Philometra genypteri		Contents		Rev 10/31/2023
		Classification		Biology and Ecology
		Morphology and Anatomy		Life Cycle
Return to Philometra Menu				Ecosystem Functions and Services
		Distribution		Management
Return to Philometridae Menu		Feeding		References
		Go to Nemaplex Main Menu		Go to Dictionary of Terminology

Classification:

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Morphology and Anatomy:

With general characteristics of the genus Philometra. 

Philometra genypteri  differs from most other gonad-infecting Philometra spp. in:

• the length of spicules (126-135 um),
• the gubernaculum with dorsal lamella-like structures on its distal end.
• the number and arrangement of genital papillae in the male.
• some morphological and biometrical features of gravid female (absence of caudal projections, length of first-stage larvae or  moderately-developed anterior esophageal inflation)
• and by the fish family host type: the first philometrid species reported from a fish of the order Ophidiiformes
• and geographical distribution.: the second nominal species of Philometra recorded from marine fishes of the eastern South Pacific Ocean.

Philometra genypteri A anterior end gravid female, lateral view; B,C cephalic end of subgravid female, lateral and apical views; D anterior end of nongravid female, lateral view; E,F cephalic end of male, lateral and apical views; G anterior end of male, lateral views; H.I  posterior end of male, lateral view; J posterior end of subgravid female, lateral view; K larva from uterus, lateral view; L esophago-intestinal junction of female; M caudal end of subgravid female, lateral view; N caudal end of male, apical view (figures from Moravec et al., 2011)
Males:    Of 29 species of Philometra parasitizing marine and brackish-water fish, only nine have dorsal llamella--like structures on the distal part of the gubernaculum.	Female:   Ref: Moravec et al., 2011
Reported median body size for this species (Length mm; width micrometers; weight micrograms) - Click:

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Distribution:

Described from males and females in the ovary of red cusk-eel, Genypterus chilensis (Guichenot) (Ophidiidae, Ophidiiformes), from the eastern South Pacific Ocean off the coast of northern Chile (Moravec et al., 2011).

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Feeding:

 Parasite of fish gonad.    

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Biology and Ecology:

Gonad-infecting species of Philometra  are widely distributed in marine fishes of the Atlantic, Indian, and Pacific Oceans, sometimes also occurring in brackish-water environments.

Of 90 fish examined, 11% wwere in fected with P. genyptera at a mean intensity of 14 nematodes per dish (Moravec et al., 2011).

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Life Cycle:

All philometrids are ovoviviparous and after fertilization, females become very large as first stage larvae fill their uteri. In fully gravid females the vulva and anus atrophy in most philometrid genera. The first stage juveniles are dispersed nhen the female body bursts in contact with water.(Moravec and de Buron, 2013).

Ecophysiological Parameters:

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Ecosystem Functions and Services:

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Management:

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References:

Moravec, F. and Justine, J-L. 2008. Some philometrid nematodes (Philometridae), including four new species of Philometra, from marine fishes off New Caledonia. Acta Parasitologica 53:369-381.

Moravec, F., de Buron, I.  2013. A synthesis of our current knowledge of philometrid nematodes, a  group of increasingly important  fish  parasites. Folia Parasitologica 60:81-101.

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Copyright © 1999 by Howard Ferris.
Revised: October 31, 2023.