Taxonomy, ecology and conservation of Phyllanthus erythrotrichus C.B.Rob. (Phyllanthaceae) in Zambales, Philippines

The study was conducted in Acoje Mine site of Sta. Cruz, Zambales, Philippines from November 2014 to March 2015. Generally, it aimed to update the taxonomy and ecology of the species. Specifically, it aimed to (a) characterize the morphology, anatomy, ecology and seedling architecture of P. erythrotrichus; and (b) recommend a conservation program for P. erythrotrichus specifically in Acoje mine site in Zambales, Philippines. To characterize the floristic composition and associated vegetation of the study site, two 10m x 10m quadrats in Sitio Guisguis and Sitio Pine tree in Acoje, Zambales were established. All plants with a diameter of greater than or equal to 1cm were permanently tagged and measured. Importance values of each species, diversity indices for each quadrat, endemic and threatened species in the area were determined. Herbarium studies were also conducted to compare morphological characteristics and validate all collections using quantitative blade lamina characters. Further, seedling architecture was also determined. Anatomical characterization of leaf, stem and roots were conducted using paraffin techniques in the Microtechnique laboratory at FBS-CFNR-UPLB [Forest Biological Science-College of Forestry and Natural Resources-University of the Philippines Los Baños]. Vegetative propagation was conducted to assess conservation measure (in situ or ex situ) for P. erythrotricus. A total of 244 individuals belonging to 42 tree species from 31 families were recorded from the two 10m x 10m quadrats. The stand density is from 0.10 to 0.46 tree/m sup 2; average number of trees is 28 for every 100 m sup 2 and the average diameter for all trees inside the quadrat is 1.52 cm. The three most important species (with the highest IV) are Desmodium quinquepetalum (45.99), Syzygium sp. (30.22) and Calophyllum pentapetallum (20.61). Both Sitio Guisguis and Sitio Pine tree quadrats had high diversity and have balance distribution of species and individuals. Morphologically, a few more detailed descriptions and new character traits have been added in this study. The phyllomorphic branch was newly described to consist to 18-27 small leaves on each side. Leaves are narrow oblong to lanceolate to falcate. In floral morphology, the ovary position and other pistilate parts is half-inferior. Its seedling architecture is common as epigeal. It has heteroblastic development of leaves and has phyllantoid branching. Anatomically, leaf anatomy is dorsiventral. It is where the adaxial epidermis is followd by palisade mesophyll cells, next is the palisade layer and abaxial epidermis. P. erythrotricus could be assigned to be Vulnerable (VU) category (Section 5 of RA 9147, and Section 1 of DAO No. 2004-15) due to increasing threat of extinction from mining activities. Further, the species can be propagated and conserved ex situ through stem cuttings. The detailed descriptions and new character traits have been added to the description of P. erythrotricus by means of morphological and anatomical analyses. However, the anatomical studies on the species are limited; therefore more comparative studies are needed.