use of scanning electron microscopy. Females of the two species are generally similar but differ in: (1) antennular segmental structure, (2) antennular armature and ornamentation, (3) structure and setation of the fifth leg, (4) number and modifications of the caudal setae, and (5) integumental ornamentation. Comparison with congeneric species revealed distinctive features for both species that support their status as new. These two species are interesting additions to the reef-dwelling monstrilloid copepod fauna of the Mexican Caribbean and confirm Monstrilla as the most diverse genus of monstrilloids in this area, now represented by nine species.
The enigmatic ‘y-larvae’ (Thecostraca: Facetotecta) are microscopic marine planktonic crustaceans that were discovered more than a century ago, yet to this day their adults remain unknown. Despite occurring locally in large diversities, and therefore presumably being of ecological importance, only 17 species have been described globally, rendering it practically impossible to identify any y-larval specimen from any locality. The fact that species have been based on different life stages (nauplii and/or cyprids) further hampers identification. Y-larvae include many forms with planktotrophic (feeding) nauplii and even more with lecithotrophic (non-feeding) nauplii. At one coral-reef locality on the shore of Sesoko Island (Okinawa, Japan), extensive fieldwork in 2018 and 2019 confirmed an enormous taxonomic diversity of y-larvae there. Here, we present morphological diagnoses and an identification key for 34 lecithotrophic y-naupliar types (or morphospecies), which will correspond minimally to the same number of species when described. As a temporary measure, all are referred to by alphabetical parataxonomic designations, except for three that have been formally described already within the genus Hansenocaris Itô, 1985. To this should be added an additional 7–9 planktotrophic y-naupliar morphospecies, which are only treated briefly. Most often, y-larval taxonomy has been based on the cyprid stage, but the large morphological diversity of y-nauplii suggests that nauplii are at least as important for taxonomy. Lecithotrophic y-nauplii display a multitude of body shapes, the form-evolution of which is discussed here with reference to a recent molecular phylogeny of Facetotecta partly based on material from the same site. An indirect estimate of the relative abundances of all 34 lecithotrophic y-naupliar morphospecies is presented, based on laboratory-reared final-instar specimens. This treatment is intended as a step towards a proper taxonomy and a revised classification of Facetotecta, which will involve detailed descriptions of both nauplii and cyprids. Until such work progresses, the present overview of the y-naupliar fauna of a single Okinawan locality known to be a hotspot of y-larval diversity is offered as a baseline for further surveys of Facetotecta elsewhere in the Indo-West Pacific and beyond.
Taxonomic analysis of the genital plates and associated structures in Ophiuroidea (Echinodermata)
(2024)
Recently, new insights have been gained from the ophiuroid skeleton that were instrumental in the inference of a new phylogeny. The so far least studied ossicles are the adradial and abradial genital plates and the radial shields, which articulate with each other and support the genital slit and disc. In addition, the inner sides of the oral shields and madreporites have never been examined in detail. The present study utilized SEM, micro-CT and digital photography to document and examine these structures in 57 species from 28 of the currently accepted 34 families of Ophiuroidea. Early ontogeny and fossils were also considered. Previously, mainly the articular structures had been analysed, but the overall shape of the genital plates was here found to hold important phylogenetic signals. A long-neglected ossicle was re-discovered and studied in detail for the first time, here named the oral genital plate. It was recognized in all Ophintegrida, but was found to be absent in all Euryophiurida. The oral genital plate articulates with the oral shield and supports the proximal part of the genital slit wall. Abradial and oral genital plates were found to be absent in species that lack genital slits, but the adradial genital plate was always present. Numerous new morphological characters with potential phylogenetic signals were identified, described and figured in detail. A pre-existing character matrix was extended and revised with these new data, as well as with recently revised data on oral papillae, and a Bayesian phylogenetic analysis was performed. This phylogeny largely agrees with the current molecular hypothesis, but some branches were not supported.
Three new species of the genus Pelodera Schneider, 1866 viz., P. indica sp. nov., P. adeeli sp. nov. and P. paratretzeli sp. nov. collected from dung beetles and P. cylindrica (Cobb, 1898) collected from soil samples, are described and illustrated. Pelodera indica sp. nov. is characterised by sexual dimorphism in anterior region, cupola-shaped tail with a spike; males having punctated, striated and lobed bursa with no genital papillae originating anterior to cloaca. Pelodera adeeli sp. nov. is characterised by coarsely annulated cuticle; relatively narrow stoma; tail conoid without spike; males with punctated, lobed bursa and nine pairs of genital papillae arranged in a 2/1+2+P+3+1 configuration. Pelodera paratretzeli sp. nov. is characterised by sexual dimorphism in anterior region, stoma wide with three well-developed metastegostomal denticles; tail cupola-shaped with a long spike; males having spicules fused distally up to 12–14% of spicule length; bursa peloderan, anteriorly closed and punctated with nine pairs of genital papillae arranged in a 3/2+P+3+1 configuration. Pelodera cylindrica is described with additional details. The comparative analysis as well as phylogenetic relationship of the species belonging to the coarctata group have been elaborated by incorporating scanning electron microscopic observations. Information on the biogeographical distribution has also been provided.
When experienced in-person, engagement with art has been associated with positive outcomes in well-being and mental health. However, especially in the last decade, art viewing, cultural engagement, and even ‘trips’ to museums have begun to take place online, via computers, smartphones, tablets, or in virtual reality. Similarly, to what has been reported for in-person visits, online art engagements—easily accessible from personal devices—have also been associated to well-being impacts. However, a broader understanding of for whom and how online-delivered art might have well-being impacts is still lacking. In the present study, we used a Monet interactive art exhibition from Google Arts and Culture to deepen our understanding of the role of pleasure, meaning, and individual differences in the responsiveness to art. Beyond replicating the previous group-level effects, we confirmed our pre-registered hypothesis that trait-level inter-individual differences in aesthetic responsiveness predict some of the benefits that online art viewing has on well-being and further that such inter-individual differences at the trait level were mediated by subjective experiences of pleasure and especially meaningfulness felt during the online-art intervention. The role that participants' experiences play as a possible mechanism during art interventions is discussed in light of recent theoretical models.
Two species of the genus Ophelina Örsted, 1843 (Annelida, Opheliidae) are reported from the coast of Kuwait (Arabian Gulf) after specimens collected in the intertidal and shallow subtidal, namely Ophelina arabica sp. nov. and Ophelina grandis (Pillai, 1961). The new species is mainly characterised by features of the anal tube, which is provided with about 25 annulations at each side; the ventral margins are fully fused while dorsal margins are fused at most of their length but are free at the distal end in the shape of a conspicuous incision; the posterior end is opened with free margins; the anal tube also lacks marginal papillae but bears a pair of basal papillae and an unpaired anal cirrus attached to ventral margin at mid-length. Ophelina grandis is reported for the first time in the Arabian Gulf; specimens are fully described and compared with similar species. A key for species of Ophelina in the Indo-Pacific, Southern Asia, Indo-Malay Archipelago and Australia, is also provided.
Benthic samples were collected during two expeditions near the Antarctic Peninsula and in the South-Eastern Weddell Sea. During these studies, a new species of Ampharetidae Malmgren, 1867, Anobothrus konstantini Säring & Bick sp. nov., was found. Here we present a detailed description of this species. We used the traditional light microscope and scanning electron microscope (SEM) to identify and describe the diagnostic characters: a circular glandular band on segment 6; an elongate ridge between the notopodia on segment 12 and modified notochaetae on this segment; 16 thoracic, two intermediate and ten abdominal segments. For the first time, micro-computed tomography (micro-CT) was used for a species description of Anobothrus. Micro-CT provided information on the shape of the prostomium (Ampharete-type) and the arrangement of branchiae (four pairs in two rows, without a gap). In addition, we provide quantitative information on the environmental niche based on sediment parameters (chlorophyll a content, organic matter content, chloroplast equivalent, grain size) for the new Anobothrus species, relevant for, e.g., species distribution modelling. Finally, an identification key for all Anobothrus species is provided.
Six new species of Zaischnopsis Ashmead (Hymenoptera: Eupelmidae) from China are described, Zaischnopsis covid Jiang & Peng sp. nov., Zaischnopsis fuscolivida Tang & Peng sp. nov., Zaischnopsis lii Jiang & Peng sp. nov., Zaischnopsis pacis Jiang & Peng sp. nov., Zaischnopsis campaniformis Tang & Peng sp. nov., and Zaischnopsis zhongi Jiang & Peng sp. nov. All the new species are described and illustrated based on females, and partial mitochondrial cytochrome oxidase subunit I (COI) sequences are provided for the six new species as well as for the previously described Z. fumosa Peng & Xiang. Females of all the species of Zaischnopsis recorded from China are differentiated in a key.
Based on samples collected during the BIOICE project off Iceland, four species of marine annelids belonging to the family Pectinariidae were identified: Amphictene auricoma (O.F. Müller, 1776), Cistenides granulata (Linnaeus, 1767), Cistenides hyperborea Malmgren, 1865 and Lagis koreni Malmgren, 1866. Taxonomic remarks and data on geographical and bathymetric distribution are presented. The distribution of each species off Iceland was evaluated and two patterns were defined: C. granulata and C. hyperborea were mainly found in waters off the northeast coast, while A. auricoma and L. koreni were found on the southern coast. Several body characters with taxonomic value in this family were reviewed under the stereo microscope and scanning electron microscope, with special emphasis on the neuropodial uncini. Remarks on these special chaetae are included in the diagnoses.
Necropsies of Baltic grey (Halichoerus grypus) and ringed seals (Pusa hispida) presented a rare opportunity to study their acanthocephalan fauna. Both species hosted adults of three species of the genus Corynosoma Lühe, 1904, namely C. magdaleni Montreuil, 1958, C. semerme (Forsell, 1904) Lühe 1911 and C. strumosum (Rudolphi, 1802) Lühe 1904. A comparative morphological analysis of these three species of Corynosoma, combining both light and scanning electron microscopy, was performed for the first time. Sexual dimorphism in the size and shape of the trunk was observed in both C. magdaleni and C. semerme, but there was insufficient material to investigate this phenomenon in C. strumosum. Genital spines were not observed in any of the female acanthocephalans. Three possible explanations for the presence of genital spines in some females, but not others are (i) cryptic speciation, (ii) phenotypic variation and (iii) loss by extraction or shearing when the copulatory cap is released. Copulatory caps were observed on female C. semerme. The size and morphology showed considerable variability and all caps were strongly autofluoresecent.