Some New Brazilian Nematodes

Abstract

Body large and stout, attenuated anteriorly and posteriorly; cuticle with deeply transverse striations. Mouth with two large, simple, triangular, lateral lips, each armed with two external sessile papillae and one median, of thickness of cuticle; the lips bear internally two pairs of small chitinous teeth and are separated from the body by a cephalic collarette. Lateral symmetrical alae present in the anterior region of the body, beginning in the neck region and ending at the level of the cervical papillae. Male: The average length of the male specimens studied was about 25 mm., the maximum breadth being .8 mm. The oesophagus measures 3.2 mm. in the total length and consists of an anterior muscular and a posterior glandular part; the first portion is .5 mm. long. Cervical papillae located .9 mm. from the mouth aperture. The tail is sharply recurved ventrally, with large asymmetrical caudal alae supported by four pairs of pedunculated papillae, of which one is preanal, two adanal and one postanal. There are one unpaired, median sessile, preanal papilla and six pairs of sessile lateral papillae, one preanal and five postanal. The spicules are unequal in size and shape: the great one is pointed at the distal extremity and measures .46 mm. in length, the small one has a hooklike process near the pointed distal extremity and is .4 mm. long. The anogenital opening is situated .87 mm. from the tip of the tail. Female: The length of the mature specimens varies from 27 to 55 mm. and the breadth, 1 to 1.9 mm. The lips measure .08 mm. Oesophagus 3.8 to 5.4 mm. in total length, the muscular portion being .54 to 0.7 mm. long. Greatest width of oesophagus, .3 to .4 mm. Cervical papillae 1.2 mm. from the anterior end in the largest specimens. The vulva is situated near the posterior third of the body. The short, muscular vagina extends posteriorly and unites with the two uteri. Eggs thick-shelled, measuring .05 by .036 mm.