Schistonchus aureus n. sp. and S. laevigatus n. sp. (Aphelenchoididae): Associates of Native Floridian Ficus spp. and Their Pegoscapus Pollinators (Agaonidae)

Nicole Decrappeo

Abstract


Two new species of Schistonchus were recovered from the hemocoel of adult female fig wasps, Pegoscapus spp. (Agaonidae), and the syconia of Ficus spp. native to Florida. They are described here as Schistonchus aureus n. sp., associated with Pegoscapus mexicanus and Ficus aurea, and Schistonchus laevigatus n. sp., associated with Pegoscapus sp. and Ficus laevigata. The Florida species of Schistonchus are differentiated from each other by host plant and fig wasp associates, number of incisures in the lateral field, male spicule shape, and mucronate male tail of S. aureus n. sp. Schistonchus aureus n. sp. and S. laevigatus n. sp. are differentiated from other members of the genus by the absence of a lip sector disc as observed with scanning electron microscopy for comparison with S. caprifici and S. macrophylla. Excretory pore position for both Florida species, S. altermacrophylla, and S. africanus is less than 50% (one half) the distance between the top of the head and the top of the metacorpus, as opposed to other species (S. caprifici, S. hispida, S. macrophylla, and S. racemosa), where it is located near or below the level of the metacorpus. Males of both species from Florida can be distinguished from S. altermacrophylla and S. africanus by the more posteriad positioning of the three pairs of caudal papillae; the anteriormost pair of papillae in the Florida species are adcloacal vs. precloacal in the other two species.

Keywords


agaonidae; aphelenchoididae; ficus; fig; nematode; new species; parasitism; pegoscapus; phoresy; scanning electron microscopy; schistonchus aureus n. sp.; schistonchus laevigatus n. sp.; taxonomy

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