99 Philippine Journal of Systematic Biology Vol. V (June 2011) Short Notes OCCURRENCE OF CELLULAR SLIME MOLDS (DICTYOSTELIDS) IN SUBIC BAY NATURAL FOREST RESERVE, ZAMBALES, PHILIPPINES THOMAS EDISON E. DELA CRUZ 1,2* , KRYSTLE ANGELIQUE A. SANTIAGO 1 , CARLY SIMON P. RAMIREZ 1 , JEREMY MARTIN O. TORRES 1 , NIKKI HEHERSON A. DAGAMAC 1,3 , JENNIFER YAP 1 , MARICAR CHING 1,3 , AND PAUL RICHARD J. YULO 1 1 The Graduate School, and 2 Fungal Biodiversity and Systematics Group, Research Cluster for the Natural and Applied Sciences, University of Santo Tomas, España 1015 Manila, Philippines 3 Department of Biological Sciences, School of Science and Technology, Centro Escolar University, Mendiola 1009 Manila, Philippines Corresponding Author Email: tedelacruz@mnl.ust.edu.ph ABSTRACT Cellular slime molds or dictyostelids are unicellular, amoeboid organisms that feed on bacteria. They are commonly found in forest soils where they play an important role in maintaining balance among soil microbial flora. However, in the Philippines, in spite of their important ecological roles, very few studies have looked at these organisms. Thus, this present investigation was designed to look at the occurrence of cellular slime molds in two forest trails within Subic Bay Natural Forest Reserve, Zambales, Philippines. Forest and mossy soils were collected from these areas and used for the isolation of dictyostelids. Our results showed clonal population counts of 821 to 3,150 clones/g soil. Identification of the isolated dictyostelids showed two species: Dictyostelium laterosorum and Polysphondylium pallidum. This is the first report of cellular slime molds in Subic Bay Forest Reserve, Zambales. Keywords: clonal population count, Dictyostelium, diversity, forest soil, Polysphondylium Cellular slime molds or dictyostelids are phagotrophic bacterivores commonly isolated from forest soils found in different climate types around the world (Swanson et al., 1999). These organisms are abundant in the humus layer of forest soils that are rich in bacteria on which they feed (Cavender & Raper, 1965b). They are thought to play an important role in maintaining balance among microbial