2 KEY AND CHARACTERS 



New Genera 



Lip-region retractile; cephalic setae 4, rather obviously segmented Ptycholaimellus 116 



Lip-region non-retractile; cephalic setae 10, not obviously segmented Rhips 118 



Striae not altered laterally, or very little; cephalic setae 10 



Lips thin and flap-like; cephalic setae long and obviously segmented Trilepta 92 



Lips not thin or flap-like; cephalic setae shorter, not obviously segmented; 'f 

 Striae resolvable ; pharynx not subdivided ; onchus not spear-like ; no cervical setae . Rhips 118 

 Striae plain ; pharynx in distinct chambers ; onchus spear-like ; cerv. setae long . (Bolbella) 90 

 Structure of the amphids spiral, circular, or elliptical 



Form of the amphids more or less distinctly spiral; spinneret present, doubtful in Laimella 

 Striae altered on the lateral fields; cephalic setae 4 



Wings present; striae fine, resolvable; lips 6, confluent, bipapillate; -f- Pepsonema 77 



Wingless; tooth with apophysis faintly y-shaped; striae coarse; amphids labial. . Ypsilon 96 

 Striae not altered on the lateral fields 



Onchus one, with its apophysis somewhat y-shaped; striae coarse; setae 4 Ypsilon 96 



Onchus not y-shaped, often with small companions 

 Amphids distinctly spiral 

 Setae 0; body striated (exc. head); pharyn. bulb faint, cardiac napiform. .Amphispira 103 



Setae, cephalic 10, subcephalic 4; non-striated; -f-; onchus spear-like (Laimella) 44 



Amphids appearing circular 



Lips 12-fold; onchus somewhat spear-like; cephalic setae small, 6 plus 10-12. .Mesodorus 105 

 Lips faint, not over 6; onchus not spear-like 



Ovaries -f-; phar. bulbous; amphids circular (?); setae 6 + 6; striae fine . (Bolbolaimus) 100 

 Ovaries reflexed, 'f 



Striae fine, plain; onchuli minute; lips faint, 6; papillae conical; setae 4. . (Polysigma) 106 

 Striae coarse; head not striated; cuticle thick; cephalic setae fasciculate. .Xanthodora 98 

 Form of the amphids circular or elliptical 

 Striae altered on the lateral fields; spinneret present 



Wingless; labial amphids elliptic; striae resolvable; pharyngeal bulb one-sided. lotadorus 115 

 Wings present; striae coarse 



Female sexual organs single, -f ; cephalic setae 4, labial setae 6; wings numerous. .Nudora 113 

 Female sexual organs double, 'f 



Head expanded, naked; striae not retrorse; tooth small; lips minute, obscure . Xenonema 102 

 Head not expanded, its setae 4 ; lips obvious; striae appar. retrorse throughout. Rhinema 114 

 Striae not altered on the lateral fields 

 Cephalic setae none 



Head hemispher . , expanded ; lips 6 , conoid ; spinneret pres . ; onchus obscure . (M icromicron) 104 

 Head not expanded; lips set off, confluent; no spinneret; 'f ; "spear" bent. . (Campydora) 88 

 Cephalic setae and spinneret present 



Onchus spear-like; amphids resemble concentric circles; setae in 2-3 rows (Mesodorus) 105 



Onchus not spear-like; amphids not concentric circles; setae, if numerous, fascicled 

 Female sexual organs outstretched 



Ovaries two; cephalic setae 6+6; submedian onchia present (Bolbolaimus) 100 



Ovary single; ceph. setae 4; submed. onchia none or vestigial Synonema 110 



Female sexual organs reflexed, 'f; amphids really spiral 



Submedian onchi present; labial papillae conical; setae 4; striae fine (Polysigma) 106 



Submedian onchi abs.; setae in fascicles; head non-striated; cuticle thick . (Xanthodora) 98 

 Oesophagus plain, i.e. without median or posterior bulb or swelling; amphids present 

 Form of the amphids more or less irregular, usually symmetrical to at least one line 

 The amphids linear; spinneret present; 'f; striae coarse, altered laterally 



Striae plain; head naked, set off by constriction; wing 1, prom.; cuticle thick. .Actinonema 117 

 Striae resolvable into rods; ceph. setae 10; wingless; amphid 5-6 times as wide as long. Rhips 118 

 The amphids not linear; striae not altered on the lateral fields 



Head conoid; cheeks thick; ocellate; onchus minute; phar. narrow; setae 10 (Isonemella) 109 



Head not conoid; cuticle of the cheeks not thick; 'f; striae fine, plain 



Spinneret absent; lips 6, unipapillate; cephalic setae 6; amphid behind pharynx . Onchulus 94 

 Spinneret present 



Buccal cavity extending beyond the nerve-ring; onchus spear-like; ocellate. Catalaimus 89 

 Buc. cavity not unusually long, its dors, element bent at lips; not ocellate. Asymmetrella 70 

 Form of the amphids spiral, circular, or elliptical 



The shape of the amphids a more or less distinct spiral ; spinneret present ; ' f ' or -f 

 Striae altered laterally, fine, resolvable; wings present; cephalic setae 10; 'f. .Acanthonchus 101 

 Striae not altered on the lateral fields, coarse, plain 



Spinneret unknown, abs. (?); -f ; setae 10; onchi submedian ; contour crenate. .(Gonionchus) 97 

 Spinneret present; T 



Lips three; setae 6; amphids labial; onchus digitate Digitonchus 95 



Lips more than 3 ; setae num . , scattered ; amphids not lab . ; onchi more than 1 . (Croconema) 112 

 The shape of the amphids circular or elliptical 



Striae altered laterally; wings numerous with retroree bristles; cephalic setae 4.. Rhinema 114 

 Striae not altered on the lateral fields 

 Head conoid; cephalic setae 10; spinneret present 



Ocelli none; 'f; rear portion of oesoph. succession of bulbs; striae fine, plain. (Bolbella) 90 

 Ocelli present; no succession of bulbs in the posterior part of the oesophagus 

 Cheeks thick; onchus appressed, minute; pharynx rather long and narrrow . (Isonemella) 109 

 Cheeks not thick; onchus digitate, well developed ;pharynx not narrow, short . Cophonchus 108 

 Head not conoid; not ocellate; pharynx not long and narrow 



Spinneret unknown; amphids spiral; -f ; setae 10; onchi submed.; contour cren. (Gonionchus) 97 

 Spinneret present 



Onchi 3, clustered; phar. unobv.; setae scattered; cuticle thick ; contour cien.. (Croconema) 112 

 Onchus single, dorsal; -f ; cuticle thin 



Setae 4; pharynx small, closed; diameter of amphid J the width of the head. . Synonema 110 

 Setae in 2s and 3s; phar. obv., open; diam. of amphid about i width of head. Anticyclus 111 



