Parasitodiplogaster species associated with Pharmacosycea figs in Panama

Parasitodiplogaster species that are associated with figs in the Ficus subsection Pharmacosycea, i.e., Ficus maxima, F. yoponensis, F. insipida and F. glabrata, were studied using morphological characters and molecular sequences. Some nematodes isolated from the fig sycones were casually observed and recorded as morphospecies according to their morphotype, and were then digested for their DNA, while others were fixed in formalin-glycerin for additional morphological study. High resolution microscopic observation of the morphological materials yielded five morphospecies including two nominal species, P. maxinema and P. pharmaconema. The morphospecies were distinguished from each other by male tail characters. By contrast, five and six genotypes were recognised by D2/D3 expansion segments of the large subunit (LSU) and near-full-length sequences of small subunit (SSU) ribosomal RNA genes, respectively. Except for two nominal species, genotypes and morphospecies were not clearly correlated because of limitations in the microscopic resolution in the initial morphotyping. Although the morphospecies and genotypes were not clearly paired, Pharmacosycea-associated Parasitodiplogaster species, which are tentatively referred to as the ‘P. maxinema group’, formed a monophyletic clade in both D2/D3 LSU and SSU analyses and are morphologically characterised by their stomatal morphology, i.e., a tube-shaped stoma with two stick-like teeth and male tail morphology, presence of nine paired papillae and relatively slender spicule.