RESUMEN
The myrmicine species Crematogaster rothneyi is one of the most widely distributed ants in Asia, but it has rarely been collected in the field. Its distribution range covers South and Southeast Asia, extending approximately 5,000 km from India in the west to Sulawesi in the east. Despite this wide distribution range, C. rothneyi has been treated as a single taxonomic species, and no combined morphological or molecular analysis has been conducted to assess whether any intraspecific variation exists. The sequence divergences of C. rothneyi populations, mainly obtained from Southeast Asia, were investigated by analyzing 387 bp and 175 bp sequences of the 12S ribosomal RNA and cytochrome c oxidase subunit (COI) genes, respectively. Phylogenetic analysis indicated that the C. rothneyi populations were separated into three groups: group I from Thailand and Cambodia, group II from Bangladesh and Myanmar, and group III from Krakatau and Sulawesi. Groups II and III were recovered as a single clade, sister to group I. The interspecific divergences were 7.3% to 8.5% for 12S and 14.5% to 23.3% for COI between most C. rothneyi specimens and Cambodian specimens, while divergence for 12S was 3.5% between Thai and Cambodian specimens. The Thai specimens are not morphologically differentiated, and are considered conspecific to C. rothneyi. We describe the Cambodian series as a new species, Crematogaster yaharai sp. nov., based on unique antennal morphology and mesosomal sculpture patterns with molecular evidence. Crematogaster rothneyi civa Forel, 1902 is synonymized under C. rothneyi. Crematogaster rothneyi is widespread and has sister species, suggesting recent diversification within the Indochinese Peninsula.
RESUMEN
The molecular phylogeny of 24 Oecophylla smaragdina populations and two O. longinoda populations was studied using 647 bp of the mitochondrial cyt b gene. The phylogenetic analysis suggested that O. smaragdina and O. longinoda were separated from each other first, and after that the first within-species divergence of O. smaragdina occurred in early stage of their history, in which the Asian, Australian, and Sulawesian groups rose. This grouping was almost coincident with the distribution of landmass in glacial periods in Pleistocene. Thereafter, each group seemed to have independently diverged into present populations on each landmass.
Asunto(s)
Hormigas/genética , Evolución Molecular , Filogenia , Animales , Hormigas/clasificación , Asia , Australia , Grupo Citocromo b/genética , ADN Mitocondrial/genética , Genes de Insecto/genética , Variación Genética , Especificidad de la EspecieRESUMEN
Crematogaster fraxatrix Forel, 1911 and two new species, C. chhangi sp. n. and C. simboloni sp. n., are described from Cambodia and Indonesia, respectively. DNA sequences were generated for C. fraxarix and the two newly described species using 3 amplications of two regions of the mitochondrial gene COI with a total of 1129 bp. The mean interspecific divergences are 9.4% and 23.5% for C. fraxatrix vs. C. chhangi, C. simboloni, respectively. DNA sequences reveal that C. simboloni is found to be genetically distinct from the other two species, but C. chhangi is not distinct from C. fraxatrix.
RESUMEN
To understand the complex relationships that exist between ant assemblages and their habitats, we performed a self-organizing map (SOM) analysis to clarify the interactions among ant diversity, spatial distribution, and land use types in Fukuoka City, Japan. A total of 52 species from 12 study sites with nine land use types were collected from 1998 to 2012. A SOM was used to classify the collected data into three clusters based on the similarities between the ant communities. Consequently, each cluster reflected both the species composition and habitat characteristics in the study area. A detrended correspondence analysis (DCA) corroborated these findings, but removal of unique and duplicate species from the dataset in order to avoid sampling errors had a marked effect on the results; specifically, the clusters produced by DCA before and after the exclusion of specific data points were very different, while the clusters produced by the SOM were consistent. In addition, while the indicator value associated with SOMs clearly illustrated the importance of individual species in each cluster, the DCA scatterplot generated for species was not clear. The results suggested that SOM analysis was better suited for understanding the relationships between ant communities and species and habitat characteristics.