a.s.l., could be composed of BVD-523 species that are also found in the Marañon valley. Indeed, several species

show distributions extending into this valley (e.g., Eriotheca discolor, Erythroxylum novogranatense, Loxopterygium huasango, Trichilia tomentosa, Clavija euerganea, Mauria heterophylla, Inga oerstediana). The altitudinal distribution of woody species and endemics showed two interesting relationships. In terms of absolute species numbers and endemics, the much more extensive coastal lowlands reported higher values than the sub-montane and mountainous areas. Nevertheless, once the effect of area had been taken into account by using the density of species per 1,000 km2, instead of absolute species PD-0332991 in vivo numbers, an opposite pattern

emerged, showing that species richness and endemics per unit area were highest in the mountains, and decreased substantially towards the lowlands. Similar results, although for greater elevational gradients (sea level to tree-line and above) and across several major vegetation types, were obtained by Borchsenius (1997) and van der Werff and Consiglio (2004) for the vascular floras of Ecuador and Peru, respectively. Both studies found that the density of endemic and restricted-range species was greater in the Andes than in the lowland areas on either side of these mountains. Furthermore, Borchsenius’ study suggested that the southern Andes, part of which is included in our study area, appeared to be particularly Z-VAD-FMK mouse rich in endemic species.

The geographical analysis by political units showed some interesting results. Loja, Cajamarca and Esmeraldas are the units where most vascular plants have been reported (with total vascular plant endemics highest in Cajamarca and Loja, Bracko and Zarucchi 1993; Jørgensen and León-Yánez 1999). In terms of woody SDF species, it seems that apart from Tumbes, Loja, El Oro and Cajamarca, the SDFs in the other regions appear to have been little collected. In addition, the high ratios of total vascular plants to woody SDF plants and of woody SDF endemics to total vascular plant endemics in Tumbes make this region probably the best representative of SDF vegetation in the study area. The geographical distribution analysis showed that a substantial amount Rho of the species, non-endemics (27.5%) and especially endemics (52.9–87.5%), have been reported in less than two provinces or departments. In some cases, this might be the result of little collecting (see below), but in the case of the endemic species, these are by definition restricted to a certain area and sometimes, within this area, they are rare and local. In the SDFs of the region, we face the severe problem of habitat destruction and some estimations consider that less than 5% of the area remains forested (BirdLife International 2003). The rarity of some species and habitat reduction potentially threatens the SDF.