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bioRxiv2017

Hematology, biochemistry, and toxicology of wild hawksbill turtles (Eretmochelys imbricata) nesting in mangrove estuaries in the eastern Pacific Ocean

Sea turtles are a keystone species and are highly sensitive to changes in their environment, making them excellent environmental indicators. In light of environmental and climate changes, species are increasingly threatened by pollution, changes in ocean health, habitat alteration, and plastic ingestion. There may be additional health related threats and understanding these threats is key in directing future management and conservation efforts, particularly for severely reduced sea turtle populations. Hawksbill turtles (Eretmochelys imbricata) are critically endangered, with those in the eastern Pacific Ocean (Mexico-Peru) considered one of the most threatened sea turtle populations in the world. This study establishes baseline health parameters in hematology and blood biochemistry as well as tested for heavy metals and persitent organic pollutants in eastern Pacific hawksbills at a primary nesting colony located in a mangrove estuary. Whereas hematology and biochemistry results are consistent with healthy populations of other species of sea turtles, we identified differences in packed cell volume, heterophils and lympohcyte counts, and glucose when comparing our data to other adult hawksbill analysis (1), (2), (3). Our analysis of heavy metal contamination revealed a mean blood level of 0.245 ppm of arsenic, 0.045 ppm of lead, and 0.008 ppm of mercury. Blood levels of persistent organic pollutants were below the laboratory detection limit for all turtles. Our results suggest that differences in the feeding ecology of eastern Pacific hawksbills in mangrove estuaries may make them less likely to accumulate persistent organic pollutants and heavy metals in their blood. These baseline data on blood values in hawksbills nesting within a mangrove estuary in the eastern Pacific offer important guidance for health assessments of the species in the wild and in clinical rehabilitation facilities, and underscore the importance of preventing contamination from point and non-point sources in mangrove estuaries, which represent primary habitat to hawksbills and myriad other marine species in the eastern Pacific Ocean.

zoology↗

bioRxiv2018

Identification of the Goliath beetles Fornasinius fornasini Bertoloni and Fornasinius hauseri Kraatz (Scarabaeidae: Cetoniinae)

The Goliath beetles (subtribe Goliathina) are large Cetoniinae comprising a few highly related genera broadly distributed in sub-Saharan Africa. The genus Fornasinius Bertoloni was established in 1853 by Giuseppe Bertoloni to receive a taxon that was sufficiently distinct from the known representatives of the genus Goliathus Lamarck to merit a different placement. In spite of their large size and showy appearance, the members of the genus Fornasinius are poorly known. Here, the type species of the genus, F. fornasini Bertoloni, 1853 (type locality: Mozambique), is identified and re-described. It has emerged that F. fornasini Bertoloni has been misidentified after its original description and that only a few specimens are known of this species. F. fornasini sensu auct. (nec Bertoloni) is instead referable to another taxon, F. hauseri Kraatz, 1896 sp. bon., of which three subspecies can be distinguished: F. hauseri s. str., from south-central Kenya and possibly Cameroon; F. hauseri ssp. hirthi Preiss, 1904 stat. rev., from the Lake Victoria region and northern Tanzania; and a new subspecies to be described from south-east Democratic Republic of the Congo.

zoology↗

bioRxiv2018

The Impact of fodder on Bombyx Mori

Silk production by the Chilean silkworm, although an important source of revenue, has not been extensively studied. In the current study, we research 564 Mountain Silkworm (Bombyx mori), analyzing their silk harvests, silk production incubation periods and demographic profiles. The mountain silkworms were randomly divided into two clusters (cluster#1, cluster#2), each of which had 56 mountain silkworms. Crumpled maize were replaced by steam-flaked maize 30%, 50%, 100%, then researched the effects of nourishing steam-flaked maize on production performance of silk production by silkworm. The outcomes showed that the cluster#2 had better median silk harvest than cluster#1, the mean of these increment silk harvests was 3.48pounds (P-value <0.05); the protein proportion and the sugar in silk of cluster#2 went up than cluster#1; for the urine nitrogen and somatic cell count of cluster#2 were lower than cluster#1 by 0.9% (P-value >0.05), 30,800 cells/ml (P-value<0.05), respectively. The current research confirmed that utilizing the JHO nutrition heightened silk harvest, improved silk production characteristics, and enhanced the performance of mountain silkworms; furthermore, it heightened resistance to the sickness due to strengthened resistance.

zoology↗

bioRxiv2018

Seasonal physiological responses to heat in an alpine range-restricted bird: the Cape Rockjumper

Hot, dry summer conditions impose physiological stress on endotherms, yet we have a poor understanding of how endotherms seasonally adjust their costs of thermoregulation under hot conditions. We determined whether seasonal phenotypic plasticity in evaporative cooling capacity at high temperatures explained how the range-restricted Cape Rockjumper (Chaetops frenatus; hereafter \"Rockjumper\"), copes with hot and dry summer temperatures of the temperate mountain peaks of southwest South Africa. We measured evaporative water loss (EWL), resting metabolic rate (RMR), and body temperature (Tb) at high air temperatures (30 to 42{degrees}C) of individuals from a wild population of Rockjumpers during winter and summer (n = 11 winter, 4 females, 7 males; n = 10 summer, 6 females, 4 males). We found Rockjumper evaporative cooling in summer imposes higher EWL (i.e. greater water costs) compared to winter, although an accompanying lack of change in RMR resulted in increased summer cooling efficiency. These patterns are similar to those observed in species that inhabit regions where summer temperatures are routinely hot but not water stressed. Our findings show that avian seasonal physiological adjustments to heat can be diverse. Further seasonal studies on thermoregulation in the heat will greatly improve our knowledge of the functional value traits such as evaporative cooling efficiency and heat tolerance hold and how they contribute to the physiological stress organisms experience in heterogenous environments.

zoology↗

bioRxiv2018

Species richness, habitat association and odonata diversity of the south-western region of Bangladesh.

Odonata survey was conducted throughout the south-western region of Bangladesh, concentrated on eight districts and the Sundarban (the largest mangrove forest of the world) from August 2014 to August 2016. A total of 50 species under 30 genera belonging to six families were recorded during the study period. Among the 50 species, 31 species belong to Anisoptera whereas 19 species were recorded from the Zygoptera suborder. Libellulidae and Coenagrionidae were most dominant Anisoptetran and Zygopteran families with 28 and 17 species respectively. One Zygoptera species Mortonagrion varalli was newly added to the Odonata fauna of Bangladesh. Among surveyed habitats, species richness was highest in marshland with 38 species followed by 34 species in the lakeside. On the other hand, odonata diversity was lowest in the mangrove area. Our study shows a positive correlation between environmental variables (such as average rainfall, relative humidity, and average temperature) and species richness in the study area. Species richness is highest during monsoon and lowest in winter.

zoology↗

bioRxiv2018

Woolly ash aphid Prociphilus fraxinifolii (Riley, 1879) (Hemiptera: Eriosomatidae), a new invasive alien pest of ash trees (Fraxinus) in Russia.

Woolly ash aphid or ash leaf curl aphid Prociphilus fraxinifolii (Riley, 1879) is an alien invasive pest of ash trees native to North America. After its first record in Europe in 2003 in Hungary it has spread to the Ukraine, Serbia, Bulgaria, Great Britain, Spain, Poland and Germany. In 2016 P. fraxinifolii was firstly recorded at the southwestern border of Russia. Now Prociphilus fraxinifolii is firstly recorded in the center of European Russia, namely in Moscow Region, which is more than 700 km far from all other known localities of the species. In September 2017 five groups of ash trees (Fraxinus pennsylvanica) with colonies of Prociphilus fraxinifolii were found in Moscow Region. The example of Prociphilus fraxinifolii shows that alien pest insects can spread in Europe very quickly. Now Moscow region is the only regions of Europe, where the expanding range of Prociphilus fraxinifolii has overlapped with expanding ranges of other invasive alien species established in Europe in the last 20 years and severely damaging ash trees: ash dieback fungus Hymenoscyphus fraxineus Baral et al., 2014 (Ascomycota) and emerald ash borer Agrilus planipennis Fairmaire, 1888 (Coleoptera: Buprestidae).

zoology↗

bioRxiv2018

Molecular Typing with COI - DNA Barcode of mosquitoes with medical importance from rural area from La Pintada, Antioquia, Colombia

DNA barcode is a methodology that allows the identification of species using a short fragment of cytochrome oxidase I and library sequences stored in the barcode of life database (bold>), make up an alternative tool for mosquito identification in areas epidemiologically active for arboviruses, protozoa and bacteria. In our study, we collected 114 adult mosquitoes in a rural area in the municipality of La Pintada (Antioquia, Colombia), and were separate for genus and species using morphological keys. Two Legs were taken of specimens mounted, and these were used for DNA extraction, amplification of COI-Barcode through PCR and sequencing. 38 sequences were characterized of seven mosquito species and used in bold> for molecular identification, subsequent characterization of genetic distances intra/interspecies, and MOTUs grouping by neighbor-joining analyses. Seven MOTUs were separate corresponding to seven species identify by morphological keys. bold> was able to identify five species, and two were identified to the genre. The following medically important mosquitoes were recorded in the rural area from La Pintada (Antioquia): Aedes aegypti, Anopheles triannulatus, Coquillettidia nigricans, Mansonia titillans, Ochlerotatus angustivitatus, Psorophora ferox and Psorophora (Grabhamia) sp.

zoology↗

bioRxiv2018

Proteomic analysis of chemosensory organs in the honey bee parasite Varroa destructor: a comprehensive examination of the potential carriers for semiochemicals

The mite Varroa destructor is the major parasite of the honey bee and is responsible for great economical losses. The biochemical tools used by Varroa to detect semiochemicals produced by the host are still largely unknown. We have performed proteomic analysis on chemosensory organs of this species in order to identify putative soluble carriers for pheromones and other olfactory cues emitted by the host. In particular, we have analysed forelegs, mouthparts (palps, chelicera and hypostome) and the second pair of legs (as control tissue) in reproductive and phoretic stages of the Varroa life cycle. We identified 958 Varroa proteins, most of them common to organs and stages. Sequence analysis shows that four proteins can be assigned to the odorant-binding protein (OBP)-like class, which bear some similarity to insect OBPs, but so far are only reported in some Chelicerata. In addition, we have detected the presence of two proteins belonging to the Niemann-Pick family, type C2 (NPC2), which have been suggested to act as semiochemical carriers. This work contributes to elucidating the chemical communication systems in Varroa with the aim of understanding how detection of semiochemicals has evolved in terrestrial non-hexapod Arthropoda. Data are available via ProteomeXchange with identifier PXD008679.

zoology↗

bioRxiv2018

A novel surfactant protein is associated with extrapulmonary respiration in lungless salamanders

Numerous physiological and morphological adaptations were achieved during the transition to lungless respiration following evolutionary lung loss in plethodontid salamanders, including those that enable efficient gas exchange across extrapulmonary tissue. However, the molecular basis of these adaptations is unknown. Here we show that lungless salamanders express in the skin and buccal cavity--the principal sites of respiratory gas exchange in these species--a novel paralog of the gene Surfactant-Associated Protein C (SFTPC), which is a critical component of pulmonary surfactant expressed exclusively in the lung in other vertebrates. The paralogous gene appears to be found only in salamanders, but, similar to SFTPC, in lunged salamanders it is expressed only in the lung. This heterotopic gene expression, combined with predictions from structural modeling and respiratory tissue ultrastructure, suggest that lungless salamanders produce pulmonary surfactant-like secretions outside the lungs and that the novel paralog of SFTPC might facilitate extrapulmonary respiration in the absence of lungs. Heterotopic expression of the SFTPC paralog may have contributed to the remarkable evolutionary radiation of lungless salamanders, which account for more than two thirds of urodele species alive today.

zoology↗

bioRxiv2018

Stress response of Chironomus riparius to changes in water temperature and oxygen concentration in a lowland stream

The increasing impairment of lotic ecosystems has promoted a growing effort into assessing their ecological status by means of biological indicators. While community-based approaches have proven valuable to assess ecosystem integrity, they mostly reflect long-term changes and might not be suitable for tracking and monitoring short-term events. Responses to rapid changes in environmental conditions have been rarely studied under natural conditions. Biomarkers offer the benefit of integrating biological responses at different time scales. Here we used a field experiment to test how the synthesis of heat shock protein 70 (HSP70) and Haemoglobin (Hb) in laboratory-reared larvae of Chironomus riparius (Diptera, Chironomidae) were influenced by short-term changes to water temperature and oxygen concentration in a lowland stream. Our aim was to determine whether HSP70 mRNA expression and Hb content could be used as an in situ \"early warning system\" for freshwater habitats undergoing environmental change. HSP70 exhibited a clear response to changes in temperature measured over a one-day period, confirming its suitability as an indicator of environmental stress. Hb concentration was related to oxygen concentration, but not to temperature. Our findings support the hypothesis that depletion in oxygen induces Hb synthesis in C. riparius larvae. Because tolerance to low oxygen is not only related to total Hb, but also to a more efficient uptake (binding to Hb, e.g. Bohr effect) and release of oxygen to the cell (Root effect), we cannot discern from our data whether increased efficiency played a role. We suggest that C. riparius is a suitable model organism for monitoring sub-lethal stress in the field and that the approach could be applied to other species as more genomic data are available for non-model organisms.

zoology↗

bioRxiv2018

Leg force interference in poly-pedal locomotion

The examination of gaits and gait-changes have been the focus of movement physiology and legged robot engineering since the first emergence of the fields. While most examinations focussed on bipedal and quadrupedal designs many robotic implementations rely on the higher static stability of three or more pairs of legs. Nevertheless, examinations of gait-changes in the biological models, i.e. poly-pedal arthropods such as insects or arachnids, are rare. Except for the well-known change from slow feedback controlled walking to a fast, feedforward controlled running gait, no changes are known or are deemed to be of low significance.\n\nHowever, recent studies in fast moving spiders, mites and cockroaches have revealed an additional gait change also for the transition from intermediate to high running speeds. This change is similar to gait transitions as found in quadrupedal vertebrates.\n\nAccordingly, the present approach aims to extend available theory to poly-pedal designs and examines how the number of active walking legs affects body dynamics when combined with changing duty factors and phase relations. The model shows that higher numbers of active leg pairs can prevent effective use of bouncing gaits such as trot and their associated advantages because significantly higher degrees of leg synchronisation are required. It also shows that small changes in the leg coordination pattern have a much higher impact onto the COM dynamics than in locomotor systems with fewer legs. In this way, the model reveals coordinative constraints for specific gaits facilitating the assessment of animal locomotion and economization of robotic locomotion.\n\nSignificance StatementThe present model approach enables to assess the impact of different numbers of walking legs onto movement dynamics and gait choice in terrestrial legged locomotion. The models results are indicatory for research in legged locomotion regardless whether biological examples or legged walking machines are considered. The approach is suitable for all numbers of pairs of walking legs larger than two and is focussed on symmetrical gaits as found in straight and continuous locomotion. The model fills a gaping gap as the impact of phase shifts among the legs in the coordinated sets of legs typical for poly-pedal animals and robots on overall body dynamics are not considered sufficiently in existing dynamic model approaches.

zoology↗

bioRxiv2018

Quantifying the unquantifiable: why Hymenoptera -- not Coleoptera -- is the most speciose animal order

BackgroundWe challenge the oft-repeated claim that the beetles (Coleoptera) are the most species-rich order of animals. Instead, we assert that another order of insects, the Hymenoptera, are more speciose, due in large part to the massively diverse but relatively poorly known parasitoid wasps. The idea that the beetles have more species than other orders is primarily based on their respective collection histories and the relative availability of taxonomic resources, which both disfavor parasitoid wasps. Though it is unreasonable to directly compare numbers of described species in each order, the ecology of parasitic wasps - specifically, their intimate interactions with their hosts - allows for estimation of relative richness. We present a simple logical model that shows how the specialization of many parasitic wasps on their hosts suggests few scenarios in which there would be more beetle species than parasitic wasp species. We couple this model with an accounting of what we call the \"genus-specific parasitoid-host ratio\" from four well-studied genera of insect hosts, a metric by which to generate extremely conservative estimates of the average number of parasitic wasp species attacking a given beetle or other insect host species. Synthesis of our model with data from real host systems suggests that the Hymenoptera may have 2.5 - 3.2x more species than the Coleoptera. While there are more described species of beetles than all other animals, the Hymenoptera are almost certainly the larger order.

zoology↗

bioRxiv2018

Interplay of size and shape in miniaturized land snails

The distribution of the mean greater shell dimensions of 2446 genera of stylommatophoran land snails consists of two groups peaking at 3 mm and 15.3 mm. The 3-mm group includes the miniature snails whose adult shell dimensions range from almost 0.8 mm to less than 1.5 mm. Relative surface area, shell thickness and egg size are discussed as potential factors that may limit the minimum shell dimensions. To obtain uniform distributions, the shell shape is expressed as the expanse angle, defined as the apex angle of a right triangle the height and the base of which are the shell height and diameter, respectively. In terms of expanse angles there are three shell shapes: tall (< 40{degrees}), flat (> 50{degrees}) and roughly equiaxial (40{degrees}-50{degrees}). The variation of shell shape with size was analyzed within the morphospace they form. At shell dimensions above 10 mm the lowest expanse angle is about 10{degrees}. Below 10 mm, the lower limit of the expanse angle increases as shells get smaller. As a result, no miniature species has a tall shell. It is proposed that two evolutionary functional constraints render small and narrow shells of miniaturized snails nonadaptive. These are the requirements to reduce surface areas to decrease water loss and to have enough volume and a wide enough body whorl to accommodate at least one egg.

zoology↗

bioRxiv2018

Thioredoxins induce oocyte maturation in holothuroids (Echinodermata)

Chromatographic fractions of a rough extract of echinoid spawn (REES) has been demonstrated to efficiently induce oocyte maturation in aspidochirote holothuroids. The method is so efficient that it is now used in holothuriculture to get fertilised eggs even outside the reproductive period of the aquacultured species. We here isolate and identify from echinoid spawns the molecule responsible for the induction of the oocyte maturation in the Mediterranean holothuroid Holothuria tubulosa and the Indo-Pacific Holothuria scabra. The use of proteinase K and dialysing membranes indicates that the active molecule is a protein with a molecular weight superior to 12,000 kDa. The active molecule has been isolated on G-100 Sephadex chromatography column. Active chromatographic fractions include seven proteins identified with nanoLC-MS/MS technique. One of them, identify as a thioredoxin-2 and to which the name Trx-REES has been given, leads up to levels of maturation similar to those obtained with the REES and with a commercial thioredoxin extracted from Escherichia coli. Occurrence of thioredoxin in REES was confirmed by immunoblot analysis, and the maturation-inducing properties of thioredoxin were positively checked in using anti-thioredoxin antibodies. A peptide of 6 AAs corresponding to the active site of Trx-REES, composed of WCNPCK, was synthesised and its efficiency in holothuroid oocyte maturation tested. At some concentrations, the peptide was 1.2 times more active than the REES.

zoology↗

bioRxiv2018

A morphological and molecular analysis of the species diversity of the cichlid genus Petrochromis from Lake Tanganyika (Teleostei: Cichlidae)

A taxonomic revision of the cichlid fish genus Petrochromis endemic to Lake Tanganyika. All recognized taxa are herein described, one subspecies is given species status and five new species, viz. P. calliris, P. daidali, P. heffalumpus, P. lisachisme and P. paucispinis, are presented. P. calliris is described from 6 specimens from Cape Mpimbwe, and distinguished primarily by having a high number of both gill rakers on the lower limb of the first gill arch and vertebrae. P. daidali is described from 18 specimens from Cape Mpimbwe, Kansombo and Nkwazi point, and distinguished primarily by males having a labyrinth-like pattern on the head. P. heffalumpus is described from 7 specimens from Cape Mpimbwe, and distinguished primarily by its great size. P. lisachisme is described from 12 specimens from Cape Mpimbwe and Lyamembe, and distinguished primarily by having a high number of dorsal spines. P. paucispinis is described from 4 specimens from Halembe, and distinguished primarily by having a low number of dorsal spines. A revised key to Petrochromis is included. A phylogenetic tree hypothesis of the genus, based on molecular (mitochondrial cytochrome b and d-loop) and morphological results show that jaw position and number of vertebrae are important diagnostic characters. Analyses suggest that the \"ancestral Petrochromis\" might have looked something like P. orthognathus.

zoology↗

bioRxiv2018

Scute structure reveals sex of juvenile and young sturgeon in caviar aquaculture technology

Sturgeons are valued as specialty black caviar, which is very expensive. Only females are used in the technology of caviar aquaculture. Universal method of sex determination has not yet been developed. Most of known methods are not sufficiently accurate, or used at a relatively late age, or difficult to use. Perfect early determination of sex is considered to be impossible. Because of the dark color of most sturgeon, important morphological differences, which fish of almost all ages have, were overlooked. We first found that the scute structure of Sterlet and Siberian sturgeon depends on the sex, such a pattern is typical for sturgeon of all ages. We found that sex determination is possible at very early stages. Dependencies found with the help of machine learning method open a possibility for creation of sex determination equipment using the artificial intelligence. Our results open a perspective for creation of the sex determination methods for other 23 sturgeon species, which can increase the efficiency of caviar aquaculture and sturgeon restoration in natural waters.

zoology↗

bioRxiv2018

Wide distributions and cryptic diversity within a Microstomum (Platyhelminthes) species complex

Microstomum lineare is a common species of fresh and brackish waters found worldwide. Three genes (18S, CO1, ITS) were sequenced from specimens of M. lineare collected from four countries and the levels of cryptic diversity and genetic structuring was assessed. Results showed M. lineare has very wide haplotype distributions suggesting higher than expected dispersal capabilities. In addition, three new species were described on the basis of molecular taxonomy: Microstomum artoisi sp. nov., Microstomum tchaikovskyi sp. nov., and Microstomum zicklerorum sp. nov.

zoology↗

bioRxiv2018

Chronic exposure to a neonicotinoid pesticide and a synthetic pyrethroid in full-sized honey bee colonies

In the last decade, the use of neonicotinoid insecticides increased significantly in the agricultural landscape and meanwhile considered a risk to honey bees. Besides the exposure to pesticides, colonies are treated frequently with various acaricides that beekeepers are forced to use against the parasitic mite Varroa destructor. Here we have analyzed the impact of a chronic exposure to sublethal concentrations of the common neonicotinoid thiacloprid (T) and the widely used acaricide {tau}-fluvalinate (synthetic pyrethroid, F) - applied alone or in combination - to honey bee colonies under field conditions. The population dynamics of bees and brood were assessed in all colonies according to the Liebefeld method. Four groups (T, F, F+T, control) with 8-9 colonies each were analyzed in two independent replications, each lasting from spring/summer until spring of the consecutive year. In late autumn, all colonies were treated with oxalic acid against Varroosis. We could not find a negative impact of the chronic neonicotinoid exposure on the population dynamics or overwintering success of the colonies, irrespective of whether applied alone or in combination with {tau}-fluvalinate. This is in contrast to some results obtained from individually treated bees under laboratory conditions and confirms again an effective buffering capacity of the honey bee colony as a superorganism. Yet, the underlying mechanisms for this social resilience remain to be fully understood.

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