Observations of clonal cultures of Euglyphidae (Rhizopoda, Protozoa) Colin G. Ogden Department of Zoology, British Museum (Natural History), Cromwell Road, London SW7 5BD Introduction The identification of small siliceous testate amoebae is often difficult due to three main factors, observations are made at the limits of the optical microscope, scarcity of specimens and inadequate descriptions. The introduction of scanning-electron microscopy for detailed surface examination has reduced the first of these obstacles, as this facility permits more accurate descriptions to be made of the shells of these animals. However, matching these more detailed descriptions with existing reports is often complicated as slight differences of shell structure have frequently prompted authors to propose new specific names, or new Varieties' or new 'forms'. The second factor can also be reduced by establishing clonal cultures in the laboratory; additionally such cultures enable one to study biology and variation in morphology. Previous reports (Hedley & Ogden, 1973, 1974; Hedley et al., 1974) dealt with the biology of four species, namely Euglypha acanthopora (Ehrenberg, 1841), E. rotunda Wailes, 191 1, E. strigosa (Ehrenberg, 1871) and Trinema lineare Penard, 1890. The present account describes the shell morphology and biology of four further species, based on clonal cultures, together with the redescription of a previous clone under a new specific name. Systematics The genera Euglypha and Assulina belong to the family Euglyphidae the classification adopted here is that proposed by Levine et al., 1980 and Loeblich and Tappan, 1964: Superclass RHIZOPODA Von Siebold, 1845 Class FILOSEA Leidy, 1879 Order GROMIIDA Claparede and Lachmann, 1859 Superfamily EUGLYPHACEA Loeblich and Tappan, 1 96 1 Family EUGLYPHIDAE Wallich, 1864 shell hyaline, symmetrical, elongate, composed of rounded siliceous plates, aperture rounded or elongate; one nucleus. Euglypha acanthophora In identifying specimens from a clonal culture as E. acanthophora Hedley et al. (1974) accepted the reported variation attributed to this species, although with some reservation because the extent of the variations was not substantiated by our obser-vations of other Euglypha species in culture. These differences mainly concerned the shape and position of the siliceous spines and the shape of the body plates, which are illustrated in Leidy's superb figures (Leidy, 1879) of E. alveolata a species accepted by both Cash et al., (1915) and Penard (in Cash et al.) as a synonym of E. acanthophora showing that the siliceous spines project either distinctly from the sides of the body or discretely from the aboral extremity, and that there are distinct tooth-like projections on the posterior edge of the body plates. Penard (1902) proposed two varieties to accommodate specimens with Bull. Br. Mus. not. Hist. (Zool.) 41(4): 137-151 Issued 26 November 1 98 1 137
BioStor
