The life cycle of Huffmanela huffmani Moravec, 1987(Nematoda: Trichosomoididae), an endemic marine-relict parasite of Centrarchidae from a Central Texas spring

Abstract

Abstract:The life cycle of the swim bladder nematode Huffmanela huffmani Moravec, 1987 (Trichinelloidea: Trichosomoididae), an endemic parasite of centrarchid fishes in the upper spring run of the San Marcos River in Hays County, Texas, USA, was experimentally completed. The amphipods Hyalella cf. azteca (Saussure), Hyalella sp. and Gammarus sp. were successfully infected with larvated eggs of Huffmanela huffmani. After ingestion of eggs of H. huffmani by experimental amphipods, the first-stage larvae hatch from their eggshells and penetrate through the digestive tract to the hemocoel of the amphipod. Within about 5 days in the hemocoel of the experimental amphipods at 22 °C, the larvae presumably attained the second larval stage and were infective for the experimental centrarchid definitive hosts, Lepomis spp. The minimum incubation period before adult nematodes began laying eggs in the swim bladders of the definitive hosts was found to be about 7.5 months at 22 °C. This is the first experimentally completed life cycle within the Huffmanelinae.

Huffmanela lusitana sp. n. (Nematoda: Trichosomoididae) infecting pouting, Trisopterus luscus (Teleostei: Gadidae) off the Atlantic coast of Portugal

“…If the timings in the life cycle of H. lusitana sp. n. are similar to those revealed by Worsham et al (2016) for H. huffmani , then the initial infection event of a pouting would be followed by a year or more of the larvae and adult worms wandering through the musculature of the fish before there are enough dark eggs to detect macroscopically using standard inspection protocols. Such fish in early stages of infection might not be rejected by the consumer preparing the fish for consumption, but the histological damage done by the worms migrating in and out of the muscle cells could conceivably cause the fish to be rejected on the dish due to unexpected irregularities in texture.…”

“…Given that each species of Huffmanela deposits its eggs in a specific organ of the host (Worsham et al, 2016) and considering egg size, superficial envelope characteristics, host taxa and localities of 20 nominal species (Ruiz et al, 2013; Ruiz and Bullard, 2013; Justine and Iwaki, 2014), only four are known to infect the musculature. These are (with reported egg length and width, host taxonomy, and localities): H .…”

“…This is probably the result of mixing of different generations of eggs, due to repeated migration of several females through the same path at different tissues (Bullard et al, 2012). Since the tenure of a laying Huffmanela female is apparently ephemeral (Worsham et al, 2016), the observed mixing of eggs of obviously differing ages is probably indicative of separate infection events.…”

“…Little is known about the life-cycles of Huffmanela spp., although the life cycle of the only reported freshwater species, Huffmanela huffmani Moravec (1987), was experimentally completed by Worsham et al (2016). Apparently, the life-cycle of Huffmanela species infecting internal organs may require passage through the digestive tract of a predatory fish (or death and decay of the host) before they can infect the intermediate host.…”

Huffmanela sp. (Nematoda: Trichosomoididae: Huffmanelinae) encountered in the whitecheek shark (Carcharhinus dussumieri) in the Arabian Gulf

“…are nematode parasites affecting elasmobranch species, including sharks (Pollerspöck, 2012). The genus Huffmanela Moravec, 1987 comprises 21 valid species (Ruiz & Bul-lard, 2013;Ruiz et al, 2013;Justine & Iwaki, 2014;Ramos et al, 2019), diagnosed by the size and shape of their eggs, taking into consideration host range and site of infection (Bullard et al, 2012;Ruiz et al, 2013;Justine & Iwaki, 2014;Attia et al, 2021). This histozoic nema tode deposits its eggs in specifi c organs, induc-ing characteristic pathological lesions, easily seen with the naked eye (Moravec et al, 1998;Moravec & Garibaldi, 2000;Bullard et al, 2012).…”