No abstract

Two new genera of geoplaninid land planarians are described. Cephalic specialisations, mainly external morphology and musculature development, partially define each genus. Cephaloflexa, gen. nov. shows some peculiar characteristics, such as a gradual narrowing of the anterior third of the body and an upwards roll of the anterior tip, the absence of eyes and sensory pits on the apex, and the existence of a retractor muscle derived from the ventral cutaneous longitudinal musculature. Geoplana bergi Graff, 1899 is allocated to Cephaloflexa and is designated as the type species. The ventral cutaneous longitudinal muscles of Supramontana, gen. nov. (monotypic), are partially sunk into the mesenchyme, thus constituting a cephalic retractor muscle. A new species of each genus is also described. The external morphology and anatomy of the cephalic region of the new genera and of Geoplana Stimpson, 1857, Choeradoplana Graff, 1896 and Issoca C. G. Froehlich, 1955 are analysed. Emendations to the diagnoses of Issoca and Choeradoplana are proposed based on cephalic differentiations. Spanish abstractSe decriben Cephaloflexa, gen. nov. y Supramontana, gen. nov., dos nuevos géneros de planarias terrrestres de la subfamilia Geoplaninae, ambos caracterizados por especializaciones cefálicas, como la morfología externa y el desarrollo muscular. Se describe una nueva especie de cada género. Se transfiere Geoplana bergi Graff, 1899 para el género Cephaloflexa y se la designa especie tipo. Cephaloflexa, gen. nov. presenta características peculiares, como el tercio anterior del cuerpo muy fino, región anterior enrollada hacia el dorso, ausencia de ojos y fosetas sensoriales en el ápice anterior del cuerpo, y un músculo retractor derivado de la musculatura subcutánea longitudinal ventral. Supramontana, gen. nov., género monotípico, tiene parte de la musculatura subcutánea longitudinal ventral hundida en el mesénquima y transformada en la región anterior en un músculo retractor cefálico. Se analiza la morfología externa y la anatomía de la región cefálica de Geoplana Stimpson, 1857, Choeradoplana Graff, 1896 e Issoca Froehlich, 1955 y se proponen enmiendas a las diagnosis de Choeradoplana e Issoca basadas en las diferenciaciones cefálicas.

Abstract. Land flatworms (Platyhelminthes: Terricola) are sensitive to environmental changes and might be used as biological indicators of the degree of disturbance of their habitats. Nevertheless, studies on the structure of land flatworm communities are rare. In the present study, we investigated the terrestrial flatworm communities in two types of ombrophilous forest, Atlantic forest and Araucaria forest, aiming to answer the following questions: (1) Is the community structure of the two types of ombrophilous forest different? (2) Are there differences, regarding community structure, among distinct fragments of Araucaria forest? (3) Are there indicators of edge effects in these communities? The study site, the National Park of Aparados da Serra, is mainly covered, at high altitudes, by fragments of Araucaria forest immersed in a matrix of open areas (grasslands) and, in low altitudes, by a continuous Atlantic forest. We conducted monthly surveys in the two types of forest with three replications per forest type over a period of 2 years. Results indicated that: (1) community structure is clearly distinct between the two types of forest, as well as among fragments of the Araucaria forest; (2) there are no apparent edge effects; (3) the diversity indices of the two types of ombrophilous forest are not significantly different (Atlantic forest—H′=2.87, Araucaria forest—H′=2.55; p>0.05); and (4) there are significant differences in diversity indices between two fragments of Araucaria forest (H′=2.92 and 2.47; p<0.001). The following factors could affect community structure: type of vegetation, degree of human disturbance, and abiotic factors, such as pH and temperature.

No abstract

Abstract. Araucaria forests are among the most threatened biomes of one of the world's 25 biodiversity hotspots, the south Brazilian Atlantic Rain Forest. This study was focused on flatworm community structure in three protected areas located on the eastern border of the Araucaria Plateau in south Brazil. We addressed three main questions: (1) How species‐rich are Araucaria forests? (2) Are there any differences in the community structure within the three areas? (3) What is the distribution pattern of land flatworms in this type of forest? A total of 51 flatworm species in ten genera and two subfamilies were found. Non‐metric multidimensional scaling analysis showed that the assemblage structure differed within the three areas. The abundance and richness varied in time, being affected by an interaction between season and areas. Araucaria forests on the eastern border of the Araucaria Plateau should be considered a hotspot of land planarian diversity, harboring an estimated 64 species. The high combined species richness in the protected areas studied emphasizes the importance of their preservation. Notwithstanding their close proximity, they are not redundant in maintaining regional biodiversity.

The genera Cratera Carbayo et al., 2013 and Obama Carbayo et al., 2013, belonging to the subfamily Geoplaninae, were recently proposed to encompass some of the species that belonged to the genus Geoplana Stimpson, 1857. Herein we describe two new species of Geoplaninae, occurring in areas of ombrophilous forest which belong to the southern portion of the Brazilian Atlantic Rain Forest. The species are sympatric in their type-locality. In general, both new species herein described match the diagnostic characteristics of their genera. However, some of these features are noteworthy when characters of the new species are taken into consideration, especially the pattern of the sensory pits and the morphology of the prostatic vesicle. Both species are differentiated from their congeners by a combination of morphological characteristics, corroborated by phylogenetic analyses of the cytochrome c oxidase subunit I gene, using maximum likelihood and Bayesian inference, as well as the Automatic Barcode Gap tool.

No abstract

No abstract