Molecular phylogeny of the genus Saguinus (Platyrrhini, Primates) based on the ND1 mitochondrial gene and implications for conservation

The systematics of the subfamily Callitrichinae (Platyrrhini, Primates), a group of small monkeys from South America and Panama, remains an area of considerable discussion despite many investigations, there being continuing controversy over subgeneric taxonomic classifications based on morphological characters. The purpose of our research was to help elucidate the phylogenetic relationships within the monkey genus Saguinus (Callitrichinae) using a molecular approach to discover whether or not the two different sections containing hairy-faced and bare-faced species are monophyletic, whether Saguinus midas midas and Saguinus bicolor are more closely related than are S. midas midas and Saguinus midas niger, and if Saguinus fuscicollis melanoleucus and Saguinus fuscicollis weddelli really are different species. We sequenced the 957 bp ND1 mitochondrial gene of 21 Saguinus monkeys (belonging to six species and nine morphotypes) and one Cebus monkey (the outgroup) and constructed phylogenetic trees using maximum parsimony, neighbor joining, and maximum likelihood methods. The phylogenetic trees obtained divided the genus Saguinus into two groups, one containing the small-bodied species S. fuscicollis and the other, the large-bodied species S. mystax, S. leucopus, S. oedipus, S. midas, S. bicolor. The most derived taxa, S. midas and S. bicolor, grouped together, while S. fuscicollis melanoleucus and S. f. weddelli showed divergence values that did not support the division of these morphotypes into subspecies. On the other hand, S. midas individuals showed divergence compatible with the existence of three subspecies, two of them with the same morphotype as the subspecies S. midas niger. The results of our study suggest that there is at least one Saguinus subspecies that has not yet been described and that the conservation status of Saguinus species and subspecies should be carefully revised using modern molecular approaches.

Molecular studies of Callithrix pygmaea (Primates, Platyrrhini) based on transferrin intronic and ND1 regions: implications for taxonomy and conservation

As classificações tradicionais envolvendo os macacos da infraordem Platyrrhini, principalmente baseadas em características morfológicas, têm sido contestadas por dados moleculares recentes. A subfamília Callitrichinae (Platyrrhine, Primates) engloba um diverso grupo de espécies, muitas das quais consideradas em perigo de extinção. A presente análise de duas regiões do DNA, um gene mitocondrial (ND1) e um gene nuclear (regiões intrônicas da transferrina), sugerem que Callithrix pygmaea apresenta variabilidade suficiente para justificar a existência de subespécies ou até mesmo de espécies distintas. As árvores filogenéticas baseadas na região do ND1 indicam que esta espécie está relacionada mais proximamente aos marmosets amazônicos do que aos da mata Atlântica. Estes resultados reabrem a discussão sobre diversidade e programas de conservação baseados apenas em classificações taxonômicas tradicionais.