Odonata of the Osa Peninsula - Frontier

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abundance of species between samples) and is therefore less likely to overestimate the species richness (Colwell et al. 2004). Results General I captured a total of 343 individuals (3497 when U. imbuta and U. fastigiata are included) representing 54 species, belonging to 31 genera and 10 families (8 Anisoptera, 2 Zygoptera, see Appendix I). Two species could not be identified to genus level and are classified as Unknown species A and B. A total of 39 species were recorded during the surveys and an additional 15 were found on other occasions. Two families stand out for having both the most genera and species: Libellulidae and Coenagrionidae (Figure 2). The two families combined comprise ~ 73% of the species found in the area. A B Figure 2: Distribution of genera (A) and species (B) among the families found on Osa Conservation’s land.
Species distribution patterns For the 49 species that could be identified to species level, the broad distribution patterns on the North and South American continents were analyzed based on Esquivel (2006) (Table 1). The majority of the species found are widespread in Central and South America (57.1%) followed by species that are widespread in North, Central and South America (24.5%). 10.2% of the species only occurs in Central America and 4.1% is confined to the Nicaragua- Costa Rica-Panama region. No species endemic to Costa Rica were found. A small number of species are primarily South American species whose northern limit is Costa Rica. A similar small number of species is common in both North and Central America. One species, Telebasis Boomsmae was described from Mexico and Belize but was encountered on several occasions. Table 1: Distribution patterns of odonata found in the study area. Between site comparisons Species accumulation curves Species accumulation curves based on Chao 2 and first order jackknife estimates of species richness are plotted together with a Coleman curve and the observed species richness (Figure 3). Sample order was randomized 50 times in order to smoothen out the curves by reducing the influence of sample order. None of the species accumulation curves shown below have reached an absolute asymptote indicating that not all species present as the sites were found during the surveys. Piro trail appears to be the site that was sampled most successfully whereas many new species await discovery in Ocelotte stream and the swamp. Because of the lack of an asymptote, it is not possible to say how many more species are yet to be discovered For all but two sites (Piro river and the Swamp) the two estimators are fairly consistent in their estimates of species richness. For the two sites with the highest number of observed species (Piro river and the Swamp) the estimators overestimate the species richness when compared to the actual observed number of species. Species Percentage (%) Middle and South America 28 57.1 Widespread 12 24.5 Primarily Middle America 5 10.2 Nicaragua, Costa Rica and Panama only 2 4.1 Primarily South America 1 2.0 North and Middle America 1 2.0 Costa Rica only 0 0.0
Page 1 and 2: Odonata of the Osa Peninsula Brenda
Page 3 and 4: Site description Even though Costa
Page 5: Methods To account for both seasona
Page 9 and 10: Abundance and Richness Comparisons
Page 11 and 12: Discussion 268 species of Odonata h
Page 13 and 14: Appendix I: Odonata Species checkli
Page 15 and 16: Appendix II: Phenology of Odonata o
Page 17 and 18: Appendix III: Odonata of the Osa Pe
Page 19 and 20: Leptobasis vacillans ♂ © W.A. Ha
Page 21 and 22: Protoneura sulfurata ♂ Protoneura
Page 23 and 24: Erythemis vesiculosa ♂ Erythemis
Page 25 and 26: Orthemis schmidti ♂ Unknown speci

Odonata of the Osa Peninsula - Frontier

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