Monozoic cestodes of the recently amended genus Promonobothrium Mackiewicz, 1968 (Cestoda: Caryophyllidea), parasites of suckers (Cypriniformes: Catostomidae) in North America, are reviewed, with information on their host specificity, distribution and data on the scolex morphology of seven species studied for the first time using scanning electron microscopy (SEM). Evaluation of type and voucher specimens from museum collections and newly collected material of most species indicated the following valid nominal species: Promonobothrium minytremi Mackiewicz, 1968 (type species); P. ingens (Hunter, 1927); P. hunteri (Mackiewicz, 1963); P. ulmeri (Calentine et Mackiewicz, 1966); P. fossae (Williams, 1974) and P. mackiewiczi (Williams, 1974). Rogersus Williams, 1980 with its only species R. rogersi is transferred to Promonobothrium based on morphological and molecular data. Promonobothrium currani sp. n. and P. papiliovarium sp. n. are described from Ictiobus bubalus (Rafinesque) and Ictiobus niger (Rafinesque), and Erimyzon oblongus (Mitchill), respectively. The newly described species can be distinguished from the other congeners by the morphology of the scolex, the position of the anteriormost vitelline follicles and testes, the presence of postovarian vitelline follicles and the shape of the ovary. Molecular phylogenetic analyses of six species based on sequences of the small and large subunits of the nuclear ribosomal RNA genes (ssrDNA, lsrDNA) confirmed the monophyletic status of the genus and supported the validity of the species analysed. A key to identification of all species of Promonobothrium based on morphological characteristics is provided., Mikuláš Oros, Jan Brabec, Roman Kuchta, Anindo Choudhury, Tomáš Scholz., and Obsahuje bibliografii
Lepeophtheirus simplex Ho, Gómez et Fajer-Avila, 2001 is a parasite of Sphoeroides annulatus (Jenyns), an economically important fish species, with potential for aquaculture, in northwestern Mexico. The goal of this study was to describe the developmental stages under experimental conditions and seasonal fecundity of this parasite on wild fish. There are two naupliar, one copepodid, two chalimus and two pre-adult stages preceding the adult of L. simplex. The results support previous findings, which point out that the life cycle of the caligid copepods includes only six post-naupliar stages. The generation time from egg extrusion to adult for L. simplex was approximately 10 days at 22 °C. The body length of the ovigerous females ranged between 2.2 and 4.1 mm, and its fecundity between 12 and 36 eggs per string. Fecundity was negatively correlated with the egg size and positively correlated with the egg string length. Our data did not reveal significant differences in fecundity among sampling months, but ovigerous females were significantly larger in March (when water temperature was 22 °C) than in June and July (when water temperature was 30 °C). To some extent, our fecundity results contrast with those found in species of sea lice from higher latitudes. Undoubtedly, biological information on different species of sea lice from different environmental conditions will enhance our understanding of their infection strategies and will be valuable, given the increasing interest in marine fish farming in Mexico., Francisco Neptalí Morales-Serna, Ana Inés Rivas-Salas, Samuel Gómez, Emma Josefina Fajer-Ávila., and Obsahuje bibliografii
Based on light and electron microscopical studies, a new nematode parasite, Echinocephalus inserratus sp. n. (Spirurida: Gnathostomatidae), is described from the spiral valve of the broad cowtail stingray Pastinachus ater (Macleay) (Dasyatidae, Myliobatiformes) from off New Caledonia. The new species is morphologically and biometrically most similar to Echinocephalus overstreeti Deardorff et Ko, 1983, differing from it mainly in the absence of serrations on the posterior parts of pseudolabia and on interlabia, and in having a longer gubernaculum (150-299 µm long). Morphologically unidentifiable, mostly encapsulated larvae of Echinocephalus spp. were recorded from the following six species of teleost fishes collected in New Caledonian waters, serving as paratenic hosts: Perciformes: Acanthopagrus berda (Forsskål) (Sparidae) and Nemipterus furcosus (Valenciennes) (Nemipteridae); Tetraodontiformes: Abalistes stellatus (Anonymous), Pseudobalistes fuscus (Bloch et Schneider) (both Balistidae), Lagocephalus sceleratus (Gmelin) (Tetraodontidae) and Aluterus monoceros (Linnaeus) (Monacanthidae). Co-parasitising larvae of Ascarophis sp. and Hysterothylacium sp. were also collected from P. fuscus. All these findings represent new host and geographical records. A key to valid species of Echinocephalus Molin, 1858 is provided.
Problem. A lack of empathy toward victimized students belongs to the key factors that fuel longterm bullying cases. The absence of cognitive empathy toward victims is characterized by inability or unwillingness of classmates to understand the emotions and the situation of victimized students. It relates to moral disengagement processes, including dehumanizing disregard to the harm of the victims. Sample and methods. The study examined the association between victimization by bullying (assessed using self-reports) and cognitive empathy received from classmates (measured by peer nominations for students who do not feel well among others or others treat them unfairly) in seventh graders (n=190). Binary logistic regression was used to analyze the association when controlling for effects of peer status, gender, and sympathy of victimized students.Results. Students feel cognitive empathy for approximately half of the victims in their classrooms and cognitive empathy had a weak positive correlation with victimization frequency. Binary logistic regression showed that above-average cognitive empathy received from classmates is more likely in victims, students with low peer status, and male students. Because victimized students whose harm and difficult plight is overlooked by classmates have been considered victims most susceptible to psychological and social maladjustment, intervention efforts could benefit from tracing not only the established diagnostic criteria, but also cognitive empathy received from the side of classmates.Limitations. The findings may be limited by using a cross-sectional design and working with a convenience and relatively small sample (with a limited number of victims). and Problém. Jedním z klíčových prvků přispívajících k dlouhodobému trvání případů šikany je absence empatie k šikanovaným spolužákům. Absence kognitivní složky empatie se vyznačuje neschopností či neochotou spolužáků porozumět emocím a situaci šikanovaných žáků. Pojí se s procesy morálního vyvazování, včetně dehumanizace, při níž přestávají být spolužáci vnímaví k utrpení oběti. Důležitou otázkou je, jak velká část šikanovaných žáků získává empatii od svých spolužáků a zda tato empatie souvisí s charakteristikami šikanovaných žáků. Soubor a metoda. Studie zkoumala u žáků sedmých ročníků (n = 190) vztah mezi viktimizací (na základě sebeposouzení) a kognitivní empatií získanou od spolužáků (vrstevnickou nominací žáků, kteří se mezi ostatními necítí dobře či se k nim ostatní chovají nespravedlivě). Pomocí binární logistické regrese sledovala tento vztah při kontrole skupinového statusu, pohlaví a soucitu šikanovaného žáka. Výsledky. Spolužáci empatizují přibližně s polovinou obětí ve svých třídách. Frekvence viktimizace slabě pozitivně koreluje s mírou získané empatie od spolužáků. Podle výsledků binární logistické regrese predikuje nadprůměrnou míru empatie od spolužáků zkušenost s viktimizací a nízký skupinový status. Nadprůměrnou empatii spolužáků také častěji získávají chlapci. Vzhledem k tomu, že šikanované žáky, jejichž utrpení a obtížnou pozici spolužáci přehlížejí, lze považovat za nejohroženější oběti s potenciálními psychickými a sociálními následky, z intervenčního hlediska se jeví jako užitečné sledovat vedle existujících diagnostických kritérií i empatii spolužáků vůči konkrétním šikanovaným žákům. Limity. Výsledky studie mohou být omezeny příležitostným výběrem, nízkým počtem častěji šikanovaných žáků a průřezovým výzkumným designem.
A total of 52 specimens of the Pacific seabream Acanthopagrus pacificus Iwatsuki, Kume et Yoshino from the Gulf of Tonkin off Vietnam were examined for monogeneans. Twenty fish were parasitised by 101 individuals of five monogenean species, including two known species Allodiscocotyla diacanthi Unnithan, 1962 and Heterapta chorinemi (Tripathi, 1956), as well as three new species, Polylabroides tienyenensis sp. n., Polylabroides tonkinensis sp. n. and Metacamopia lebedevi sp. n. Polylabroides tienyenensis and P. tonkinensis are morphologically more similar to Polylabroides guangdongensis Zhang et Yang, 2001 in comparison with other species within the genus, based on the absence of small spines on the cirrus. However, P. tonkinensis is distinguished from P. guangdongensis by fewer clamps on the haptor and by the different shapes of the large spines on the cirrus. Similarly, P. tienyenensis differs from P. guangdongensis by vaginal ducts with fewer branches, fewer clamps and smaller egg size. Metacamopia lebedevi is distinguished from Metacamopia chorinemi (Yamaguti, 1953) by the arrangement of testes (one row vs two rows), diverticula absent in the oesophagus, and the number of anchor pairs (one vs two); it differs from Metacamopia oligoplites Takemoto, Amato et Luque, 1996 by the smaller haptor, shape and absence of small sclerotised hooks, the number of ribs in their clamps, and the position of the testes; it can be separated from Metacamopia indica (Unnithan, 1962) by having fewer testes and lacking sclerotised structures in the vagina. The present study also provides the measurements for A. diacanthi, H. chorinemi, and proposes a new key to all species of Polylabroides.
The mistle thrush is a species that occurs in old-growth forests, especially coniferous forests, in hilly and mountain areas and avoids warm and dry areas and human settlements. Despite this, in recent decades, the mistle thrush has colonised Apulia, southern Italy's lowlands and coasts, in rural and urban contexts. This study investigates the habitat selection of this species in central Apulia, in both the breeding season and winter, by carrying out 301 point counts and 264 linear transects. Data were collected to build a Species Distribution Model (SDM) for each season with the MaxEnt algorithm and the regional land use map, selecting variables through the Akaike Information Criterion. Overlap in the suitability of both seasons was measured using Schoener's D. A total of 133 observations of mistle thrush were noted during the breeding season and 85 observations during winter. During the breeding season, the mistle thrush selected olive orchards, especially those near vineyards and urban areas, where it could find food and safe places to nest. In this period, however, it was also found in coniferous woodlands. The mistle thrush also used vineyards in winter, whereas it avoided urban areas in this period, possibly due to food scarcity. Non-irrigated arable lands were avoided all year round, whereas natural grasslands were only avoided during the winter. Irrigated arable lands positively affected the species. Furthermore, 60% of habitat characteristics were similar between the breeding and winter seasons. It is unclear what makes the mistle thrush shift its range southward and downslope. However, it is likely due to the general increase in forest cover, a positive rainfall trend in Central Italy during summer, and the absence of competition with similar species in central Apulia.
The taxonomy of Diplectanum Diesing, 1858, a genus of monopisthocotylean monogeneans, remains unsettled and needs to be revised based on new morphological criteria. Recent studies in monopisthocotyleans have shown that the muscle arrangement in the posterior attachment organ (haptor) differs between congeneric species and can be used as an additional criterion in genus-level taxonomy. To explore the possibility of using the haptoral musculature and nervous system in the taxonomy of Diplectanum, we conducted a detailed confocal-microscopy study of three species of Diplectanum (D. aculeatum Parona et Perugia, 1889, D. sciaenae van Beneden et Hesse, 1863 and D. similis Bychowsky, 1957) with phalloidin staining for muscle and indirect immunostaining for 5HT and FMRFamide. A further goal was to clarify the functional mechanics of the haptor and the role of its essential components (squamodiscs and anchors) in attachment to the host. The system of connecting bars and gaffing anchors was found to have a complex musculature consisting of 23 muscles in D. aculeatum and D. sciaenae, and 21 muscles in D. similis. The squamodiscs were shown to be operated by several groups of muscles attached primarily to the area termed the squamodisc fulcrum. Most of the haptoral musculature is identical in D. aculeatum and D. sciaenae and these species differ only in the presence of a muscle sheath around the tissue strand between the squamodiscs in D. sciaenae and in the different patterns of superficial squamodisc muscles. Diplectanum similis shows more significant differences from the other two species: besides lacking two of the haptoral muscles, it also differs in the shapes and arrangement of several other muscles. The nervous system of all three species conforms to the general pattern typical for the Dactylogyroidea and shows little variation between species., Anatoly A. Petrov, Evgenija V. Dmitrieva, Maryana P. Popyuk, Pavel I. Gerasev, Sergey A. Petrov., and Obsahuje bibliografii
The viviparous gyrodactylid genus Macrogyrodactylus Malmberg, 1957 is endemic to Africa, composed of nine species from hosts of four freshwater fish families, including catfishes (Siluriformes: Clariidae). Three species, Macrogyrodactylus clarii Gussev, 1961; M. congolensis (Prudhoe, 1957) and M. karibae Douëllou et Chishawa, 1995, are primarily known to parasitise the African sharptooth catfish Clarias gariepinus (Burchell) in various African countries. From November 2017 to September 2019, a total of 184 individuals of C. gariepinus were collected from selected localities in southern Africa and their skin, fins and gills were surveyed for monogeneans. Three species of Macrogyrodactylus (M. clarii, M. congolensis and M. karibae) were found parasitising C. gariepinus from five localities in South Africa and Zambia. Overall prevalence was 50% to 100% with intensities of up to 109 parasites per host individual. New locality records in southern Africa, morphological observations and additional molecular data on the complete Internal Transcriber Spacer (ITS-1-5.8S-ITS-2) regions of the rDNA gene for the three gyrodactylid species are presented in this study.
Livestock depredation can be devastating to both farmers and the species considered responsible if they are subsequently persecuted. Many proposed conflict solutions are limited in their uptake because they may be short-term, localised, expensive or species-specific. Livestock guarding dogs have been a successful solution in many parts of the world, however recommended imported breeds are generally expensive or inaccessible to many rural farmers. In this study, we report on a program placing local Tswana dogs with farmers in Botswana as a tool to reduce livestock loss. Seventy-five farmers who experienced high conflict from carnivores in both rangelands and wildlife areas were selected to receive a Tswana puppy. Puppies were monitored regularly to determine their performance, survival and owner attitudes toward wildlife. From initial baseline reports of goat losses before farmers received a puppy, loss declined by at least 85% over the following three years. Farmers were very satisfied with the performance of their livestock guarding dog and attitudes toward protection and tolerance of wildlife improved after one year of receiving a puppy. Our study suggests locally bred Tswana dogs are an effective solution for livestock at risk to depredation, particularly for rural farmers and development of community-led programs can be further used to reduce conflict.
Parasites commonly manipulate host behaviour to increase transmission success between hosts. While most behavioural changes comprise slight alterations to host activity patterns and habitat use, some represent impressive alterations to routine behaviour which, while having direct positive effects on parasite transmission, compromise host survival. Here, we report conspicuous risky behaviour in an African annual killifish, Nothobranchius furzeri, infected by metacercariae of a strigeid trematode, Apatemon sp., residing in their cranial cavity. We demonstrate a striking contrast in the spatial and temporal behavioural responses of fish from populations naturally infected with Apatemon sp. and fish from two control populations with either a similar baseline parasite fauna but lacking Apatemon, or an overall low-level of infection. During routine activity, fish from Apatemon-infected populations positioned themselves just below the water surface, while other fish spent most of their time near the bottom. During a simulated avian attack, killifish from Apatemon-infected populations jumped above the water surface, moved in an uncoordinated manner, and rotated in the upper water layer, while fish from the control populations rapidly escaped into deeper water and ceased moving. The same self-exposing behaviour (jumping out of the water and lying on floating lily pads for extended periods) was also observed under natural conditions. Such behaviour greatly facilitates location of Apatemon-infected host fish by avian definitive hosts, especially in turbid pools. Moreover, the nothobranchiid killifish host's own life history, i.e. an extremely short lifespan limited to several months, may represent an important driver in the evolution of behavioural manipulation.