Soil and litter nematode diversity of Mount Hamiguitan, the Philippines, with description of Bicirronema hamiguitanense n. sp. (Rhabditida: Bicirronematidae)

Abstract

The nematode diversity in soil and litter was investigated on Mount Hamiguitan, the Philippines, along four eco-habitats from elevations of 75-1600 m a.s.l. A total of 155 and 467 nematodes were identified to 39 and 62 genera from litter and soil, respectively. The nematode assemblages and diversity did not show any relation to eco-habitat or elevation. Bacterivorous nematodes were the most common group (37.5%). Acrobeloides was most abundant from the soil and Aphelenchoides from the litter. Bicirronema hamiguitanense n. sp. is herein described based on morphology, morphometrics and molecular data. The new species has the following diagnostic features: a wide lateral field one-fifth of its body diam. with four incisures forming two ornamented ridges; gubernaculum with proximal thickening; spicules (35-38 μm) and gubernaculum (18-20 μm) longer than B. caledoniense; and with 37 molecular autapomorphies supporting its new species status. The phylogenetic position of the new species within Cephalobomorpha is discussed.