Os tricladidos terrestres apresentam alto grau de endemismo, devido especialmente è sua capacidade de locomoção reduzida. No Rio Grande do Sul, dados sobre as comunidades de planárias terrestres são principalmente conhecidos de áreas de floresta ombrófila mista. O presente estudo teve como objetivo analisar a composição das espécies de planárias terrestres em remanescentes de floresta estacional decidual, situados na região nordeste do Rio Grande do Sul. Com base em coletas diurnas diretas foram registradas 26 espécies, pertencentes ès subfamílias Geoplaninae e Rhynchodeminae. Foram registrados os seguintes gêneros de Geoplaninae: CephaloflexaCarbayo & Leal-Zanchet, 2003, Choeradoplana Graff, 1896, Imbira Carbayo et al., 2013, IssocaFroehlich, 1955, LuteostriataCarbayo, 2010, Obama Carbayo et al., 2013, Paraba Carbayo et al., 2013, Pasipha Ogren & Kawakatsu, 1990 e XerapoaFroehlich, 1955, além do grupo coletivo Pseudogeoplana Ogren & Kawakatsu, 1990 e do gênero de Rhynchodeminae Rhynchodemus Leidy 1851. O gênero Obama apresentou a maior riqueza de espécies (S=6), seguido por Paraba (S=4) e Pasipha (S=3). Dezoito espécies foram registradas exclusivamente em uma das áreas de estudo, enquanto oito espécies ocorreram em ambas localidades. Amplia-se a distribuição conhecida de Luteostriata abundans (Graff, 1899), Choeradoplana iheringiGraff, 1899, Obama ficki (Amaral & Leal-Zanchet, 2012), Imbira guaiana (Leal-Zanchet & Carbayo, 2001) e Pasipha hauseri (Froehlich, 1959). Além disso, os resultados enfatizam a importância de ampliação dos estudos taxonômicos de planárias terrestres, bem como das áreas de estudo no sul do Brasil.

Land flatworms show high endemism due to their restricted mobility. In southern Brazil, land flatworm communities have been found mainly in areas of ombrophilous forests. Thus, this study documents land planarian species composition in remnants of deciduous seasonal forest in the northeast region of southern Brazil. Direct, diurnal samplings reveal the occurrence of 26 species of land flatworms, of which one belongs to the subfamily Rhynchodeminae and the others to the subfamily Geoplaninae. The Rhynchodeminae genus Rhynchodemus Leidy 1851 and the following Geoplaninae genera occurred: CephaloflexaCarbayo & Leal-Zanchet, 2003, Choeradoplana Graff, 1896, Imbira Carbayo et al., 2013, IssocaFroehlich, 1955, LuteostriataCarbayo, 2010, Obama Carbayo et al., 2013, Paraba Carbayo et al., 2013, Pasipha Ogren & Kawakatsu, 1990 and XerapoaFroehlich, 1955, besides the collective group Pseudogeoplana Ogren & Kawakatsu, 1990. The genus Obama had the highest species richness (S=6), followed by Paraba (S=4) and Pasipha (S=3). Eighteen species were recorded exclusively in one of the two study areas, and eight species occurred in both sites. The known distribution of Luteostriata abundans (Graff, 1899), Choeradoplana iheringiGraff, 1899, Obama ficki (Amaral & Leal-Zanchet, 2012), Imbira guaiana (Leal-Zanchet & Carbayo, 2001) and Pasipha hauseri (Froehlich, 1959) is increased. Results emphasize the relevance of expanding taxonomic studies on land flatworms and including more study areas in southern Brazil.

Os turbelários são encontrados em uma grande variedade de hábitats aquáticos, sendo abundantes inclusive em áreas úmidas temporárias. Diversos turbelários são predadores de topo nos seus microhabitats, muitos deles alimentando-se de zooplâncton. No entanto, raramente os turbelários são considerados em inventários de diversidade. Informações sobre sua diversidade nos ecossistemas límnicos brasileiros provêm principalmente de estudos taxonômicos. No Rio Grande do Sul, há um grande número de áreas úmidas, sendo a maioria delas representadas por lavouras de arroz. Esses ecossistemas manejados, embora tenham alto impacto sobre áreas naturais, podem exercer um importante papel na conservação da biodiversidade aquática. Este estudo teve por objetivo inventariar os turbelários ocorrentes em áreas de cultivo de arroz irrigado de três localidades da Planície Costeira do sul do Brasil (Cachoeirinha, Santo Antônio da Patrulha e Camaquã). Foram registradas 144 espécies de turbelários, distribuídas em seis grupos taxonômicos (Catenulida, Macrostomida, Lecithoepitheliata, Proseriata, Rhabdocoela e Tricladida). Vinte e três espécies são registradas pela primeira vez para o Rio Grande do Sul. Catenulida apresentou a maior abundância relativa em Cachoeirinha, seguida por Rhabdocoela, enquanto nas outras duas localidades, a maior abundância relativa foi de Tricladida, seguida por Catenulida. Os resultados sugerem que algumas espécies demonstram alto grau de especificidade de hábitat, pois cerca de 38% dos turbelários ocorreram em apenas uma das áreas de estudo. Apesar da existência de poucos inventários de turbelários em áreas úmidas naturais do Brasil, impedindo uma comparação entre áreas úmidas naturais e manejadas, os resultados indicam uma elevada riqueza de espécies de turbelários nas áreas de estudo.

Turbellarians occur in a variety of wetlands, being also abundant in temporary water bodies. Several turbellarians are top predators in their microhabitats, many of them feeding on zooplankton. However, they are seldom taken into account in biodiversity studies. Information on turbellarian diversity in Brazilian freshwater ecosystems mainly came from taxonomical studies. In southern Brazil, there are a high number of wetlands, most of them represented by rice fields. Despite their impact on natural areas, these managed ecosystems can play an important role in freshwater biodiversity conservation. The aim of the present work was to report on an inventory done in irrigated rice fields of three areas of the Coastal Plain of southern Brazil, viz. Cachoeirinha, Santo Antônio da Patrulha e Camaquã. We found 144 species of freshwater turbellarians, distributed in six taxonomic groups (Catenulida, Macrostomida, Lecithoepitheliata, Proseriata, Rhabdocoela, and Tricladida). Twenty-three species are recorded for the first time for Brazil. Catenulida showed the highest relative abundance in Cachoeirinha, followed by Rhabdocoela. In Santo Antônio and Camaquã, Tricladida had the highest relative abundance, followed by Catenulida. Results suggest that some turbellarian species show a high level of habitat specificity with only 38% of the registered turbellarians occurring in a single study area. Although there is a paucity of turbellarian inventories in Brazilian natural wetlands, hampering a comparison between natural and managed wetlands, results indicate high species richness in the areas studied.

Os tricladidos terrestres são predadores de topo de cadeia no seu microhábitat, alimentando-se de outros invertebrados de solo. A riqueza de espécies de tricladidos pode indicar a diversidade de outros grupos. A composição das comunidades de planárias terrestres da Floresta Estacional Decidual, que ocupa um quarto da cobertura vegetal do Estado do Rio Grande do Sul, é pouco conhecida. O presente trabalho teve como área de estudo o maior remanescente dessa formação florestal no Rio Grande do Sul, apresentando os seguintes objetivos: inventariar as espécies de planárias terrestres no Parque Estadual do Turvo (PE-Turvo) e comparar as comunidades desse Parque com as de outras áreas do estado com inventários desses tricladidos. Na área de estudo, foram inventariadas 26 espécies, sendo duas pertencentes às subfamílias Rhynchodeminae e Bipaliinae, e as demais, à subfamília Geoplaninae. Além dos gêneros Rhynchodemus Leidy 1851 e Bipalium Stimpson, 1857, foram registrados os seguintes gêneros de Geoplaninae: Geoplana Stimpson 1857, Choeradoplana Graff 1896, Pasipha Ogren & Kawakatsu 1990 e Notogynaphallia Ogren & Kawakatsu 1990, além do grupo coletivo Pseudogeoplana Ogren e Kawakatsu, 1990. O maior número de espécies foi registrado para o gênero Geoplana (10), seguido pelo gênero Pasipha (4). Geoplana rubidolineata Baptista & Leal-Zanchet, 2005 havia sido registrada anteriormente apenas para sua localidade-tipo, no nordeste do estado. Bipalium kewense Moseley, 1878, de distribuição cosmopolita, foi encontrada apenas em local submetido a alto impacto antrópico, não tendo sido registrada em áreas de floresta. Para comparar as comunidades de planárias terrestres do PE-Turvo com as de outros tipos de vegetação do estado, utilizou-se o método de ordenação NMDS. Essa análise indicou que as comunidades de planárias terrestres do PE-Turvo e de outras áreas de Floresta Decidual, Semidecidual e Floresta Ombrófila Densa diferenciam-se das comunidades de áreas de Floresta Ombrófila Mista. A alta riqueza de espécies observada no PE-Turvo reforça sua importante contribuição para a conservação da diversidade regional.

Land triclads are top-predators in their microhabitats, feeding on other soil invertebrates. The species richness of triclads may indicate the diversity of other faunal groups. The community composition of land flatworms of areas of Deciduous Forest, which occupies a quarter of the vegetal cover of the state, is poorly known. The present study inventoried land planarians of the largest remnant of this type of forest in the State of Rio Grande do Sul, the Turvo State Park (SP-Turvo) and compared their communities with those of other localities of the state with inventories of land flatworms. We inventoried 26 species, two of them belonging to the subfamilies Rhynchodeminae and Bipaliinae, and 24 to the subfamily Geoplaninae. Besides the genera Rhynchodemus Leidy 1851 and Bipalium Stimpson, 1857, the following Geoplaninae genera were recorded: Geoplana Stimpson 1857, Choeradoplana Graff 1896, Pasipha Ogren & Kawakatsu 1990 and Notogynaphallia Ogren & Kawakatsu 1990, as well as the collective group Pseudogeoplana Ogren & Kawakatsu, 1990. The highest species richness was registered for the genus Geoplana (10), followed by the genus Pasipha (4). Geoplana rubidolineata Baptista & Leal-Zanchet, 2005 was previously only known from its type-locality, located in the northeast of the state. Bipalium kewense Moseley, 1878 which shows a cosmopolitan distribution was observed in a man-disturbed area, not being registered in forest areas. We employed an NMDS ordination to compare land planarian communities of the Turvo State Park to those of other types of forest of the state. The analysis indicated that land planarian communities of the Turvo State Park and those of other areas with Deciduous, Semideciduous and Dense Ombrophilous Forests differ from those of Mixed Ombrophilous Forests of the region. The high observed species richness in the Turvo State Park reinforces its important contribution for the conservation of the regional diversity.

Land flatworms are carnivorous, mainly predators. However, knowledge on their predatory behavior and prey preference is very scarce. This paucity of data is a limiting factor in the study of their biology and organismal ecology, resulting in a very difficult task to breed them in the laboratory for prolonged periods if prey preference and predation frequency are unknown. We investigated the predatory behavior of Notogynaphallia abundans (Graff, 1899), Geoplaninae, based on laboratory experiments. In order to determine its predatory choices, we offered mollusks, earthworms, arthropods, and other land flatworms. Only land isopods were accepted, with an average consumption of 3.4 individuals per week. Linear regression showed a positive relationship between the number of consumed isopods and the increase/decrease in body mass. Consumption resulting in an increase in body mass was ca. four isopods per week. Predatory behavior, with a mean time-span of 28 min 45 s ± 15 min 47 s, includes encounter and capture of prey, immobilization, handling and feeding. Variation in the duration of this activity in N. abundans is clearly due to variations in the time necessary for transferring the prey from either the anterior or posterior thirds of the body to the mouth, as well as for external digestion and ingestion. In order to capture very active and fast-moving animals such as land isopods, N. abundans employs various strategies, using either the anterior or the posterior body regions to press the prey against the ground or against its own body, thus allowing it to deal with various responses by the prey, and thereby maximizing predatory success. Similar to other flatworms, both physical holding and entrapment in a mucous secretion are of fundamental importance for prey-immobilization. The different strategies employed by land flatworms in their predatory behavior are discussed, and behavioral plasticity in the capture and immobilization of prey in different platyhelminth groups is emphasized.

Dez espécies de microturbelários dulciaqüícolas, pertencentes a três ordens, Catenulida, Macrostomida e Rhabdocoela, foram coletados em sete localidades situadas no Nordeste do estado do Rio Grande do Sul, Brasil. Duas dessas espécies, Macrostomum johni Young, 1972 e Mesostoma productum (Schmidt, 1848), são registradas pela primeira vez para o Brasil, sendo o registro de M. johni o primeiro também para a Região Neotropical. Todas as espécies são registradas pela primeira vez para o estado do Rio Grande do Sul.

Ten species of freshwater microturbellarians of three ordens, Catenulida, Macrostomida and Rhabdocoela, were collected in seven sites situated in the Northeast region of Rio Grande do Sul, Brazil. Two species, Macrostomum johni Young, 1972 and Mesostoma productum (Schmidt, 1848), are cited for the first time for Brazil, the citation of M. johni being also the first one for the Neotropical Region. All species are cited for the first time for the state of Rio Grande do Sul.

A new species of Notogynaphallia Ogren & Kawakatsu, 1990, from Southern Brazil, is described. Notogynaphallia ceciliae sp. nov. has an elongated body with parallel margins and five dorsal dark longitudinal stripes on a yellowish ground. It possess branched efferent ducts, each branch opening separately into the anterior and median thirds of the long prostatic vesicle. Comparative commentaries on the most important characters of the external and internal morphology of the 23 species of the genus are also presented, so delimiting smaller inside groups.

The histology of the salivary glands of six species of Limacoidea, Boettgerilla pallens Simroth, 1912, Deroceras laeve (Müller, 1774), Deroceras reticulatum (Müller, 1774), Deroceras rodnae Grossu & Lupu, 1965, Malacolimax tenellus (Müller, 1774) and Lehmannia marginata (Müller, 1774), and a species of Milacidae, Tandonia budapestensis (Hazay, 1881) is comparatively described herein. In the glandular parenchyme four to five secretory cell types are distinguished and characterised, besides a cell type which is probably undifferentiated. The secretory cell types are classified into two groups, mucous and serous cells. Two types of mucous cells and two to three types of serous cells are distinguished. The salivary glands of the herein studied Limacoidea and Milacidae show a duct system composed of intralobular, interlobular and main ducts, each one presenting a characteristic type of epithelial lining. The results are comparatively discussed with the data available in the literature, in order to verify the correspondence between the different cell types described for other Pulmonata.

Choeradoplana iheringi Graff, 1899 was described on specimens proceeding from Taquara, Rio Grande do Sul, Brazil. Afterwards, RIESTER (1938), MARCUS (1951) and FROEHLICH (1955) analyzed specimens from southeast Brazil, identifying them as C. iheringi. In this study samples of C. iheringi from São Francisco de Paula, a site next to the type-locality, and specimens from the Southeast (Salesópolis, state of São Paulo), are comparatively analyzed. It was observed that the external morphology of the specimens from São Francisco de Paula and from Salesópolis is concordant with the original description of C. iheringi, as well as that by RIESTER (1938) and MARCUS (1951). The pharynx is better designated as bell-form, and not collar-form as described by GRAFF (1899). The copulatory apparatus is characterized by the presence of an intra-bulbar prostatic vesicle, consisting of two regions, an ental tubular one and an ectal one of variable shape; absence of penis papilla; and a male atrium, elongated and highlypleated. The copulatory apparatus of C. iheringi described by GRAFF shows some anatomical characteristics that distinguish it from the material studied by other authors, and from the material analyzed here. Some anatomical and histological characters of the copulatory apparatus distinguish the specimens from São Francisco de Paula from those of Salesópolis which are assigned to populational and/or physiological differences. The specimens from São Francisco de Paula and Salesópolis, as well as those analyzed by RIESTER (1938) and MARCUS (1951), are confirmed as C. iheringi Graff, 1899.

The digestive gland of Phyllocaulis soleiformis is a compound tubular gland. The secretory tubules are made up of two main cell types: the digestive cells and calcic cells. The digestive cells are the most numerous, usually columnar, and exhibit three different functional stages: absorptive, secretory and excretory. These cells contain two cytoplasmic granules types and, in the excretory stage, most of the cell is occupied by a large vacuole. The calcic cells occursingly or frequently in groups of two or three, are triangular shaped and have distinct apical granules, and yet calcic histochemical detected granules. In addition, there is a third cell type, without characteristic cytoplasmic granules and which correspond to the undifferentiated cells. The excretory duets system are represented by anterior and posterior vestibules, which branche to form the duets, that communicate with the secretory tubules. These excretory duets are lined with a simple epithelium of ciliated columnar cells, followed by a layer of connective tissue with circular and longitudinal muscular fibers. Subepithelial mucous cells are present only in the vestibules.