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    Heterorhabditis floridensis n. sp (Rhabditida: Heterorhabditidae) from Florida
    (Magnolia Press, 2006) Nguyen, KB; Gozel, U; Köppenhöfer, HS; Adams, BJ
    In a survey of entomopathogenic nematodes associated with plants and trees in areas adjacent to production citrus groves in Florida, a new species of nematode in the genus Heterorhabditis was found based of morphological and molecular studies. The new nematode is described as Heterorhabditis floridensis n. sp. H. floridensis n. sp. is characterized by males, females, and infective juveniles. For males, the number of papillae in the terminal group of bursa is variable, either with 2 pairs of papillae (40%), with 3 papillae on one side and 2 papillae on the other side (30%), with one pair of papillae (20%), or with three pairs of papillae (10%). SW and GS values are 179 and 50, respectively. Females have a typical vulva pattern, which is different from that of closely related nematode species H. bacteriophora, H. mexicana, and H. indica. For infective juveniles, EP=109 (101-122) mu m, ES=135 (123-142) mu m, tail length = 103 (91-113) mu m, and a=27.6 (25-32) are different from those of the above-mentioned three related nematodes. Phylogenetic analysis based on ITS regions show that the new species forms a clade with H. mexicana, H. baujardi and H. indica and differs from these species by several nucleotide autapomorphies.
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    Steinernema yirgalemense n. sp (Rhabditida:Steinernematidae) from Ethiopia
    (Brill, 2004) Nguyen, KB; Tesfamariam, M; Gozel, U; Gaugler, R; Adams, BJ
    Steinernema yirgalemense, a new species based on morphological and molecular data, is described from Yirgalem, Ethiopia. This nematode belongs to the 'bicornutum-group' which includes nematodes with horn-like structures in the labial region of the infective juvenile. The new species can be recognised by the infective juvenile having a body length of 635 (578-693) mu m, distance from anterior and to excretory pore of 51 (45-59) mu m; tail length of 62 (57-67) mu m and E% (EP/tail length x 100) of 83 (67-90). The lateral field pattern is variable from anterior to posterior; the formula for the arrangement of ridges from head to tail being: 2, 6, 8, 6, 2. The new species can be further recognised by male characters: spicule with large velum and tapering posteriorly to a point, the ratio SW (spicule length/cloacal body diameter) and GS (gubernaculum length/spicule length) and especially by the presence of 12 pairs of genital papillae plus a single midventral papilla. The 12(th) pair, located at the edge of the cloacal aperture, is an important character. The presence of a low epiptygma is another diagnostic character of the new species. The new species is a sister taxon to S. abbasi and is characterised by the sequence length of the ITS regions (960 bp), ITS 1 (270 bp), ITS2 (284 bp) and also by the pairwise distance of both ITS and D2/D3 regions between species of nematodes in the 'bicornutum-group'.