The following items concerning dorylaimoidid nematodes are dealt with in this paper: a) A historical review of the superfamily Dorylaimoidea, from its establishment by THORNE in 1934 up to our present days. Cephalodorylaimidae (Jairajpuri, 1967) n. rank is removed to Encholaimoidea Golden & Murphy, 1967. Pungentinae is upraised to the family rank. Nordiidae is then restricted to one subfamily, Nordiinae. ANDRÁSSY's (1969) sub-families. Mesodorylaiminae, Afrodorylaiminae and Laimydorinae, together with Thornenematinae (Jairajpuri, 1969) n. rank, are taken as subdivision of Thornenematidae Jairajpuri, 1969. The genus Lenonchium because of acicular spear and similar male and female tails, is removed from Thornenematidae to Lenonchiidae n. fam. In addition, the genus Tyleptus having a quite different spear, is removed from Leptonchidae Thorne, 1939 to Tyleptidae (Jairajpuri, 1964) n. rank. Thus, 71 genera and 20 families are recognized in the superfamily Dorylaimoidea; b) Morphological notes concerning some features not discussed by LORDELLO (1965) in his study on the Brazilian nematodes of the family Dorylaimidae. In this chapter, terms and definitions recently dealt with by SIDDIQI (1969) are translated and introduced into the Brazilian nematological language; c) A key for separating families, subfamilies and genera; d) Emendations to the diagnosis of some families, and diagnosis for a new family proposed, as given belowg: 1. Family Thornenematidae Siddiqi, 1969 Diagnosis (emended): Dorylaimoidea. Moderate to large-sized (length over 1 mm). Polymyarian. Cuticle firm, regular, without longitudinal ridges, wrinkles or fixation folds. Lip region, spear, spear extension and oesophagus dorylaimid. Definite spear guiding ring present and walls of stoma not thickened. Oral opening and pharynx circular. Intestine polycytous. Ovaries paired or single. Female tail elongate-filiform; male tail short, usually rounded, sometimes conical. Spicules large, dorylaimid; lateral guiding pieces present. Male with numerous ventromedian supplementary papillae which are not grouped in fascicles. Type genus: Thornenema Andrássy, 1959. 2. Subfamily Thornenematinae (Siddiqi, 1969) n. rank. Diagnosis: Thornenematidae. Spear guiding ring single. Female gonad opisthodelphic and reflex. Male rare or unknown; when present, with conical tail with or without a short terminal knobed appendage. Supplements not very numerous (6-7), separated and with a gap to the adanal pair. Prerectum short. A single genus: Thornenema. 3. Family Nordiidae (Jairajpuri & A.H. Siddiqi, 1964) Siddiqi, 1969. Diagnosis (emended): Dorylaimoidea. Small-sized (length under 1 mm). Polymyarian. Cuticle firm, regular, moderately thickened, without radial striae. Body pores indistinct. Lip region amalgamated, continuous with or slightly offset from body by a depression, never by a constriction. Cephalic papillae not raised. Spear slender, elongate, with narrow lumen and aperture. Spear extension elongate without basal swellings or flanges. Oral opening, vestibule and pharynx narrow, circular, devoided of sclerotized pieces. Oesophagus muscular, enlarging behind the middle. Posterior pair of subventral oesophageal glands opening close to oesophageal base. Females didelphic or opisthodelphic. Vulva longitudinal or transverse. Tails in both sexes similar, short, conoid or hemispherical. Male with dorylaimoid spicules and non-contiguous ventromedian supplements. A single subfamilyi Nordiinae Jairajpuri & A. H. Siddiqi, 1964. Type genus: Longidorella Thorne, 1939. 4. Family Pungentidae (Siddiqi, 1969) n. rank Diagnosis (emended). Dorylaimoidea. Moderate-sized (length about 1 to 2 mm). Polymyarian. Cuticle firm, regular, moderately thickened with radial striae. Lip region offset by a depression from body; lips amalgamated; cephalic papillae usually raised. Spear strong (slender or thick, short or moderately elongate). Spear extension base with prominent basal swellings. Sclerotized pieces around entrance to vestibule usually present. Posterior part of oesophagus occupying last half or so. Posterior subventral oesophageal glands opening anterior to oesophageal base. Female gonad amphidelphic or opisthodelphic. Tails in both sexes similar, conoid rounded to hemispherical. Male with dorylaimoid spicules and separated ventromedian supplements. This family differs from Nordiidae in showing: a) stronger spear; b) spear extension base with prominent swellings; c) posterior subventral oesophageal glands opening anteriorly to oesophageal base; d) sclerotized pieces around entrance of vestibule; and, e) cuticle with radial striae. Type genus: Pungentus Thorne & Swanger, 1936. 5. Family Lenonchiidae n. fam. Diagnosis: Dorylaimoidea. Moderate sized (length about 2,0-2.5 mm). Polymyarian. Cuticle firm, regular, devoid of longitudinal ridges and with fine transverse striae. Lip region rounded, .continuous with body; cephalic papillae not raised. Spear acicular, slender, moderately elongate and with short aperture. Spear extension rod-like, slightly swollen at base. Spear guiding ring single. Oral opening and pharynx circular. Oesophagus dorylaimid, having more than half of its length enlarged. Intestine polycytous. Vulva transverse. Female gonads paired, opposed and reflexed. Males common, diorchic; sperms fusiform. Ventromedian series of supplements with numerous contiguous papillae with a short gap to adanal pair. Spicules large, dorilaimoid, with small lateral guiding pieces. Tails similar in both sexes, elongate-filiform. Male prerectum beginning at level of ventromedian series of supplements. This family is distinguished from Prodorylaimidae Andrássy, 1969, in having: a) acicular spear; b) spear extension base swollen; c) spear guiding ring single; and, d) ventromedian series of supplements not anterior from the spicules. Single and type genus: Lenonchium Siddiqi, 1965. 6. Family Leptonchidae Thorne, 1935. Diagnosis (emended). Dorylaimoidea. Small to moderate-sized (0.5 - 2.0 mm). Meromyarian. Cuticle loose, often with fixation folds and radial elements; its inner layer and sub-cuticle forming coarse transverse annules. Lip region angular deeply offset from body by constriction; lips amalgamated; cephalic papillae slightly prominent; inner circle of papillae sometimes appearing as an adoral cephalic disc. Spear very slender, delicate, with narrow lumen and small aperture. Spear extension arcuate, without basal knobs or flanges; vestibule a, truncate cone serving as a guiding ring. Oesophagus a slender non-muscular tube terminating in an oblong pyriform bulb devoiding of triquetrous valvular chamber. Intestine oligocytous. Excretory pore present. Lateral pores present. Female didelphic or monodelphic. Male diorchic. Spicules dorylaimoid; lateral guiding pieces present. Tails similar in both sexes, conical to hemispherical. Single subfamily: Leptonchinae Thorne, 1935. Type genus: Leptonchus Cobb, 1922. 7. Family Tyleptidae (Jairajpuri, 1964) n. rank. Diagnosis. Dorylaimoidea. Small-sized (under 1 mm). Meromyarian. Cuticle loose, often with fixatior folds and sometimes with radial elements, sometimes with transverse striae. Lip region rounded, offset from body by depression, usually with six distinct or amalgamated adoral liplets. Vestibule sclerotized. Spear moderately robust and wide, making with its "extension" a single piece from place of origin; "extension" straight. Spear guiding ring single. Oesophagus slender, non-muscular tube, with a pyriform basal bulb provide with a narrow, triquetrous valvular chamber in its posterior half. Excretory pare and lateral pores present. Vulva premedian (V under 45%). Female opisthodelphic. Tail similar in both sexes, hemispherical. Spicules dorilaimoid; lateral guiding pieces present. Supplements in small number, widely spaced. This family is distinguished from Leptonchidae in having: a) a different kind of spear extension; b) oesophageal basal bulb provided with valvular chamber; c) lip region rounded, usually with six prominent adoral liplets; and, d) opisthodelphic female. Single subfamily; Tyleptinae Jairajpuri, 1966. Single genus: Tyleptus Thorne, 1939. e) A list of the species of Dorylaimoidea recovered from some soil coffee plantations in the State of São Paulo, Brazil, with citation of the pertinent literature and synonyms. f) Description of some male alotypes, modification on the systematic position of some species, a redescription of one form and notes on morphology of all other species identified. 1 - The following male alotypes are described; 1) Thornenema cavalcantii. Resembling females on general morphology but showing a conical-rounded tail, prolongated in a short terminal process provide with a knobed tip. It has: a) ventromedian supplementary series with seven papillae in addition to the adanal pair; b) spicules dorylaimoid; c) lateral guiding pieces present; d) a single reflexed testis; and, e) four pairs of lateral pores on tail. 2) Chitwoodius transvaalensis. Similar to female on general morphology and showing: a) ventromedian supplementary series with 10 elements besides the adanal pair; b) five pairs of lateral pores on tail; c) spicules dorilaimoid; and, d) lateral guiding pieces present. 3) Leptonchus scintillans. Similar to the females on general morphology and having: a) ventromedian supplementary series with 4 or 5 papillae in addition to the adanal pair; b) spicules dorylaimoid and lateral guiding pieces as figured; and, c) tail as long as or slightly longer than·anal body diameter. 4) Aporcelaimellus coniocaudatus. Resembling females on general morphology and exhibiting: a) a ventromedian series with 6, 7 or 8 irregulary spaced supplements and with a gap to the adanal pair; b) spicules long, dorylaimoid, moderately curved; c) lateral guiding pieces almost straight, measuring 1/6 of spicules length; and, d) two pairs of papillae and 3 pairs of lateral pores on tail, as figured. 5) Scapidens perplexus. Similar to female on general morphology and having: a) two small ventromedian supplements located very far from the adanal pair; b) tail as long as anal body diameter and with 2 pairs of lateral papillae; c) spicules dorylaimoid; and, d) lateral guiding pieces as illustrated. 6) Eudorylaimus piracicabensis. Resembling females on general appearance and having: a) a ventromedian series with 18 irregularly spaced supplements, without a gap to the adanal pair; b) tail with 3 pair of lateral papillae; c) spicules dorylaimoid 1,5 times as long as tail; and, d) lateral guiding pieces as figured. II - Concerning the systematic position .of some species, the following items are dealt with: 1) Drepanodorylaimus picardi (Altherr, 1963) n. comb. (Andrássy). This new combination is to be ascribed to Andrássy. Actually in future papers, the authorship is to be cited as Andrássy in Monteiro, 1970. ANDRÁSSY (1969) pointed out the identity of Dorylaimus picardi Altherr, 1963 and Drepanodorylaimus filiformis Jairajpuri, 1966, without presenting the new combination. Dorylaimus filicaudatus sensu Williams, 1959, nec Daday, 1905, is considered a junior synonym of Drepanodorylaimus picardi. 2) Aporcelaimus krygeri (Ditlevsen, 1928) Brzeski, 1962. The transference of this species to Aporcelaimellus was proposed by HEYNS (1965). However, it is retained in Aporcelaimus, according to the following details: a) cuticle evently thickened, showing criss-cross lines and a thin and poorly defined outer layer; b) amphids divided and with a median suport; c) front part of pharynx appearing cross-shaped in a face view; d) vulva a long transverse slit with cuticularized lips; and, e) ventromedian cuticular pores occurring on entire length of body. 3) Aporcelaimellus coniocaudatus (Altherr, 1953) n. comb. This species fits better here than in Aporcelaimus to which it was transfered by HEYNS (1965). It .presents the following characteristics: a) cuticle thickened, mostly toward extremities and with fine transverse striae; b) vulva a small pore; c) amphids individed without median suport; and, d) front part of pharynx appearing hexagonal in a face view. 4) Discolaimium maracaiense (Lordello, 1965) n. comb. This species was described by LORDELLO (1965) as a member of Pungentus being here transfered to Discolaimium redescribed. The "structures" figured by LORDELLO and as sclerotized pieces in vestibule, proved to result from an optical illusion as previously reported by SIDDIQI (1969)·in Eudorylaimus australis (Yeates, 1967) Siddigi, 1969. Discolaimium maracaiense (Lordello, 1965) is a didelphic Discolaimium differing from all other previously described species in haying small dimensions. It differs from D. sublatum Heyns, 1963, which is its most closely resembling species, in showing: a) shorter body and small demanian values; b) shorter basal portion of oesophagus, c) almost straight body; and, d) longer prerectum. III - Among other notes on morphology of species recorded, the most interesting ones deal with Lordellonema bauruense. In this species, the subcuticle shows elevations like small calottes arranged in transverse lines. Such callottes are seen in an optic median view as characteristic ondulations, as described and figured by LORDELLO (1957). The scalelike structures reported by same author are also resulting from elevations of inner cuticular layer. In a superficial view those elevations appear as curved lines on the lateral fields (as well on dorsal and ventral fields depending on the position of the specimen), particularly on the posterior portion of body. Transverse section made at the anterior portion of body, showed that the cuticular inner layer invaginated along the lateral dorsal and ventral fields, as figured. In addition to the lateral and ventral pores seen by LORDELLO, the species also shows dorsal pores on neck region. g) Descriptions of 10 species as follows: 1) Longidorella perparvula n. sp. A didelphic Longidorella differing from all other previously described species by its very small dimensions. Males unknown. 2) Tylencholaimus leptodorus n. sp. A prodelphic species differing from T. leptonchoides Loof, 1964, in having: a) shorter tail (2.5 - 2.8 : 4 - 5 times the anal body diameter); b) shorter basal portion of oesophagus (28-29% : 36-40% of oesophagus length); c) longer prerectum (5-5 - 6.5 : 3.5 - 5.0 times the anal body diameter); and, d) shorter and thinner spear. Male unknown. 3) Tylencholaimus paracrassus n. sp. Closely resembling T. crassus Loof & Jairajpuri, 1968, from which it differs in having: a) slightly longer body (female length = 0.90 - 1.09 : 0.68 - 0.92 mm); b) tail proportionally longer; and, c) body curved ventrally (T. crassus shows a straight body). In this species, males are as common as female and have 3 ventromedian supplements in addition to the adanal pair. 4) Tyleptus affinis n. sp. This species resemble T. projectus Thorne, 1939, but differs in having: a) shorter body (female length = 0.48 g 1.00 mm); and, b) a different tail. Males have 2 ventromedian supplements in addition to the adanal pair. 5) Basirotyleptus xiphinemoides n. sp. In this species, the spear extension has a peculiar organization, resembling that found in Xiphinema spp. B. xiphinemoides most closely resembling species are B. coronatus Siddiqi & Khan, 1965 and B. modestus Husain & Khan, 1968. It differs from B. coronatus in having: a) shorter tail (female: c= 47.9 - 49.1 : 74 - 100); b) longer uterine sac; c) longer spear and longer spear extension; d) different organization of stoma; and, e) shorter amphids. It is distinguished from B. modestus in having: a) longer body (females length = 0.75 - 0.77 g 0.45 - 0.53 mm); b) spear shorter than spear extension (in B. modestus the spear is longer than spear extension); and, e) different organization of stoma. Males as common as females and showing two ventromedian supplements in addition to the adanal pair. 6) Discolaimus pizai n. sp. D. pizai most closely resembling species is D. affinis Loof, 1964, from which it differs in having: a) tail shorter than anal body diameter; b) about 120 glands in each lateral chord; and, c) lip region width greater than spear. Two males of D. pizai were found. One had a ventromedian series of 6 supplements, the 3 proximal ones being contiguous. The other male showed a ventromedian series of 11 supplements, the 5 proximal ones being contiguous. 7. Discolaimium hemidelphum n. sp. An opisthodelphic Discolaimium differing from D. monhystera Siddiqi, 1965 in having: a) smaller dimensions (length = 0.68 - 0.76 : 1.22 - 1.23 mm); b) longer spear (13 - 14 : 8 - 9 microns); c) vulva located closer to base of oesophagus (distance from base of oesophagus to vulva = 1/3 : 1 length of oesophagus); and, d) different shape and size of tail. Male unknown. 8. Crateronema lordelloi n. sp. C. lordelloi differs from C. aestivum Siddiqi, 1969, in having: a) shorter body (length = 0.65 - 0.68 : 1.06 - 1.25 mm); b) body less curved ventrally (C. aestivum has a strongly ventrally curved body); and, c) proportionally longer oesophagus (b = 3,1 - 3,3 : 4,2 - 4,4). Male unknown. 9. Amphidorylaimus flagellicauda n. sp. A. flagellicauda differs from A. infecundus (Cobb in Thorne & Swanger, 1936) Andrássy, 1960 in having: a) more attenuated body; b) proportionally longer tail (length of tail = 20 : 15 times anal body diameter); and, d) vulva located more anteriorly (V%= 34 - 36 : 39). Male unknown. 10. Labronema virgo n. sp. L. virgo most closely resembling species possibly is L. rikia Yeates, 1967, from which it differs in having: a) a little longer tail (c = 61 - 72 : 78 - 84); b) vulva located more anteriorly (V% = 49.8 - 52.3 : 56.3 - 58.8); and, c) shorter prerectum (1.3 - 2.0 : 2.0-3.0 times the anal body diameter). Male unknown.