Diversity in parasitic helminths of Australasian marsupials and monotremes: a molecular perspective

Marsupials and monotremes are a prominent part of the mammalian fauna in Australia, and harbour an extremely diverse and highly distinctive array of helminth parasites. Their study has been relatively neglected, likely because they have no direct, adverse socioeconomic impact. As the body plans of helminths generally are very simple and morphological characterisation likely underestimates true diversity, molecular tools have been employed to assess genetic diversity. Using biochemical and/or molecular methods, recent studies show extensive diversity in helminths of marsupials, with cryptic species being commonly encountered. The purpose of this article is to review current knowledge about the diversity of parasitic helminths of marsupials and monotremes, to raise questions as to whether current molecular data can be used to estimate diversity, what mechanisms lead to such diversity, to critically appraise the molecular tools that have been employed thus far to explore diversity and to discuss the directions which might be taken in the future employing improved techniques.     

The role of the anthropogenic Allee effect in the exotic pet trade on Facebook in Thailand

The impact of the wildlife trade has been accentuated in the Internet age where social media platforms have offered accessible and consumer-friendly avenues in the way species are legally and illegally traded. We explored the exotic pet trade on a social media platform, Facebook, in Thailand. Over the 18-month period, we recorded 761 posts of primates and carnivores’ species, totalling 1190 individuals from 42 species.Using Generalised Linear Models, we developed hypotheses to explain price dynamics. Variables include, species’ native status (if species are found in Thailand), domestic protection (if species are protected under Thai wildlife laws), international regulation (species CITES listing) and species threatened status (species IUCN Red Listing). Overall, we found evidence of an anthropogenic Allee effect where exotic imports from South America and Africa were significantly more expensive than native species (Wald χ² = 969.72, df = 13, p < 0.05). Trade in these legally imported non-native wildlife species contributed to 11% of posts. Illegal trade of native species contributed to 66% of posts. When considering only native species, trends toward an anthropogenic Allee effect were observed where protected illegal species called for higher prices than legal species.Illegal wildlife trade on Facebook was blatant, easily accessible and unchecked. Discrepancies in current domestic wildlife legislation lead to intentional evasion of laws and a lack of enforcement. Disproportionate desire for rare or protected species encourages a cycle of exploitation that threatens species to extinction.     

Risk assessment of the crayfish pet trade based on data from the Czech Republic

The pet trade in freshwater crustaceans, including crayfish, has grown rapidly in recent decades and become an important pathway for introducing new non-indigenous species into Europe. This paper provides the first overview of non-indigenous crayfish species (NICS) traded as ornamental and their potential impact in the Czech Republic, which is the second leading importer into Europe. The paper presents a full list of traded crayfish species, their market availability, and trade names or misnomers used in the country. In total, 27 crayfish species from all three families are advertised and marketed, of which Astacus astacus is the only indigenous species. Only three NICS were recognized as very common on the market. The invasiveness and risk associated with ornamental crayfish trade were assessed using the Freshwater Invertebrate Invasiveness Scoring Kit. Five NICS were classified into the high-risk category, the highest score being for Procambarus fallax f. virginalis. The invasiveness of crayfish indigenous to North America is significantly greater than that of crayfish from the rest of the world, and therefore regulation in this regard is recommended.     

Establishment risk and potential invasiveness of the selected exotic amphibians from pet trade in the European Union

The pet trade has grown in recent years and become the most important pathway for the introduction of non-indigenous species of amphibians and reptiles worldwide. Amphibians traded on the pet market have been widely overlooked in systematic invasion studies, so their establishment potential and invasion dynamics remain poorly understood, despite the fact that the impact of invaders from this taxonomic group on native biota may be considerable. The determination of the most common species of amphibians traded as pets was based on a survey of the market in the Czech Republic, which is an export hub for ornamental aquatic animals into the European Union (EU). Subsequently, the establishment potential of the most common species for EU was determined using a proven risk assessment model. Amphibians that scored higher than the established species Xenopus laevis were additionally evaluated for their invasion potential using the Amphibian Invasiveness Screening Kit (AmphISK).Sixteen species of amphibians in pet market (14 Anura, 2Caudata) have an establishment potential in the EU. However, none of these species have reached the invasion potential score of already spreading species X. laevis and Lithobates catesbeianus. The species closest to the threshold value were Lithobates pipiens and Pelophylax saharicus. Amphibians represent a rather small group within all traded animals but this fact should not lead us to an underestimation of their potential invasiveness.     

Positive selection of beautiful invaders: long-term persistence and bio-invasion risk of freshwater crayfish in the pet trade

After interest in keeping crayfish (Crustacea, Decapoda, Astacida) in home aquaria peaked in the mid-2000s, the aquarium trade has become a novel introduction pathway for non-native crayfish species in Germany. Here, we provide an update on the ornamental crayfish trade approximately one decade after the ‘crayfish hype’ to explore the long-term implications in terms of bio-invasion risk. Specifically, species’ availability in e-commerce and potential invasiveness were assessed and compared to previous studies. Morphological and ecological traits of the offered species were compiled and related to their long-term availability (covering 2005–2015). In July 2015, a total of 31 online shops offered 28 crayfish species, which represents a decline of 24 % in species diversity compared to the late 2000s. The estimated rate of import of new species has considerably flattened and approaches pre-hype values (<1 species year^?1). However, the risk associated with the offered species, as assessed by a risk screening tool, has not decreased compared to the late 2000s. Long-term availability in the trade was primarily determined by bright coloration, the ability to reproduce under warm aquarium conditions, and a preference for lentic habitats. Species featuring such traits are likely to persist in the aquarium trade and include four high-risk species, most notably invasive and crayfish plague-carrying red swamp crayfish (Procambarus clarkii) and Marmorkrebs (Procambarus fallax f. virginalis). Persistent propagule pressure from aquaria has substantially contributed to the establishment of both species in Germany, stressing the need for more effective pathway management.     

Assessing the taxonomic resolution of southern African trapdoor spiders (Araneae: Ctenizidae; Cyrtaucheniidae; Idiopidae) and implications for their conservation

Taxonomic classifications simultaneously represent hypotheses of taxon identity and relationships to taxonomists, and real, unchanging entities to users of taxonomic information. Taxonomic changes, while representing scientific progress, can be a source of frustration for users. A method for assessing confidence in the taxonomy of a group of organisms would assist users of the taxonomy. A method is presented for determining the degree of development of a taxonomy, a concept termed ‘taxonomic resolution’. The method was applied to six groups of southern African mygalomorph trapdoor spiders, namely Stasimopus Simon 1892 (Ctenizidae Thorell 1877), Ancylotrypa Simon 1889 (Cyrtaucheniidae Simon 1889), four genera of Idiopidae Simon 1889 assessed as a single group, Galeosoma Purcell 1903, the families Migidae Simon 1889 and Microstigmatidae Roewer 1942, and the burrowing scorpion genus Opistophthalmus C. L. Koch 1837 (Scorpionidae Latreille 1802). The method was based on the assumption that species delimitation in a group of organisms, the taxonomy of which is based on morphological characters, depends on whether the sample of material examined is adequate for assessing variation in those characters. Five assessment criteria were identified and scored for a group of species using the taxonomic literature. Estimates of the number of species remaining to be discovered and described in each group were also included in the assessment. The results obtained for the trapdoor spiders ranged from 15 to 29%, indicating a potentially significant degree of uncertainty in the taxonomy. Results for Migidae and Microstigmatidae were 51 and 78% respectively, whereas the result for Opistophthalmus was 93%. The applied value of a measure of taxonomic resolution, the limitations of the method, and a strategy for developing a more generally applicable method are discussed.     

An assessment of West African seahorses in fisheries catch and trade

This study provides the first assessment of a heavily traded West African seahorse species, Hippocampus algiricus, and the first information on short‐snouted seahorse Hippocampus hippocampus biology in Africa. A total of 219 seahorses were sampled from fisher catch in Senegal and The Gambia, with estimated height at reproductive activity for H. algiricus (161 mm) larger than mean ± s.d . catch height (150 ± 31 mm). Catch composition, height at reproductive activity and potential biases in fishery retention are discussed with regard to the current Convention on International Trade of Endangered Species (CITES) guidelines.     

Checklist of African Tischeriidae (Insecta: Lepidoptera) with a redescription of the formerly neglected Tischeria urticicolella from Equatorial Africa

Tischeria urticicolella (Ghesquière, 1940)--a poorly studied species from the Democratic Republic of Congo and formerly known as a member of the Gracillariidae--is redescribed and reported as belonging to the Tischeriidae for the first time. The external features and male genitalia are figured and described. A checklist and distribution map for all 18 Tischeriidae species currently recorded from Africa (including the Canary Islands) are given.     

Concurrence of Eimeria and helminth parasitic infections in West African Dwarf kids in Ghana

The sequence of appearance of Eimeria and helminths, in 20 West African Dwarf kids from birth and the pattern of oocyst and strongyle worm egg output for 1.5 years are described. Eimeria oocysts appeared early about 20 days after birth and oocyst output in some kids reached 2.7 million oocysts per gram (opg) of faeces about 39 days after birth and showed a group mean oocyst output of 443,540 opg in the second month but this declined further to 23,840 opg after 5.5 months. Eimeria arloingi (20.50%), Eimeria ninakohlyakimovae (17.02%), Eimeria alijevi (15.07%), Eimeria caprina (12.65%), Eimeria jolchijevi (11.42%), Eimeria apsheronica (8.70%), Eimeria pallida (5.31%), Eimeria caprovina (3.29%), Eimeria hirci (3.20%) and Eimeria christenseni (2.84%) were seen in a descending order of prevalence. Strongyle worm ova were seen 53 days after birth and peaked soon after the fall in Eimeria oocyst output but thereafter fluctuated. The eggs of cestode, Moniezia spp. appeared later but was transient. Both oocyst and worm egg output declined and were almost absent when the kids were about 1 year old. Faecal larval cultures were made and the L₃s identified with the dominant ones being Haemonchus spp. and Trichostrongylus spp. Sixty percent of the kids in this study died when they were 7 months old and a total of 70% of the kids had died before they were 1 year old.