Rev 02/22/2024
Chromadorea Rhabditida Rhabditia Chambersiellidae
Diastolaimus Rahm, 1928
Taxonomic note:
Cid (2012) indicates a total of six species of Diastolaimus, Rahm, 1928. Of those, D. papillatus Rahm, 1928 and 1929 seems to have been moved to Macrolaimus by Goodey (1951) and then to Chambersiella by Sanwal (1960). The type species is indicated as D. croca (Massey, 1963) Andrassy, 1984. Other species include D. grossus (Truskova & Eroshenko, 1977) Andrassy, 1984, D. damalis (Massey, 1966) Andrassy, 1984, D. aculentus (Von Daday, 1905) Andrassy, 1984 and D. mexicana (Cid, 2012). Fescia grossa Truskova & Eroshenko, 1977 was transferred to Diastolaimus as D. grossus by Andrassy (1984)
Diastolaimus croca: A, B. Head (a) amphid aperture (s) sensilla pouch; C. Face view; D. Male tail; E. Female midbody; F. Female
Diastolaimus (Santafea) croca, from Massey, 1963
Cuticle .finely striated.
Lip tregion without cephalic cirri (elaborate projections).
Six prominent cephalic papillae;
Stoma similar to Chambersiella; Cheilorhabdions and protorhahdions distinct, the meso, -meta and telorhabdions fused into a glottid apparatus which extends well back into the precorpus of the esophagus. Amphid opening at the anterior 1/3- of the telostom. Corpus of -the esophagus without a bulb but set off by a slight swelling at its base; Isthmus swelling to a valvate, terminal bulb.
Tails in both sexes with a hooked terminus.
Female monovarial.Ovaries paired; vulva at midbody. Male monorchic, spicules, paired; gubernaculum present.Male tail with several pairs of: caudal papillae. Diastolaimus-is readily distinguishable from Chambersiella in the absence of cephalic cirri or hairlike setae.
Ref: Massey, 1963; Sanwal, 1971Type species: Diastolaimus croca
The type specimens were taken from the Sandia Mountains, Cibola National Forest, and the Otowi section of Bandelier National Monument in New Mexico.
They :were found associated with Scolytus ventralis Lee in Abies concolor (Gord. and Glend.) Lindl. and Phloeosinus sp. in Juniperus osteosperma (Torr.) Little.(Massey, 1963).
Bacterial feeder.
Nematodes in the Chambersiellidae are frequently reported in assocaiation with bark beetles. The relationships are probably phoretic in that the nematodes are transported from tree to tree or to insect galleries by the beetles.
Andrassy, I. 1984. Klasse Nematoda (Ordnungen Monhysterida, Desmocolecida, Araeolaimida, Chromadorida, Rhabditida) Bestimmungsbűcher zur Bodenfauna Europas, No.9. Berlin (Deutschland): Akademie Verlag.
Cid del Prado, V.I.. 2012. Two new species of nematodes (Cephalobida: Chambersiellidae) from moss from North and South America. Nematropica 42:108-114.
Goodey, T. 1952. Soil and Freshwater Nematodes: A Monograph. Methuen, London. 390pp.
Massey, C.L. 1963. Santafea new genus (Rhabditoidea, Chambersiellidae) and a change in the systematic position of Macrolaimus Maupas, 1900. Proc. Helminthol. Soc. Wash. 30:26-28.
Rahm, G. F. 1928. Alguns nematodes parasitas e semiparasitas das plantas culturaes do Brasil. Arch. Inst. Biol. Andina Lima, 1 : 239-252.
Rahm, G.F. 1929. Nematodes parasitas e semi-parasitas de diversas plantas culturaes do Brasil. Arch. Inst. Biol. Andina Lima, 1,2: 67-135.
Sanwal, K.C. 1960. Taxonomic position of Macrolaimus papillatus (Rahm, 1928) Goodey, 1951, status of Diastolaimus Rahm, 1928, and emended diagnoses of Chambersiellidae and Chambersiella Cobb, 1920.(Nematoda). Canadian J. Zoology 38:751-753.
Sanwal, K. C. 1971. Geraldius n. gen., Macrolaiminae n. subfam., with a revision of the subfamilies and genera of Chambersiellidae (Nematoda). Canadian J. Zoology 49:965-967.
Truskova, G.M. & Eroshenko, A.S. 1977. Nematodo-fauna vegetativnykh organov travjanistykhi i drevesnykh rastenij elnikov primorja. Trudy Biologio-Pochvennogo Instituta 47, 35-49.
Von Daday, J. 1905. Untersuchungen �ber die S�sswasser-Mikrofauna Paraguays. Zoologica. Stuttgart 18 (44):1-374.