Comparative anatomy of the rostrosoma of Solifugae, Pseudoscorpiones and Acari

We compare the microscopic anatomy of the mouthparts of representative species of Solifugae, Pseudoscorpiones and Parasitiformes (Acari). Specifically, we focus on the epistome, the labrum, the lateral lips (= endites of the pedipalpal coxae) and the musculature of the pharyngeal suction pump. We provide evidence that the labrum is reduced in Solifugae, but present and functional in Pseudoscorpiones and Acari. The epistome constitutes the entire dorsal face of the rostrosoma in Solifugae, but is internalized into the prosoma in Pseudoscorpiones. In Acari, the epistome shows an ancestral morphology, probably close to the ground pattern of chelicerates. The lateral lips of Solifugae contribute to the ventral face of the rostrosoma and the two lips of the mouth opening. In Solifugae, the ventral rostrosoma also includes a sclerite that might derive from a tritosternum. In Pseudoscorpiones, the lateral lips remain independent of the rostrosoma, they interlock ventral to the rostrosoma forming a perioral space. Here, the rostrosoma has an unpaired ventral lip of unresolved morphological origin, which is, however, clearly distinct from the lateral lips of Solifugae. The pharyngeal suction pump differs in all three clades in attachment, number of muscles and origin of muscles. We interpret the data as evidence for independent, parallel evolution of elements of the ground pattern of the (eu)chelicerate mouth parts. Based on the morphological elements of a common euchelicerate ground plan, the rostrosoma evolved independently in the three clades. We reject earlier hypotheses that consider the rostrosoma a character to support a phylogenetic relationship of the three clades.

Wing interference patterns are consistent and sexually dimorphic in the four families of crane flies (Diptera, Tipuloidea)

Wing interference patterns (WIP) are stable structural colors in insect wings caused by thin-film interference. This study seeks to establish WIP as a stable, sexually dimorphic, species-level character across the four families of Tipuloidea and investigate generic level WIP. Thirteen species of Tipuloidea were selected from museum specimens in the Academy of Natural Sciences of Drexel University collection. One wing from a male and female of each representative species was excised and mounted to a slide with coverslip, placed against a black background, and imaged using an integrated microscope camera. Images were minimally retouched but otherwise unchanged. Descriptions of the WIP for each sex of each species are provided. Twelve of thirteen species imaged had WIP, which were stable and species specific while eight of those twelve had sexually dimorphic WIP. Comparisons of three species of Nephrotoma were inconclusive regarding a generic level WIP. Gnophomyia tristissima had higher intraspecific variation than other species examined. This study confirms stable, species specific WIP in all four families of crane flies for the first time. More research must be done regarding generic-level stability of WIP in crane flies as well as the role sexual and natural selection play in the evolution of wing interference patterns in insects.

Taxonomic, morphometric and limnological assessment of the commercially important ichthyofauna of Sakhakot Stream, Malakand, Pakistan

The present study was conducted for the taxonomic, morphometric and limnological assessment of the commercially important ichthyofauna of Sakhakot Stream, Malakand, Pakistan. The study area was divided into three sites along the water course namely Dargai Stream, Sakhakot Stream and Shergarh Stream. Fish samples were collected randomly during January to August 2017 with the help of fish gears. A taxonomic key was designed for the collected fish specimens. Ten fish species were identified belonging to 3 orders and 4 families. Family Cyprinidae was the dominant family with seven representative species while families Siluridae, Nemacheilidae and Mastacembelidae were represented by one species each. Lower mean total length and standard length was recorded in Puntius conchonius (Hamilton, 1822) as 9.2 ± 0.6 cm and 7.3 ± 0.6 cm respectively, while highest mean total length and standard length was recorded in Mastacembelus armatus (Lacepede, 1800) as 28.1 ± 1.7 cm and 15.9 ± 2.4 cm respectively. Mean pH of the water ranged from 6.1 at Shergarh Stream in August to 8.7 at Sakhakot Stream in January. Average temperature range was recorded from 10.9 °C in January at Dargai Stream to 18.7 °C in August at Shergarh Stream. No statistically significant difference was found for temperature (p = 0.96) and pH (p = 0.14) in the three water streams. The present study will provide a baseline for the rearing and enhancement of wild stock of the commercially important ichthyofauna in the field of aquaculture and fisheries.

MOLLUSCS FROM THE UPPER MESOPHOTIC ZONE IN A SCARCELY KNOWN REEF OF THE WESTERN EQUATORIAL ATLANTIC

Despite the increasing focus on biodiversity of mesophotic coral ecosystems (MCEs) on a global scale, some biological groups, such as molluscs, are still poorly investigated. The taxonomic diversity of the molluscan fauna of a scarcely known MCE of the Western Equatorial Atlantic, Northeastern Brazil, was surveyed. Samples were collected along the shallower strata of the upper mesophotic zone (between 33-36 m depth). Twenty-one taxa (nine species of gastropods, ten species of bivalves, and two taxa of chitons) were listed, two of which (Novastoa sp. and Thylaeodus sp.) are potential endemic species. A new northern limit of distribution of Persicula moscatellii was established and seven species had new bathymetric records for living specimens (Barbatia domingensis, Barbatia cancellaria, Lamychaena hians, Leiosolenus bisulcatus, Pinctada imbricata, Hipponix incurvus, and Persicula moscatellii). Hipponix costellatus are the most representative species with 49 individuals, followed by Lima caribaea with six individuals. The present work is the first contribution to the knowledge of the molluscan fauna associated with consolidated substrates from this little-known MCE. Keywords: mesophotic coral ecosystems, tropical reef, molluscan diversity, Brazilian Province, conventional SCUBA.

Understanding Nutrition and Metabolism of Threatened, Data-Poor Rheophilic Fishes in Context of Riverine Stocking Success-Barbel as a Model for Major European Drainages?

Large-bodied, river-migrating, rheophilic fishes (cyprinids) such as barbel Barbus barbus, nase Chondrostoma nasus, asp Leuciscus aspius, and vimba bream Vimba vimba are threatened in major European drainages. This represents the subject of our present study. Their hatchery nutrition prior to river-release is mostly on a hit-and-trial or carp-based diet basis. The study demonstrates an alternative approach to decide optimum nutrition for these conservation-priority and nutritionally data-poor fishes. The study revealed barbel as a central representative species in terms of wild body composition among other native rheophilic cyprinids considered (asp, nase, vimba bream). Taking barbel as a model, the study shows that barbel or rheophilic cyprinids may have carnivorous-like metabolism and higher requirements of S-containing, aromatic, branched-chain amino acids (AAs) than carps. Besides, there are important interactions of AAs and fatty acids (FAs) biosynthesis to consider. Only proper feeding of nutritionally well-selected diets may contribute to river stocking mandates such as steepest growth trajectory (≈less time in captivity), ideal size-at-release, body fitness (≈blend-in with wild conspecifics, predator refuge), better gastrointestinal condition, maximized body reserves of functional nutrients, and retention efficiencies (≈uncompromised physiology). Considering important physiological functions and how AA–FA interactions shape them, hatchery-raised fishes on casually chosen diets may have high chances of physiological, morphological, and behavioral deficits (≈low post-stocking survivability). Based on the observations, optimum nutrient requirements of juvenile (0+ to 1+ age) barbels are suggested. Future efforts may consider barbels as a nutrition model for conservation aquaculture of threatened and data poor rheophilic cyprinids of the region.

New Models to Predict the Acute and Chronic Toxicities of Representative Species of the Main Trophic Levels of Aquatic Environments

To assess the impact of chemicals on an aquatic environment, toxicological data for three trophic levels are needed to address the chronic and acute toxicities. The use of non-testing methods, such as predictive computational models, was proposed to avoid or reduce the need for animal models and speed up the process when there are many substances to be tested. We developed predictive models for Raphidocelis subcapitata, Daphnia magna, and fish for acute and chronic toxicities. The random forest machine learning approach gave the best results. The models gave good statistical quality for all endpoints. These models are freely available for use as individual models in the VEGA platform and for prioritization in JANUS software.

A revised infrageneric classification of Bellevalia Lapeyr. (Asparagaceae: Scilloideae) based on molecular analysis

Within the genus Bellevalia (Asparagaceae: Scilloideae: Hyacintheae), flower shape and colour, the ratio of leaf to scape length, and the orientation of the pedicels were traditionally used to delimit sections, subsections and species. We conducted a phylogenetic analysis of representative species from sections Bellevalia, Conicae, Nutantes and Oxydontae, representing four out of the six sections that are currently recognised, using the four chloroplast regions rbcL, matK, trnL intron, and trnL-F spacer. Our results indicate that the sections are not monophyletic as currently circumscribed. Our analyses retrieve two major, well-supported clades. The first clade (sect. Conicae) includes only species with ciliate leaves and green-veined perianth lobes, and the second clade (sect. Bellevalia) includes the species lacking these characteristics. Within the second clade, the species with yellow anthers are separated from those with violet anthers. Our molecular analysis does not support the traditional subdivisions of the genus but establishes the value of cilia on the leaf margin, green veins in the perianths lobes, and the colour of the anthers as indicators of relationships among the species. We recommend that the current four sections and six subsections of Bellevalia be reduced to two sections without subsections and we provide an updated and corrected nomenclature for these sections and subsections, designating lectotypes where necessary.

Evolutionary Tracks of Chromosomal Diversification in Surgeonfishes (Acanthuridae: Acanthurus) Along the World’s Biogeographic Domains

Fishes of the genus Acanthurus (Acanthuridae) are strongly related to reef environments, in a broad biogeographic context worldwide. Although their biological aspects are well known, cytogenetic information related to this genus remains incipient. In this study, Acanthurus species from populations inhabiting coastal regions of the Southwest Atlantic (SWA), South Atlantic oceanic islands (Fernando de Noronha Archipelago and Trindade Island), Greater Caribbean (GC), and Indo-Pacific Ocean (the center of the origin of the group) were analyzed to investigate their evolutionary differentiation. For this purpose, we employed conventional cytogenetic procedures and fluorescence in situ hybridization of 18S rDNA, 5S rDNA, and H3 and H2B-H2A histone sequences. The Atlantic species (A. coeruleus, A. chirurgus, and A. bahianus) did not show variations among them, despite their vast continental and insular distribution. In contrast, A. coeruleus from SWA and GC diverged from each other in the number of 18S rDNA sites, a condition likely associated with the barrier created by the outflows of the Amazonas/Orinoco rivers. The geminate species A. tractus had a cytogenetic profile similar to that of A. bahianus. However, the chromosomal macrostructures and the distribution of rDNA and hisDNA sequences revealed moderate to higher rates of diversification when Acanthurus species from recently colonized areas (Atlantic Ocean) were compared to A. triostegus, a representative species from the Indian Ocean. Our cytogenetic data covered all Acanthurus species from the Western Atlantic, tracked phylogenetic diversification throughout the dispersive process of the genus, and highlighted the probable diversifying role of ocean barriers in this process.

Cytometric Analysis of Diverse Glaucophyte Species Reveals Distinctive Signals Useful for Fluorescence-Based Detection and Sorting

Glaucophytes, red algae and viridiplants (green algae and land plants) are formally united in the supergroup Archaeplastida. Although diverse molecular and genomic evidence suggest the common origin of the three Archaeplastida lineages, the lack of a robust glaucophyte knowledgebase has limited comprehensive evaluations of competing hypotheses. Glaucophytes are rare and apparently confined to freshwater habitats. However, the distribution and diversity of these algae have not been thoroughly explored owing to challenges with detecting and isolating novel specimens. Here we examined the cytometric signatures of representative species of the genera Cyanophora, Cyanoptyche, Glaucocystis and Gloeochaete for a distinctive signal that would aid identification. Most glaucophytes analyzed presented a relatively high red fluorescence signal due to the presence of the blue phycobiliproteins C-phycocyanin and allophycocyanin. Cell-size differences and the concurrent presence of the red phycobiliprotein phycoerythrin in other algal lineages, such as red algae and cryptophytes, allowed us to distinguish glaucophytes from other photosynthetic cells containing blue phycobiliproteins. We used fluorescence-assisted cell sorting (FACS) to isolate viable Cyanophora and Glaucocystis individuals from existing cultures. Our results indicate that the peculiar autofluorescence signal of glaucophytes will facilitate further identification and isolation on novel specimens of this scarce but important algal group.

Developing an efficient DNA barcoding system to differentiate between Lilium species

Background Lilium is an important ornamental bulb, possesses medicinal properties, and is also edible. Species within the Lilium genus share very similar morphology and macroscopic characteristics, thus they cannot be easily and clearly distinguished from one another. To date, no efficient species-specific markers have been developed for classifying wild lily species, which poses an issue with further characterizing its medicinal properties. Results To develop a simple and reliable identification system for Lilium, 45 representative species from 6 sections were used to develop a DNA barcoding system, which was based on DNA sequence polymorphisms. In this study, we assessed five commonly used DNA barcode candidates (ITS, rbcL, ycf1b, matK and psbA-trnH) and five novel barcode candidates obtained from highly variable chloroplast genomic regions (trnL-trnF, trnS-trnG, trnF-ndhJ, trnP-psaJ-rpI33 and psbB-psbH). We showed that a set of three novel DNA barcodes (ITS + trnP-psaJ-rpI33 + psbB-psbH) could be efficiently used as a genetic marker to distinguish between lily species, as assessed by methods including DNAsp, BI and ML tree, and Pair Wise Group (PWG). Conclusions A rapid and reliable DNA barcoding method was developed for all 45 wild Lilium species by using ITS, trnP-psaJ-rpI33, and psbB-psbH as DNA barcoding markers. The method can be used in the classification of wild Lilium species, especially endangered species, and also provides an effective method for selective lily breeding.