Two new species of Dugesia (Platyhelminthes, Tricladida, Dugesiidae) from the tropical monsoon forest in southern China

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.

Tropical Monsoon Forest Thermodynamics Based on Remote Sensing Data

This paper addresses thermodynamic variables that characterize the energy balance and structure of the solar energy transformation by the ecosystems of deciduous tropical forests. By analyzing the seasonal dynamics of these variables, two main states of the thermodynamic system are determined: the end of the drought season and the end of the wet season. Two sub-systems of solar energy transformation are also defined: a balance system that is responsible for the moisture transportation between the ecosystem and atmosphere; and a structural bioproductional system responsible for biological productivity. Several types of thermodynamic systems are determined based on the ratio between the invariants of the variables. They match the main classes of the landscape cover. A seasonal change of thermodynamic variables for different types of thermodynamic systems is additionally studied. The study reveals that temperature above the forest ecosystems is about 4° lower than above the open areas during most of the year.

Habitat and dung preferences of scarab beetles of the subfamily Scarabaeinae: a case study in a tropical monsoon forest in Sri Lanka

We studied the food and habitat preferences of beetles of the subfamily Scarabaeinae in a protected tropical monsoon forest, the Wasgomuwa National Park in Sri Lanka. While gaining an insight into the capacity of different resources to support dung beetles, we tested the hypothesis that, in a landscape with a mosaic of habitat types and a diversity of large mammals, specialization facilitates coexistence of the scarabs. Pitfall traps were laid in five distinct habitat types (forest, riverine, sandy banks, scrub and grassland), and baited with five dung types (leopard, cervid, elephant, bear and buffalo). Four hundred and fifty seven beetles of 22 species in seven genera were recorded. Significant differences were seen in the species richness and abundance of dung beetles between different habitats and dung types, indicating habitat and food preferences. The highest richness of scarabs was in the riverine habitat and in leopard dung. Niche breath values of the individual species indicated differences in the degrees of specialization, while niche overlap values indicated a greater sharing of dung beetle species between similar habitats and dung types than between dissimilar ones. These findings provide evidence that selectivity of habitat, and dung, may be important in promoting coexistence among the scarabs in a tropical environment.