domingo, 28 de agosto de 2011

A geometrical approach to know the distributional pattern/structure of the neotropical species of Staphylinidae: Plochionocerus Dejean & Agrodes Nordmann.

Daniel Felipe Silva Tavera


The beetles species of the genus Plochionocerus, and Agrodes, have been recently subjected of phylogenetic and Biogeographic analysis[1][2]. The species of these genus have caracteristic large body size and metallic colorations; as a result of their systematic revision, several synonyms were detected, mainly for species of Plochionocerus, which currently comprise 18 species and Agrodes with 2 species[1]. a Track analysis of these sister taxa were implemented using the Croizat`s manual reconstruction[2]. Three generalized tracks were identified from 15 individual tracks. This track analysis provides further species supporting the primary biogeographic homology of the 3 detected generalized tracks, which correspond to 3 major biotic components. Two of the generalized tracks are in the Caribbean subregion and a third in the Amazonian subregion[3]. In order to avoid the ambiguity and the subjective factor that lies on the traditional track analysis[4], in this opportunity is implemented a geometrical approach to know the distributional pattern/structure of the species of Plochionocerus & Agrodes, and answer the question: Are the generalized tracks representing the general patterns of distribution in the neotropical species of Plochionocerus and Agrodes?.

The distributional information of 13 of 18 Plochionocerus species and the 2 species of Agrodes are considered here. 279 record were used for build the input file with the distributional data, to be used on MartiTracks[4]. 38 of these records come of GBIF(accessed through GBIF data portal, Entomology Collection,, 2 records from CENTO-UIS, the rest from the revision work of ASIAIN et al in 2007 and Herman Lee in 2001[5]. The parameters values implemented are show in the commands1.txt file(below).

Results & Discussion

From 14 original (individual) tracks, were proposed the hipotesis primary of biogeographic homology, represented by 6 generalized track(fig 1). four are in the Amazonic subregion and two are in the Caribbean subregion (1 on the mesoamerican domain and the other in the Northeast South American domain). the 4 amazonic generaliced tracks are based on the individual tracks of A. conicicollis, A. elegans, P. janthinus, P. igneus, P.fulgens, P.splendens and the 2 Caribbean generalized tracks are based on the individual tracks of P.discedens, P.simplicicollis, P.ashei, P.humeralis, P.impressipennis, P.marquezi, P.puncticeps, A. elegans. The geographical distribution of P.newtonorum and P.pronotalis does not coincide with any of the generalized tracks obtained. From my geometrical approach to know the distributional pattern of these staphylinids , the hipotesis primary of homology biogeographic shown by Asiain et al (3 general tracks), is reevaluated, considerating the six general tracks proposed above. Nine species have been recorded exclusively from South America, 2 exclusively from Central America and 4 are shared between both areas. However, these results allow corroboration of previous biogeographic hypotheses about the mesoamerican and southamerican tracks from other component of the staphylinid biota[6].

The implementation of a geometrical tool represent an unambiguous pangiogeographic approach to know the distributional pattern of these taxa.

[1] Asiain, J., J. Márquez and J. J. Morrone. 2007. Phylogenetic systematics of the genera Plochionocerus Dejean and Agrodes Nordmann (Coleoptera: Staphylinidae: Xantholinini).
Zootaxa 1584:1-53

[2] Asiain, J., J. Márquez and J. J. Morrone.2010. Track analysis of the species of Agrodes and Plochionocerus (Coleoptera:Staphylinidae). Revista Mexicana de Biodiversidad 81: 177- 181, 2010

[3] Morrone, J. J. 2006. Biogeographic areas and transition zones of Latin America and the Caribbean islands based on panbiogeographic and cladistic analyses of the entomofauna.
Annual Review of Entomology 51:467-494.

[4] Echeverría-Londoño, S. & Miranda-Esquivel, D. R.2011. MartiTracks: a geometrical approach for identifying geographical patterns of distribution. PLoS ONE, 6(4), 0018460

[5] Herman, L.2001. Catalog of the Staphylinidae (Insecta: Coleoptera). 1758 to the end of the second millennium. VI. Staphylinine Group (Part 3). Staphylininae: Staphylinini (Quediina, Staphylinina, Tanygnathinina, Xanthopygina), Xantholinini. Staphylinidae Incerta Sedis Fossils, Protactinae. Bulletin of the American Museum of Natural History,
265, 3021–3840.

[6] Márquez, J. and J. J. Morrone. 2003. Análisis panbiogeográfico de las especies de Heterolinus y Homalolinus (Coleoptera, Staphylinidae, Xantholinini). Acta Zoológica Mexicana (nueva serie) 90:15-25


sset cv 0.25
set lmin 0.5
set lmax 0.75
set maxline 1
set ci 0.8

wine mt05-win32.exe test1.dat test1.dat.kml commands1.txt