Macfadyenia filicaudata, Allgén, 1953

Allgén, C. A., 1953, Terrestrial nematodes from Jan Mayen, Annals and Magazine of Natural History 12 (6), pp. 665-688 : 675

Macfadyenia filicaudata , sp. n.

(Fig. 5.)

Dimensions.—Body-length= 1.088 mm., max. width = 0.0 4 0 mm., oesophagus= 0.090 mm., tail=0.3 0 0 mm., vulva= 0. 4 5 2 mm., α = 2 7. 2, β =1 2.0 9, y = 3.63, V = 41.54 per cent.

The body is, on the whole, of even thickness and tapers almost imperceptibly in the oesophageal region and posteriorly up to the anus.

The cuticle is thin and smooth. The head is rounded, a t the front end provided with sublaterally situated, fine bristles.

The buccal cavity is supported a t the front end b y eight ribs and armed with a v e r y large, transversely situated, irregularly shaped, dorsal tooth, the point o f which is directed forwards. Opposite to this tooth there is also a smaller, acute, ventral tooth.

Lateral organs were not discernible. The oesophagus is short, strongly contracted, thick, with a large, oval, strongly muscular bulb.

The tail is elongated and tapers conically only in the foremost part and is very narrow for most o f its length, posteriorly rather gradually tapering, whip-like.

The vulva is situated in front o f the middle o f the body.

Female organs paired, with reflexed ovaries, the anterior ovary being bent dorsally, the posterior ovary ventrally.