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Two new species of the genus Dugesia (Platyhelminthes, Tricladida, Dugesiidae) from the tropical monsoon forest in southern China are described on the basis of an integrative taxonomic study involving morphology, karyology, histology, and molecular analyses. The new species Dugesia circumcisa Chen & Dong, sp. nov. is characterised by asymmetrical openings of the oviducts; right vas deferens opening at anterior portion of the seminal vesicle and the left one opening at mid-lateral portion of the seminal vesicle; two diaphragms in ejaculatory duct, the latter being ventrally displaced and opening at the tip of the penis papilla, which is provided with a nozzle; wide duct connecting male atrium and common atrium; chromosome complement triploid with 24 metacentric chromosomes. The other new species, Dugesia verrucula Chen & Dong, sp. nov., is characterised by the large size of the living worm, usually exceeding 3.5 cm in length; asymmetrical openings of the oviducts; subterminal opening of ventrally displaced ejaculatory duct; vasa deferentia symmetrically opening into the postero-lateral portion of the seminal vesicle; well-developed duct between the seminal vesicle and diaphragm; single dorsal bump near the root of the penis papilla; bursal canal with pleated wall and spacious posterior section; unstalked cocoons; chromosome complement diploid with 16 metacentric chromosomes. Inter-specific molecular distances and their positions in the phylogenetic tree reveal that D. circumcisa and D. verrucula are clearly separated from their congeners.

Two new species of the genus Dugesia (Platyhelminthes, Tricladida, Dugesiidae) from Hainan Island of China are described on the basis of morphological, karyological and molecular data. Dugesia semiglobosa Chen & Dong, sp. nov. is mainly characterized by a hemispherical, asymmetrical penis papilla with ventrally displaced ejaculatory duct opening terminally at tip of penis papilla; vasa deferentia separately opening into mid-dorsal portion of intrabulbar seminal vesicle; two diaphragms in the ejaculatory duct; copulatory bursa formed by expansion of bursal canal, lined with complex stratified epithelium, which projects through opening in bursa towards intestine, without having open communication with the gut; mixoploid chromosome complement diploid (2n = 16) and triploid (3n = 24), with metacentric chromosomes. Dugesia majuscula Chen & Dong, sp. nov. is mainly characterized by oviducts opening asymmetrically into female reproductive system; hyperplasic ovaries; expanded posterior section of bursal canal; vasa deferentia separately opening into mid-dorsal portion of seminal vesicle; asymmetrical penis papilla due to ventral course of ejaculatory duct, which has subterminal and dorsal opening at tip papilla; mixoploid chromosome complement diploid (2n = 16) and triploid (3n = 24); chromosomes metacentric. Apart from their anatomy, separate species status of the two new species is supported also by their genetic distances and by their positions in the phylogenetic tree. The sexualization process may have been induced by the lower temperatures, in comparison with their natural habitat, under which the worms were cultured in the laboratory.

Living representatives of the Neotropical genus Choeradoplana Graff, 1896 ( Geoplaninae , Tricladida , Platyhelminthes ) are easily recognized by the typical shape of the head which is laterally expanded, rolled-up, and ventrally provided with two glandular cushions. In this study, the morphology and phylogeny (cytochrome C oxidase subunit I gene) of several species of land planarians are taxonomically investigated. Four of the six species studied are new to science, namely: Ch. eudoxiae Silva & Carbayo, sp. nov., Ch. claudioi Lago-Barcia & Carbayo, sp. nov., Ch. onae Lago-Barcia & Carbayo, sp. nov., and Ch. riutortae Lago-Barcia & Carbayo, sp. nov. The species Choeradoplana albonigra and Ch. eudoxiae deviate from the usual body shape pattern in that the head does not present lateral expansions nor glandular cushions, becoming indistinguishable from its sister genus Cephaloflexa . Pseudogeoplana tristriata (Schultze & Muller, 1857) is also redescribed from a newly collected specimen and was discovered to be a member of Choeradoplana . Graff (1899) also studied another specimen that was considered to be conspecific with P. tristriata ; however, in this new it is concluded that it is not conspecific but rather a new species. The name Pseudogeoplana aevipandemiae Lago-Barcia & Carbayo, sp. nov. is suggested for Graff’s specimen.

By means of an integrated approach, including molecular, morphological, anatomical and histological data, we describe a new species of freshwater flatworm of the genus Dugesia from southwest China, representing the third species recorded for the country. Morphologically, the new species, Dugesia umbonata Song & Wang, sp. nov., is particularly characterised by the presence of a muscularised hump immediately antero-dorsally to a knee-shaped bend in its bursal canal and by an ejaculatory duct that opens subterminally through the dorsal side of the penis papilla. Four molecular datasets (18S rDNA; ITS-1; 28S rDNA; COI) facilitated determination of the phylogenetic position of the new species, which belongs to a clade comprising other species from the Australasian and Oriental regions. We also analysed the structure of its major nervous system by means of the acetylcholinesterase (AChE) histochemical method and compared these results with data available for three other species of Dugesia.

The genus Choeradoplana Graff, 1896 encompasses 16 species, most of them found in Brazil. Herein two new species of this genus are described from remnants of Araucaria moist forests, located in the states of Paraná and Santa Catarina, south Brazil. Both species resemble the type-species of the genus, C.iheringi, showing brownish dorsal surface covered by dark-brown flecks. However, regarding their anatomy, the new species differ from C.iheringi and other congeners by a long and horizontal disposed permanent papilla. In such aspects, both species resemble C.benyai, but differ from this species, as well as from each other, in details of the prostatic vesicle, ejaculatory duct, and penis papilla.

The blue land planarian Caenoplana coerulea Moseley, 1877 is reported for the first time in the hypogean environment. Seven individuals of C. coerulea were collected in the most humid branch of an abandoned water mine in Gran Canaria (Canary Islands). Due to its character of generalist predator, it should be considered a threat for the endemic subterranean fauna.

In a fauna survey in the eastern margin of Serra do Espinhaço Plateau, in an area belonging to the Brazilian savanna (Cerrado phytophysiognomy), a land flatworm was sampled in a ferruginous cave. Anatomical and histological analyses indicated that it belongs to a new species of the genusPasipha, which is herein described. The new species shows an almost homogenous dark brown dorsal pigmentation, eyes spreading over the dorsal surface, a collar-shaped pharynx, and a prostatic vesicle with two portions separated by a canal. It differs from similar species mainly by anatomical and histological details of the ejaculatory duct, as well as male and female atria. The flatworm shows no troglomorphic traits and was collected once in the entrance zone of the cave. Hence, despite representing the first land flatworm species described from a Neotropical cave, we consider that its occurrence in the cave is probably occasional, using it as a shelter.

The New Guinea flatworm (Platydemus manokwari) caused extinction of the native land snails on several Pacific island in past decades, and therefore it has been listed among the top 100 of the world’s worst invasive alien species. Using morphological and molecular methods, New Guinea flatworms were discovered and identified for the first time in Hong Kong Island during a field investigation in July and August 2018. The flatworms were 32–60 mm long, 3–5 mm wide, and 1–2 mm thick. The dorsal side of the flatworm was dark brown with a thin yellow central line, and its ventral side appeared pale grey. To further verify this species, both 18S rDNA and mitochondrial cytochrome c oxidase subunit I gene (COX1) obtained from three specimens of P. manokwari were sequenced and analysed. While comparing these sequences with those previously deposited in GenBank, these 18S rDNA sequences shared 100% identity with the single available 18S rDNA sequence of P. manokwari; and the obtained COX1 sequences were identical to those of P. manokwari world genotype. Two native snails, Criptosoma imperator and Bradybaena similaris, have been found to be the prey of this predator during this investigation. Therefore, the invasive New Guinea flatworm certainly will cause a serious impact on the biodiversity of native snail populations, and an economic and environmental risk assessment for P. manokwari need to be completed in the near future in Hong Kong.

In 2016, the type-material of ten of the 15 Brazilian land planarians (Platyhelminthes, Tricladida, Geoplanidae) described by Schirch (1929) was discovered deposited in the Museu Nacional do Rio de Janeiro (MNRJ). Schirch only described the external morphology of these species, all originally placed in the genus Geoplana. By the 1930s and 1950s Geoplana itatiayana, G. plana, and G. rezendei underwent taxonomic revision based on the study of non-type specimens. The remaining 12 species also underwent a taxonomic revision but only based on the literature. Current names of these species are Geoplana goettei, Pseudogeoplana arpi, Ps. blaseri, Ps. bonita, Ps. bresslaui, Ps. cardosi, Ps. doederleini, Ps. lumbricoides, Ps. obscura, Ps. riedeli, Ps. theresopolitana, and Ps. wetzeli. The species Geoplana maximiliani sensu Schirch (1929) was renamed as Ps. schirchi Ogren & Kawakatsu, 1990. The present study reports a taxonomic revision of seven of Schirch’s species using type material, namely Obama itatiayana, Pasipha plana, Pseudogeoplana arpi, Ps. bresslaui, Ps. doederleini, Ps. schirchi and Ps. wetzeli. Additional specimens of some of these species were also examined. Morphological data from histological preparations and from virtual sections were obtained through a non-destructive technique of X-ray computed microtomography (µCT). This approach resulted in the preservation of the entire body of at least one type-specimen of each species, and the holotype of Ps. bresslaui. Conspecificity of O. itatiayana and P. plana was confirmed, as previously reported in the literature. It is also proposed that Ps. bresslaui belongs to the genus Paraba, while the other species should remain in Pseudogeoplana, since type-specimens are either immature, poorly preserved or simply lost.

Las especies invasoras pueden causar diversos problemas a nivel socioeconómico y para la conservación de la biodiversidad. La detección temprana de las especies naturalizadas puede ser de vital importancia para el monitoreo y la planificación de estrategias de contención del proceso de invasión. La fauna de planarias terrestres (Tricladida, Geoplanoidea), babosas terrestres (Mollusca, Limacidae), diplópodos (Myriapoda, Diplopoda) y sínfilos (Myriapoda, Symphyla) de la Ciudad Autónoma de Buenos Aires se encuentra poco estudiada, y la adición de especies exóticas transportadas por las actividades humanas complejiza la situación de poco conocimiento. En este trabajo se dan a conocer nuevos registros de especies de estos grupos que se han naturalizado en el ámbito urbano de la ciudad y sus alrededores (Bipalium kewense, Austroplana sanguinea, Ambigolimax valentianus, Brachyiulus pusillus, Oxidus gracilis y Scutigerella immaculata). Se evaluó el potencial como invasor de cada especie en base a lo registrado en otros países. Hasta el día de la fecha no existen registros publicados de planarias terrestres, sínfilos, o diplópodos para esta área, por lo cual el presente trabajo constituye la primera contribución sobre estos grupos. Las especies mencionadas perjudican a las actividades agropecuarias y horticulturales de diversas formas. Una tarea a futuro deberá ser la cuantificación de los daños que causan para establecer su importancia y el costo/beneficio de su control o manejo., Exotic invertebrates in the city of Buenos Aires. First steps for the monitoring of potential biological invasions. Invasive species can cause several problems at the socio-economic level and for the biodiversity conservation. The early detection of naturalized species can be of vital importance for the planning of containment strategies of the invasion process. The flat worms (Tricladida, Geoplanoidea), land slugs (Mollusca, Limacidae), millipedes (Myriapoda, Diplopoda) and symphillids (Myriapoda, Symphylla) of the Ciudad Autonoma de Buenos Aires it is little studied, and the addition of exotic species transported by human activities complicates the situation of little knowledge. In this work, we present new records of species of these groups that have become naturalized in the urban area of the city and its surroundings (Bipalium kewense, Austroplana sanguinea, Ambigolimax valentianus, Brachyiulus pusillus, Oxidus gracilis y Scutigerella immaculata). The invasive potential of each species was evaluated based on what was registered in other countries. Until the date there are no published records of terrestrial flat worms, symphillids, or millipedes for this area, for which the present work constitutes the first contribution on these groups. The aforementioned species damage agricultural and horticultural activities in different ways. A future task should be the quantification of the damage caused to establish its importance and the cost / benefit of its control or management., Facultad de Ciencias Naturales y Museo

Planarians, the representatives of an ancient bilaterian group with complex reproductive system and high regenerative capabilities, are model system suitable for studying the basic molecular requirements for the development of the reproductive system. To further explore the morphological changes of the gonads during desexualization and the molecular events of the genes controlling the reproductive system development in planarians, we have investigated the histological changes of ovary and testis by paraffin section and the expression patterns of reproductive-related genes by the quantitative real-time PCR in Dugesiajaponica Ichikawa & Kawakatsu, 1964, upon starvation. The four genes, Djprps, DjvlgA, DjvlgB and Djnos, have been selected. The research results show that the degradation of ovary changes from outside layer to inside, and the testis changes are opposite; the reproductive capacity of the planarians starts to be damaged from the 17th to 25th days and to disappear completely from the 26th to 37th days during starvation. The expression patterns of the four genes exhibit the obvious dynamic variations during their desexualization, which indicates that these genes might be involved in gonad development.