Contribution to the knowledge of the terrestrial isopod fauna of Lithuania

The present survey provides records on terrestrial isopods from southern and north-western parts of Lithuania. Isopods were sampled manually by checking substrates in eight habitats (several types of forest and anthropogenic environment) between 2014 and 2016. In total, seven species were recorded. The common European species Trachelipus rathkii was noted as the most frequent isopod in all studied habitats from southern Lithuania. Porcellionides pruinosus, found in the habitat of anthropogenic activity, was recorded for the first time from Lithuania. Based on the data of the present study and previous surveys, the 14 species of terrestrial isopods are recorded in Lithuania and the current state of knowledge about Lithuanian isopod is summarised.

Preliminary data on terrestrial isopods from some railways in Dobruja, eastern Romania

In July 2020 we analyzed the terrestrial isopod assemblages from different (mostly abandoned) railway constructions in Dobruja, eastern Romania. We identified 10 terrestrial isopod species, of which the most abundant and frequent were Porcellionides pruinosus (Brandt, 1833) and Armadillidium vulgare Latreille, 1804. We identified species that, in Romania, are present only in Dobruja: Leptotrichus pilosus Dollfus, 1905 and Trachelipus squamuliger (Verhoeff, 1907). Most of the species are common, generalist or synanthropic, connected to dry and open habitats. In abandoned railway-stations the number of species/samples was low (at most two), but at the base of a stone railway bridge in Babadag forest six species were found.

Structure of a hinge joint with textured sliding surfaces in terrestrial isopods (Crustacea: Isopoda: Oniscidea)

Background The study of joints in terrestrial arthropods can provide insights into the evolutionary optimization of contacting surfaces that slide without lubrication. This work reports on the structure of the joint between the propodus and the dactylus in terrestrial isopods, the most successful group of crustaceans on land, focusing on the woodlouse Porcellio scaber. Methods The joints were studied using fluorescence microscopy, 3D reconstruction, scanning electron microscopy and transmission electron microscopy. The obtained results were functionally interpreted using high-speed video recordings by analyzing the use of the joint during locomotion. Results In the joint, which allows the dactylus to move in a single plain, a semicircular process on the propodus fits into a groove on the dactylus and guides its movement. The sliding surfaces of the propodal process are textured in the form of parallel epicuticular ridges a few hundred nanometers thick. This texturing is selective: while the less heavily loaded surfaces are textured, the surfaces that support the isopod during standing and walking are smooth. In contrast, the groove on the dactylus is completely smooth. We found a similar surface texture in several other species of terrestrial isopods and one aquatic isopod. Conclusions The selective texturing of the joint may reduce wear by eliminating small particles. This effect of the ridges was confirmed using electron microscopy. The absence of ridges on heavily loaded surfaces may enhance the dissipation of forces in these regions.

Liver Cysts in a Kitten with Platynosomum sp.

Background: Hepatic cysts are rarely described in association with infections by Platynosomum sp. Infected animals are most often asymptomatic, and the severity of symptoms is associated with the number of biliary tract parasites, which may lead to cholangitis and cholangiohepatitis. Although platinosomiasis is often associated with cholangitis and cholangiohepatitis, it rarely is with polycystic disease. For the parasite’s life cycle to occur, the infected cat must eliminate the eggs in the feces and three intermediate hosts are needed: snails, terrestrial isopods and vertebrates like the frog or the gecko. The eggs are ingested by the snails, then the miracids are released and matured into the mother sporocyst form, which originates child sporocysts containing the cercariae, that leave the mollusks for the soil and are ingested by the terrestrial isopod in which the cercariae matures until metacercariae. Vertebrates ingest terrestrial isopods and are ingested by felines. The present study aimed to report an unusual case of platinosomiasis with the development of multiple hepatic cysts.Case: A mixed breed male kitten was admitted with a history of apathy, hyporexia, increased abdominal volume and jaundice. In the ultrasound examination, we could see hepatomegaly and several hypoecogenic rounded structures, similar to cysts. There was an increase of serum concentration of the hepatic enzymes alanine transaminase and gamma glutamyl transferase enzyme. The parasite’s eggs were investigated in the patient’s feces using the simple sedimentation method, with a negative result. The animal was submitted to celiotomy and it was possible to observe several cystic structures in the liver. The cysts content was sent to cytology and culture. Cytology result was compatible with liver cyst and there was no bacterial growth in the culture. Bile fluid was collected and sent for Platynosomum sp. research using the centrifugal sedimentation test in formalin-ether solution, which allowed the parasite’s eggs to be observed. The cat was treated with praziquantel,silymarin, S-Adenosyl methionine, and ursodeoxycholic acid. The patient gradually improved from jaundice and there was a reduction in abdominal volume. Discussion: This report describes a case of platinossomiasis associated with polycystic liver disease in a domestic cat, which seems to be an uncommon presentation. Most infected cats are asymptomatic, but some animals may exhibit anorexia, apathy, increased abdominal volume due to hepatomegaly and/or ascitis and jaundice. Although infestation in domestic cats is relatively common, its association with liver cysts is rare or poorly reported in the literature, representing a diagnostic challenge, which makes mandatory the inclusion of this differential diagnosis in polycystic liver diseases in cats. The diagnosis of this parasitosis can be made based on the association among clinical signs, laboratory tests and ultrasound examination, but the definitive diagnosis is usually made by visualizing the parasite’s eggs. In the case described, it was not possible to observe parasite’s eggs in the patient’s feces, but in the bile. Platynosomum sp. infection should always be considered as a differential diagnosis in cases of polycystic liver disease in cats, especially in countries with tropical or subtropical climate. Early diagnosis and appropriate treatment were fundamental for the improvement of the patient’s clinical condition.Keywords: feline, liver, platinosomiasis, polycystic disease, jaundice, cystic lesions.