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Avocado is one of the most commonly preferred shades grown tree crop under Coffee ecosystem. In view of that, Peninsula of Nicoya and Cost Rica farmer was rated avocado (Persea americana L. Mill) is a primary shade tree crop under coffee plantation at the level of 66.3 per cent and it ranked as a fourth position after the Inga spp., Guazumala ulmiflora and Cardia alliodoara. Hence, the avocado is a commercially important shade cum fruit yielding tree under coffee ecosystem which has cultivating both in humid tropic as well as subtropical climates of throughout the world. The tree is basically grown as the forest species but later on as a shade growing tree under coffee cultivation because of high nutritional and medicinal values of fruit and it makes for wider diversity. Thereafter it was entered into the other parts of the world from Central America and Mexico. The tree is of multipurpose in nature and also helps to avoid the soil and water erosion by way of its wider spread canopy. Generally, Avocado leafs reduce the beating action of rain drops which in-turn minimize the soil erosion. The soil enrichment by adding the leaf litter continuously is an advantage in the coffee plantations. It yields in the additional economic returns after three to five years of establishment. Hence, the establishment of shade tree under coffee ecosystem will give additional income to the coffee growers, which mainly helps on lean period of coffee cultivation.
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As a consequence of the finding of Arcangeliella scissilis in Costa Rica, we thought to carry out a full description of this material, giving some aspects on its taxonomy, ecology and distribution.
We studied blood parasites in wild birds within Hitoy Cerere Biological Reserve and Barbilla National Park in Costa Rica during the rainy season of 2004. We examined blood samples from 248 and 114 birds, respectively. Protozoan parasites of the genus Haemoproteus as well as microfilariae were found. Prevalence of Haemoproteus in birds was 0.8% and 4.4% in Hitoy Cerere and Barbilla, respectively, and differences were significant. Prevalence of infection by microfilariae was 8.1% and 3.5%, respectively, however, differences were not significant. Based on morphological characteristics, we divided microfilariae into two groups and nine morphotypes. In Hitoy Cerere, there were microfilariae of all nine morphotypes whereas in Barbilla we only found two morphotypes.
Five new specimens of the poorly known Sanborn's bonneted bat, Eumops hansae (Chiroptera: Molossidae), are reported for Costa Rica's central and northern Pacific lowlands based on a subadult male collected in 1990 and four adult females collected in 2003. We also report the second known specimen of Eumops underwoodi from Costa Rica and additional specimens of Cynomops mexicanus, Eumops glaucinus, Molossus molossus, and Molossus pretiosus. Most of the females captured in August and April were either lactating or pregnant, suggesting that parturition in these molossids occurs in the late dry season and the early to middle rainy season, periods when insects are especially abundant in this dry forest. Characters used previously to distinguish between the similar-sized E. hansae and E. nanus are evaluated, and external and cranial measurements for the specimens of E. hansae are provided. The best single character for distinguishing the two species is size and shape of the upper incisors. In E. hansae, the upper incisors are thin and recurved, whereas they are thick, straight, and slightly procumbent in E. nanus. The six sympatric species of free-tailed bat found in the gallery forest along the Río Enmedio vary in size, jaw thickness, and wing shape suggesting coexistence through resource partitioning in this molossid bat assemblage.
A species of Sarcocystis is reported from a naturally infected African grey parrot, Psittacus erithacus, from Costa Rica. Only mature sarcocysts, measuring up to 2 mm in length and up to 750 μm in width, were observed. The sarcocyst wall was smooth. The villar protrusions on the sarcocyst wall were up to 5 μm long and up to 1.1 μm wide; they were folded over the sarcocyst wall giving a thin-walled appearance. The microtubules in villar protrusions were smooth and confined to villar protrusions. Bradyzoites in sections were 5.4–6.6 × 1.3–2.0 μm in size. Sequencing the small subunit and first internal transcribed spacer portions of ribosomal DNA related this parasite to, but distinguished it from, previously characterized species of Sarcocystis that encyst in the musculature of birds and complete their sexual development in New World opossums of the genus Didelphis. This evidence suggests that the parrot may have acquired its infection from an opossum from which it suffered a debilitating attack a year prior to the onset of depression, anorexia, and ultimately death.
The fauna of ptyctimous mites of Costa Rica has been described and analysed. At nearly 200 localities in all provinces of Costa Rica, 76 species of ptyctimous mites (6 Mesoplophoridae, 31 Euphthiracaroidea, 39 Phthiracaroidea) represented by over 3300 specimens have been found. Over 40% of species are new to science. Descriptions of 32 new species have been given: Mesoplophora (Parplophora) bacula sp. nov., Oribotritia alajuela sp. nov., O. allocota sp. nov., O. brevisetosa sp. nov., O. laselve sp. nov., O. nasalis sp. nov., O. partita sp. nov., Mesotritia semota sp. nov., Euphthiracarus evexus sp. nov., E. pedanos sp. nov., E. serangos sp. nov., E. tesselatus sp. nov., E. tumidus sp. nov., Rhysotritia meristos sp. nov., FL parallelos sp. nov., Phthiracarus totus sp. nov., Plonaphacarus baculus sp. nov., Austrophthiracarus nexilis sp. nov., A. retrorsus sp. nov., Austrophthiracarus zeuktos sp. nov., Arphthicarus allocotos sp. nov., A. iubatus sp. nov., A. pararidiculus sp. nov., A. parasaucius sp. nov., A. pervalidus sp. nov., Protophthiracarus clandestinus sp. nov., P. heteropitosus sp. nov., P. heterosetosus sp. no Notophthiracarus pedanos sp. nov., Atropacarus (Hoplophorella) frondeus sp. nov., Atropacarus (Atropacarus) antrosus sp. nov., A. (A) folious sp. nov. The identification keys of the families, genera and species with figures of the species are presented. On the basis of the data collected, it is difficult to distinguish between the fauna of ptyctimous mites from the western and eastern coast, or north-western and south-eastern parts of the country. The most abundant species, whose representatives make over 30% of all ptyctimous mite specimens found in all samples, is pantropical Plonaphacarus kugohi occurring mainly in the rain forest La Selva. The fauna of ptyctimous mites of Costa Rica is to a large extent harmonic. Euphthiracaroidea are represented by all main genera, whereas from among Phthiracaroidea the genera Hoplophthiracarus and Steganacarus have not been represented, and the gondwanian Notophthiracarus was represented by only one species. The fauna of ptyctimous mites in Costa Rica is typically Neotropical. Over 21% species are widespread: semicosmopolitan and pantropical, the others are neotropical. From among the latter only 18% are widespread in the Neotropical region, 35% are bound with Mexican subregion, and nearly half (46%) are restricted to Costa Rica, including 17% of endemic species. The fauna of ptyctimous mites of the region is weakly related to the fauna of Nearctic region, only a few of the species reach the south states of the USA.
A species of Sarcocystis is reported from two naturally infected Buffon’s macaws (Ara ambigua) from Costa Rica. Only mature sarcocysts, measuring up to 950 μm in length and up to 75 μm in width, were observed. By light microscopy the sarcocyst wall was thin (< 1 μm thick) and smooth. The villar protrusions on the sarcocyst wall were up to 4.0 μm long and up to 0.6 μm wide; they were folded over the sarcocyst wall giving a thin-walled appearance. The microtubules in villar protrusions were smooth and confined to villar protrusions. Bradyzoites in sections were 4.0–5.9 × 0.8–1.8 μm in size. Structurally, sarcocysts from the macaw appeared different from sarcocysts of other avian species. This is the first report of Sarcocystis infection in this host.
Roosting ecology and its correlates are among the major forces driving the evolution of bats. However, roost ecology remains one of the most poorly understood topics on the basic biology of bats. Ectophylla alba is endemic to Central America with a very small distribution. This species generally modifies leaves of a certain size within the genus Heliconia. Here we explore this species' habitat preferences for the construction of its roosts. We identified three variables as the requirements of a suitable tent-building habitat: canopy coverage, understory coverage between 0–1 m of height, and density of Heliconia. Our results show that the process of habitat selection for roost construction is highly specialized to an intermediate stage of secondary succession, which in turn, makes Ectophylla even more vulnerable to extinction than previously believed.
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