Francisco Brusa

• Museo de La Plata at National University of La Plata

La obra contiene ocho capítulos que siguen el programa vigente de la materia Introducción a la Taxonomía de la Facultad de Ciencias Naturales y Museo. El material organiza y presenta las temáticas y ejercicios que se abordan a lo largo del curso. Cada capítulo consiste en una selección de ejercicios prácticos acompañados de una breve introducción t...

The dataset of free-living soil nematodes from Colección Helmintológica of Museo de La Plata is presented. There is a large knowledge gap regarding soil nematodes especially in Argentina but also in the Neotropical region and this dataset provides information on this topic. The collection includes more than 850 specimens, organized in 294 lots of n...

La obra contiene ocho capítulos que siguen el programa vigente de la materia Introducción a la Taxonomía de la Facultad de Ciencias Naturales y Museo (UNLP). El material organiza y presenta las temáticas y ejercicios que se abordan a lo largo del curso. Cada capítulo consiste en una selección de ejercicios prácticos acompañados de una breve introdu...

The marine microturbellarian diversity is scarcely known from the Pacific coastline of South America. The coastal margin of Peru is highly influenced by cold-water currents (Humboldt Current System). These cold-water currents play important roles in shaping the marine species diversity in this area. However, there are no previous records of marine...

Notogynaphallia urku sp. nov. is here described from the north-east region of Peru, in the Amazonian lowlands. Specimens of the new species are flattened, up to 120 mm long, and characterised by their dorsal colouration consisting of a median band of melon yellow, on which run two irregular longitudinal stripes formed by tiny jet black dots; cephal...

Microturbellarians are all mostly small free-living Platyhelminthes that do not belong to either the Polycladida or Tricladida order. This group includes species of the clades Catenulida and Rhabditophora. Species of microturbellarians are known to live in marine and continental waters such as rivers, where they are diverse and abundant. However, t...

The morphological and molecular (mitochondrial cytochrome c oxidase subunit I, COI) characterization of a new species of the subfamily Geoplaninae (Geoplanidae) supports the erection of a new genus, Anophthalmoplana gen. nov. The most remarkable feature of Anophthalmoplana horticola sp. nov. is the absence of eyes, a feature so far only recorded in...

Abstract Free-living turbellarians mostly live in marine and freshwater environments, but they have been little considered in ecological studies. The coastal plain in southern Brazil harbors a diverse fauna and flora, but only a few studies have related environmental factors to the abundance, richness, and distribution of turbellarians. Hence, we a...

The Taim strict nature reserve (ESEC Taim) is a protected wetland (Ramsar site) in southern Brazil. Although the ESEC Taim harbours a broad conspicuous flora and fauna, this area lacks studies on free-living Platyhelminthes. Here, we describe three new species to science, one belonging to Macrostomorpha (Macrostomum itai n. sp.) and two belonging t...

Los Turbelarios, Platyhelminthes de vida libre (generalmente), pertenecen a dos grupos Catenulida y Rhabditophora. Los Turbelarios presentan variedad de configuraciones y tamaños corporales: cuerpo ciliado y aplanado (vermiformes), y son hermafroditas simultáneos con fertilización cruzada. Estos animales viven en ambientes marinos, salobres, dulcea...

Girardia Ball, 1974 is the most diverse and widely distributed genus of the family Dugesiidae (Platyhelminthes: Continenticola) in the Neotropical region. Seven out of the 52 species of the genus are known for Argentina. The Somuncurá Plateau is a region in northern Patagonia with several endemic flora and fauna, but little is known about the free-...

Polyclads are marine free-living Platyhelminthes, generally disregarded in marine environmental assessments. Here, Phrikoceros inca (Cotylea, Pseudocerotidae), identified on the basis of external features such as its ear-like, held-erected pseudotentacles, number and position of pseudotentacular eyes, circular-like cerebral eyespot, ruffled-shaped...

Our knowledge about the diversity of land planarians (Platyhelminthes: Geoplanidae) from the Andean‐Patagonian Forests is scarce compared with other forested biomes. These cold‐temperate forests are located in southern Chile and western Patagonia in Argentina, at the southern end of South America. Many species of land planarians from this region ar...

Catenulida are mostly inhabitants of freshwater ecosystems, like ponds, streams, though the marine species are few (Larsson and Willems, 2010). About 110 species of catenulids are known worldwide, with most of the studies conducted in South America (Marcus, 1945a, 1945b; Noreña et al., 2005), North America (Kepner and Carter 1931; Nuttycombe and Wa...

Turbellarians are mostly free-living platyhelminthes living in different types of freshwater environments. An updated taxonomic review of Platyhelminthes from the Neotropical and Antarctic region is presented in this chapter. Dichotomous identification keys to the lowest justifiable taxonomic level based on the most recent literature are provided....

Land flatworms usually show low ability to disperse and high endemicity, displaying many singletons in studies on land planarian assemblages. Thus, many species have been described based on specimens sampled in a single locality and/or on a few specimens. Based on phylogenetic analyses of concatenated COI and 18S rRNA genes and morphological analys...

Obama nungara Carbayo, Álvarez‐Presas, Jones, & Riutort, 2016 is a land planarian (Platyhelminthes: Geoplanidae) native to southern South America, which has recently dispersed towards several countries of the European continent, thus becoming a threat to the native soil fauna. Its dispersion would be favoured by its wide food habit and its tendency...

Within the Platyhelminthes, Temnocephalida is a clade of continental turbellarians that establish an ectocommensal relationship with their hosts. Many species live associated with decapod crustaceans. In the Neotropical region, two species of Temnocephala are commensals on species of the shrimp family Palaemonidae. Temnocephala digitata lives on Pa...

Land flatworms usually show low ability to disperse and high endemicity, displaying many singletons in studies on land planarian assemblages. Thus, many species have been described based on specimens sampled in a single locality and/or on a few specimens. Based on phylogenetic analyses of concatenated COI and 18S rRNA genes and morphological analys...

Here, we describe two new flatworm species of the genera Obama Carbayo et al., 2013 and Notogynaphallia Ogren & Kawakatsu, 1990 (Geoplaninae) found in riverine forests of central-eastern Argentina. Obama maculatentis sp. nov., which is about 50 mm in length, is characterized by black olive pigmentation on the dorsum, with two irregular rows of blac...

Among other factors, globalization has promoted the spread of alien organisms, posing a great risk to Earth’s biodiversity. Land planarians of the family Geoplanidae especially benefit from human-mediated transport. Many species become established in new areas, where they represent threats to the native soil fauna. Obama nungara is a species descri...

Urastoma cyprinae (Platyhelminthes: Urastomidae) was collected among the gill filaments of cultured mussel Perna perna from three localities of Santa Catarina state in the south of Brazil. Samples of P. perna were taken monthly during July 2010 to June 2011. The diagnostic of U. cyprinae in P. perna showed to be more efficient by stereoscopic micro...

The genital system is the most thoroughly studied morphological feature in the genus Macrostomum (Platyhelminthes, Macrostomorpha) understanding different mating strategies. In the present study the musculature of the genital system of the freshwater flatworm Macrostomum johni was visualized using phalloidin-linked fluorescent dye by confocal laser...

The biology of Neotropical freshwater planarians (Platyhelminthes) is almost unknown compared with that of their Holarctic relatives. In this paper, we 1) studied the sequence of development of the reproductive system of Girardia capacivasa Sluys & Kawakatsu, 2005 (Dugesiidae), to estimate the onset of sexual maturity, applying the logistic regress...

Los turbelarios son los organismos bilaterales más sencillos que se conocen, difieren principalmente de grupos parásitos de platelmintos ya que mantienen una epidermis ciliada durante todo su ciclo de vida. A la fecha existen 6500 especies de turbelarios en el mundo; sin embargo, en Perú, catalogado como un país megadiverso, los estudios sobre la f...

El Perú posee uno de los mares con mayor diversidad del mundo; no obstante, el estudio de los invertebrados basales no se ha tomado en cuenta. Los turbelarios, organismos bilaterales basales, se pueden agrupar, según la longitud de sus cuerpos, como macroturbelarios (>1 cm) y microturbelarios (<~3 mm). Estos últimos son desconocidos en Perú. En est...

Species of Macrostomum are present in almost all regions of the world. These flatworms occur in different kinds of environments, from freshwater to marine ecosystems. Although Peru is considered one of the megadiverse countries in South America, little is known about freshwater microturbellarians in this country. Here we report the presence of M. r...

Here, we describe two new species of land planarians of the genera Pasipha and Imbira from the Atlantic Forest of Argentina: Pasipha quirogai sp. nov. and Imbira negrita sp. nov. Their external features and internal anatomy distinguish them from their congeners. Pasipha quirogai sp. nov. is about 40mm long, characterized by brown beige dorsal pigme...

Microturbellarians occur in a wide range of ecosystems, but their diversity and distribution are largely unknown. In this work, we report on the morphology, abundance, and distribution of 6 species of microturbellarians, namely Baicalellia evelinae, Catenula evelinae, C. leuca, C. turgida, Gieysztoria chiqchi, and Stenostomum hemisphericum. We prov...

This contribution summarizes knowledge of organisms associated with apple snails, mainly Pomacea spp., either in a facultative or obligate manner, paying special attention to diseases transmitted via these snails to humans. A wide spectrum of epibionts on the shell and operculum of snails are discussed. Among them algae, ciliates, rotifers, nematod...

A phylogenetic analysis of Polycladida based on two partial mitochondrial genes (cox1 and 16S) is provided. The analysis includes 30 polyclad terminals that represent species from the two taxa which traditionally divide the groups Cotylea and Acotylea. Our phylogenetic analyses pro- duced a well-supported hypothesis that confirms the mono- phyly of...

Los Turbelarios simbiontes han desarrollado una variedad de estrategias nutricionales y respiratorias que son ejemplo de las vías que pueden haber seguido los primeros Neodermata" ADAPTADO DE JOSEPH B. JENNINGS (1997) Entre los Platyhelminthes, los turbelarios son tradicionalmente reconocidos como la clase que agrupa a los representantes de vida li...

Desde su descubrimiento han constituido un rompecabezas taxonómico". LIBBIE H. HYMAN, THE INVERTEBRATES (1940) El phylum Dicyemida tradicionalmente se asociaba a los ortonéctidos, que parasitan varios grupos de in-vertebrados marinos (" turbelarios " , nemertinos, poliquetos, moluscos gasterópodos y bivalvos, ofiuros y ascidias), y se los incluía e...

In this paper we described two new species of Syndesmis living in Pseudechinus magellanicus in the Southwest Atlantic. The new species have a long stylet in the male reproductive system different to the known species of the genus. Syndesmis selknami n. sp, have a stylet of ∼220 μm length (1/3 of the body length). This ratio is unique because only f...

Los microturbelarios (Platyhelminthes) son invertebrados de vida libre dorsoventralmente aplanados, de tamaño reducido (1 – 1.5 mm) y habitan ambientes marinos, dulceacuícolas y salobres; suelen vivir en las raíces de la vegetación acuática o en el sedimento (comunidad del bentos). Los humedales costeros y ríos representan hábitats ideales para los...

The second volume in this landmark series includes an introductory chapter followed by 15 taxonomically specific chapters with identification keys to Nearctic freshwater invertebrates (protozoa through arthropods). Other than the second chapter’s treatment of the diverse, multi-phyla array of protozoa (ciliates, flagellates, and amoebas), each of t...

Temnocephalida, a group of small epibiontic worms strictly associated with freshwater hosts, includes 179 taxa in 23 genera, classified in two major groups: Scutarielloidea, distributed in the Palaearctic region, and Temnocephaloidea distributed mainly in the Australian and Neotropical regions. Based on a large-scale spatio-temporal dimension, a bi...

Previous studies demonstrated complex architecture of the muscular system of Macrostomum species, especially in the rostrum area and the pharynx. However, little is known about the differences in muscular pattern between species of the genus. This study examines and compares the muscular systems of specimens belonging to three freshwater Macrostomu...

A new species of land planarians of the genus Cratera is described. Cratera viridimaculata sp. n. was recorded in the Atlantic Forest Ecoregion, in north-eastern Argentina, and represents the first report of the genus Cratera outside Brazil. The new species is about 50 mm in length and externally characterized by a color pattern consisting of a lig...

The genus Pasipha Ogren & Kawakatsu, 1990 currently includes 22 species, most of them recorded in the Brazilian Atlantic Forest. Recently, Pasipha hauseri was documented in north-eastern Argentina, thus extending its distribution range. This paper reports new records of the genus Pasipha in the Interior Atlantic Forest ecoregion in Argentina, with...

The turbellarians are a key group due to the position they occupy in the tree of life, due to their regenerative capacities and other characteristics such as their cosmopolitanism, ubiquity, adaptability and their predatory role in food chains. "Turbellaria" has traditionally been considered a class, consisting of a group of heterogeneous orders, w...

The subfamily Geoplaninae (Geoplanidae) includes land planarian species of the Neotropical Region. In Argentina, the knowledge about land planarian diversity is still incipient, although this has recently increased mainly in the Atlantic Forest ecosystem. However, other regions like Chacoan forests remain virtually unexplored. In this paper, we des...

We report for the first time the occurrence of Obama marmorata in the Iberian Peninsula as an introduced species from the Neotropical Region. The species is also reported for the first time in Argentina. The identification was made on the basis of morphological evidence. The divergence levels of a fragment of the mitochondrial cytochrome c oxidase...

Based on published records and original data derived from our research, we have generated a checklist of symbiotic temnocephalan fauna from 57 taxa of freshwater invertebrate and vertebrate hosts from 16 families included in four classes from the Neotropics. The checklist contains 38 nominal species from 3 genera belonging to the Temnocephalida fam...

Los estudios en biodiversidad se enfocan a organis-mos conspicuos, e ignoran la vasta diversidad de es-pecies y la relevancia ecológica de muchos animales aparentemente poco importantes, como es el caso de los platelmintos, un grupo diverso de gusanos planos que habita ambientes acuáticos (marinos, salobres y dulceacuícolas) y terrestres. 1 Existen...

Supramontana argentina sp. nov. (Platyhelminthes, Continenticola, Geoplanidae) from north-eastern Argentina is herein described. The new species differs from Supramontana irritata Carbayo & Leal-Zanchet, 2003 from Brazil, the only species of this genus so far described, by external and internal morphological characters. Supramontana argentina sp. n...

Land planarians are an interesting group of free-living flatworms that can be useful as bioindicators because of their high sensitivity to environmental changes and low dispersal capacity. In this study, we describe and compare assemblages of land planarians from areas with different conservation degrees of the Interior Atlantic Forest (Misiones, A...

La Taxonomía, entendida como la teoría y práctica de la clasificación de los seres vivos, da sustento y nutre muchas otras ramas de la Biología. La práctica de esta disciplina, en su forma moderna, se remonta a mediados del siglo XVIII cuando se incorporó el concepto de Systema, para referirse al ordenamiento de los seres vivos, y la nomenclatura b...

We describe a new genus and a new species of Polycladida, Namyhplana henriettae (Platyhelminthes, Euplanidae), which lives associated with the tubes of the bivalve Bankia martensi in the fjords of the South Pacific Ocean in Chile. This species is characterized by a ribbon-like body, light brown colour, anterior region devoid of pigment, few eyes, n...

We revise the Neotropical distribution of Girardia festae (Platyhelminthes, Dugesiidae) following a new record in a Colombian high-altitude lake. G. festae is a freshwater planarian known mainly in the Andean Cordillera from Venezuela to Argentina. The species' key reproductive features include: ventral testes, bottle-like penis papilla, and sperm...

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Geoplana excelentissima sp. nov. is described from the east centre of Peru. This new species is very long (165 mm), broad and flat. The dorsal surface is black with five white stripes, and two marginal pinkish stripes with a blue inner surface. A unique combination of external and internal characters (e. g. the copulatory apparatus) is present in t...

This study reports Peruvian freshwater species of Stenostomum (Catenulida) from the upper Yurúa River of the Amazon Basin. A total of 11 species were found. One of them, Stenostomum ashanika, sp. nov., is described. It can be distinguished by: a pre-pharyngeal constriction; a small cauda; a small, rounded, mobile and ventrally directed pharynx; and...

During a histopathological survey of the geoduck, Panopea abbreviata (Hiatellidae), and the razor clam, Ensis macha (Pharidae), in northern Patagonian gulfs (Argentina), turbellarian worms were found in the intestine lumen. In this work, we described a new species of Paravortex (Platyhelminthes, Graffillidae). We collected the hosts by scuba diving...

94 Summary During a histopathological survey of the geoduck, Pano-pea abbreviata (Hiatellidae), and the razor clam, Ensis macha (Pharidae), in northern Patagonian gulfs (Argen-tina), turbellarian worms were found in the intestine lu-men. In this work, we described a new species of Para-vortex (Platyhelminthes, Graffillidae). We collected the hosts...

The blue land planarian Caenoplana coerulea is reported from Argentina (Buenos Aires province). We found C. coerulea in the east central region of Argentina in anthropic environments. The specimens that we found have the characteristic of the species found in others regions; that is, a bluish dorsal surface with a yellow mid-dorsal stripe and eyes...

The blue land planarian Caenoplana coerulea is reported from Argentina (Buenos Aires province). We found C. coerulea in the east central region of Argentina in anthropic environments. The specimens that we found have the characteristic of the species found in others regions; that is, a bluish dorsal surface with a yellow mid–dorsal stripe and eyes...

A new species of Geoplaninae land planarian from south Peru, Gigantea urubambensis sp. nov., is described. The most outstanding features of the new species are the very dorsal location of the testes, between the dorsal diagonal and the supra-intestinal parenchymatic muscle layers; a penis papilla projecting from the roof of the male atrium and acen...

A new species of Geoplaninae land planarian from south Peru, Gigantea urubambensis sp. nov., is described. The most outstanding features of the new species are the very dorsal location of the testes, between the dorsal diagonal and the supra-intestinal parenchymatic muscle layers; a penis papilla projecting from the roof of the male atrium and acen...

Negrete, Lisandro H. L., Brusa, Francisco, Carbayo, Fernando (2010): A new Peruvian land planarian species of the genus Gigantea (Platyhelminthes, Tricladida, Geoplanidae). Zootaxa 2422: 43-52, DOI: 10.5281/zenodo.194512

In this work we record two species belonging to the polyclad family Pseudocerotidae from the littoral zone of the Península Valdés (Patagonia, Argentina). This is the first record of members of Cotylea and the third of Polycladida from Argentina. The two new records are Phrikoceros mopsus, a species described for Brazil and Colombia and Thysanozoon...

We conducted a field survey for flatworms to select species as potential biological control agents against Aedes aegypti and Culex pipiens (Diptera, Culicidae) breeding in artificial containers. Laboratory experiments were performed to determine the daily predation rate, differential predation on each mosquito larval instar, selective predation on...

In this work we record two species belonging to the polyclad family Pseudocerotidae from the littoral zone of the Península Valdés (Patagonia, Argentina). This is the first record of members of Cotylea and the third of Polycladida from Argentina. The two new records are Phrikoceros mopsus, a species described for Brazil and Colombia and Thysanozoon...

A new species of the genus Temnosewellia (Platyhelminthes, Temnocephalida, Temnocephalidae), Temnosewellia vietnamensis n. sp., is described from Quangnam Province, Vietnam, ectosymbiont on the external carapace of Villopotamon thaii Dang & Ho, 2003 (Crustacea, Decapoda, Potamidae). Records of temnocephalans from the region of Southeast Asia are su...

Brusa, Francisco, Damborenea, Cristina, Quiroga, Sigmer (2009): First records of Pseudocerotidae (Platyhelminthes: Polycladida: Cotylea) from Patagonia, Argentina. Zootaxa 2283: 51-59, DOI: 10.5281/zenodo.191231

FIGURE 2. Phrikoceros mopsus. A, diagram of dorsal view. B, ventral morphology. C, dorsal view of pseudotentacles. D, ventral view of pseudotentacles. E, sagittal reconstruction of genital system portion. bl: black line; ce: cerebral eye; de: dorsal eyes of the pseudotentacle; fg: female gonopore; g: cement glands; m: mouth; mg: male gonopore; p: p...

FIGURE 3. Thysanozoon brocchii. A, dorsal view of live specimen. B, ventral view of live specimen. Arrow heads show male gonopores.

FIGURE 1. Phrikoceros mopsus. A, dorsal view of live specimen. B, detail of the anterior end. Arrow-heads show the interruption of the marginal black line at the apical region of the pseudotentacles. C, dorsal view of the anterior end with cerebral eyes (arrow-head). D, dorsal view of the anterior end; arrow head shows some of the ventral pseudoten...

Two new species of Gieysztoria are described, along with the first record of two species of this genus in Argentina. Gieysztoria atalaya n. sp. has a sclerotic stylet with a window on one of its sides and a belt bearing three types of spines. One hollow spine, originated under the window, is basally broad and tapers towards its blunt distal end. Th...

Two new species of Gieysztoria are described, along with the first record of two species of this genus in Argentina. Giey-sztoria atalaya n. sp. has a sclerotic stylet with a window on one of its sides and a belt bearing three types of spines. One hollow spine, originated under the window, is basally broad and tapers towards its blunt distal end. T...

Temnocephala lamothei n. sp., a commensal of Pomella megastoma (Sowerby, 1825), is described herein from specimens collected at Arroyo Yabotí-Miní (Misiones province, Argentina). Juveniles and adults were removed from the mantle cavity by host relaxation. Distinctive characters of the new species are: non-partitioned intestine; conical cirrus with...

Two new species of Gieysztoria are described, along with the first record of two species of this genus in Argentina. Giey-sztoria atalaya n. sp. has a sclerotic stylet with a window on one of its sides and a belt bearing three types of spines. One hollow spine, originated under the window, is basally broad and tapers towards its blunt distal end. T...

FIGURE 1. Gieysztoria atalaya n. sp. A, photograph of the stylet. B, dorsal general view in vivo. C, reconstruction of the stylet (a, b, and c indicate the three types of spines). D, sagittal reconstruction. Scales A and C: 50 m. Scales B and D: 100 m. For abbreviations see Figure 8.

FIGURE 3. Gieysztoria evelinae. A, photograph of the caudal region (arrow indicates duct of the caudal glands). B, general ventral view in vivo. C, sagittal reconstruction. Scale A: 10 m. Scale B: 200 m. Scale C: 100 m. For abbreviations see Figure 8.

FIGURE 5. Gieysztoria hymanae. A, detail of the copulatory apparatus. B, general view in vivo. C, sagittal reconstruction. Scale A – C: 100 m. For abbreviations see Figure 8.

FIGURE 6. Nygulgus evelinae. A, stylet. B, general view. C, sagittal reconstruction. Scale A: 30 m. Scale B and C: 100 m. For abbreviations see Figure 8.

FIGURE 8. Microphotograph of sagittal sections of Gieysztoria evelinae. A, general view. B, detail of bursa copulatrix. C, detail of anterior region. D, detail of stylet. Microphotographs of sagittal sections of Nygulgus evelinae. E, general view. Scale A – E: 50 µm. b: brain, bc: bursa coplatrix, cg: caudal glands, e: eye, eg: egg, g: gonopore, ga...

FIGURE 2. Gieysztoria matilde n. sp. A, photographs of the stylet. B, general view of adult specimen in vivo. C, diagram of stylet. Scale A and C: 50 m. Scale B: 100 m. For abbreviations see Figure 8.

FIGURE 4. Gieysztoria evelinae. Microphotograph of the stylet, (SEM). A, general view. B, detail of the area with spines. r 1, r 2, indicate de rings of the stylet, and numbers 1 – 3 indicate the type of spines. Scale A: 20 µm. Scale B: 1 µm.

FIGURE 7. Microphotographs of sagittal sections of Gieysztoria hymanae. A, general view. B, detail of genital region. Microphotograps of Gieysztoria atalaya sp. n. Sagittal sections. C, general view. D, detail of digestive system. E, detail of genital region. F: horizontal section of stylet region. Scale A – F: 50 m. For abbreviations see Figure 8.

From 1997 to 1999, the fauna of free‐living Platyhelminthes of the rias ecosystem was studied along the Galician and Cantabrian coast in northern Spain. In total, 72 platyhelminth species are listed in this study. Forty‐two species represent new records for the Iberian Peninsula, three of which represent new genera records. A new species belonging...

Two new species of Dalyellidae, Dalyellia callvucurai n. sp. and Gieysztoria namuncurai n. sp., are described from temporary freshwater environments in central Buenos Aires Province, Argentina. The ultrastructure of the stylets of both species is also described. The new species of the genus Dalyellia is the second species of the genus found in the...

Pomacea canaliculata is a common gastropod in freshwater habitats from Central and Northern Argentina, extending northwards into the Amazon basin. Several Platyhelminthes have been reported associated to P. canaliculata, sharing an intimate relationship with this gastropod host. The objectives of this study were to describe the symbiotic species as...

In this work, two new species of the genus Macrostomum (M. velastylum n. sp. and M. puntapiedrensis n. sp.) are described from the littoral benthos of the Río de la Plata estuary, Argentina. This is the first description of members of the Macrostomidae from Argentina, and of a species documented from both limnic and brackish-water environments. Mac...

Many species of turbellarians (Platyhelminthes) are known to live associated with other organisms, especially invertebrates, as commensals or parasites. The family Graffillidae (Rhabdocoela) includes two genera that parasitize mollusks, Graffílla and Paravortex. Within the latter genus, six species were described as associated with mollusks. In oth...

Twenty-one free-living species of turbellaria (Platyhelminthes) were found in the Pacaya-Samiria National Reserve (Loreto, Peru), a Peruvian Amazon floodplain. The total 21 observed taxa comprise five species of Catenulida, two species of Macrostomida, two species of "Lecithoepitheliata", 10 species of Rhabdocoela and two species of Tricladida. Mos...

In this work a new benthic species of the genus Plagiostomum is described from the littoral zone of Río de la Plata (Argentina). Plagiostomum cilioejaculator sp. n. is the fourth eyeless species of the genus to be described. The male reproductive system is characterized by a muscular and somewhat curved penis, approximately 260 µm long. The ejacula...