Three new species of Huffmanela Moravec, 1987 (Nematoda: Trichosomoididae) from the gills of marine fish off New Caledonia

Three new species of Huffmanela, here described from eggs only, are reported from the gills of marine fish caught off Noumea, New Caledonia. Eggs of Huffmanela branchialis n. sp., from Nemipterus furcosus (Nemipteridae), are 45-52 (mean 48) mum in length and 23-30 (mean 25) mum in width, with thin shells. Each egg is enclosed in a thin membrane forming a spindle-shaped envelope 53-85 (mean 63) mum in length. Eggs of H. filamentosa n. sp., from Gymnocranius grandoculis (Lethrinidae), are 48- 53 (mean 50) mum in length and 25- 30 (mean 27) mum in width, with thin shells. Each egg bears a few long (150 mum), thin filaments. Eggs of these two new species were compared to those of H. paronai Moravec & Garibaldi, 2000, which are redescribed. Eggs of H. ossicola n. sp. were found within the branchial arch bone of Bodianus loxozonus (Labridae) and also filled the spinal chord bone and other bones. This is the first species of Huffmanela reported from bone tissue. Eggs are large, 72-88 (mean 79) mum in length and 32-40 (mean 36) mum in width, with a very thick shell. Each egg is covered with numerous filaments enclosed in a thin envelope. Fresh eggs were unembryonated, but embryos were visible after incubation in seawater. The three new species can be distinguished from other species of Huffmanela by size and the nature of the egg covering. Egg morphology of and their location in the host suggest different life-cycles: those of the first two species (small eggs, thin shells, egg covering possibly favouring flotation) are released from the gill mucosa with the turnover of living tissues and immediately continue their life-cycle, but eggs of H. ossicola (large eggs, thick shell) are only available for the continuation of the life-cycle after the host's death.