160 



J.B. RICHARDSON, R.M. RODRIGUEZ AND S.J.E. SUTHERLAND 



Remarks. The Cantabrian material has close-packed wide based 

 coni to spinose elements, some biform. The elements are not mixed 

 with minute cone as in typical forms of the species. 



Occurrence. Rare. Upper San Pedro Formation, Argovejo, Lower 

 MN (NA) Sub-Biozone. 



Cymbosporites sp. B 



PI. 10, fig. 3 



Description. Amb subtriangularto subcircular, usually preserved 

 in polar compression. Proximal surface laevigate, contact areas 

 covered by a thin diaphanous exine (hilum), near the periphery of the 

 contact areas are distinct arcuate folds, which form a constant 

 character, usually destroyed except near the margin. Outside the 

 contact areas the exine is much thicker, equatorially and distally, 

 1 .5-2 pm (measured equatorially ). Sculpture confined to the equato- 

 rial margin and distal hemisphere; consists of broad based coni 

 rounded in plan and evenly tapered in profile, c. 1 .5 \iva wide and > 1 

 \im high; sculptural elements spaced, but with insufficient distance 

 between them for elements of a similar size. Triradiate mark not seen 

 apart from curvatural invaginations at the radial apices. 



Dimensions. 26-31 |jm (based on 1 1 specimens). 



Comparisons. Similar to Cymbosporites cf. catillus Allen 1 965 in 

 Richardson & Lister 1969 except that the coni are broad-based and 

 larger. 



Remarks. Other specimens which may belong to the genus have 

 been found in the Argovejo and Geras sections, namely 

 1 Cymbosporites sp. A (PI. 10, fig. 2) and Cymbosporites sp. (PI. 10, 

 figs 4, 5). 



Occurrence. Upper San Pedro Formation, Argovejo, Geras, and 

 La Vid, EC Biozone and rare lower MN (NA) Sub-Biozone. 



TAXONOMY OF CHITINOZOA 



As the main purpose of this paper is to define a spore biozonation for 

 the Cantabrian region, only Ramochitina villosa (formerly 

 Gotlandochitina Laufeld 1974) is described briefly here. A more 

 detailed investigation of the chitinozoans from the Cantabrian Area 

 is to be presented in a forthcoming publication. All material is 

 deposited in the collections of the Natural History Museum, London. 



Order PROSOMATIFERA Eisenack 1972 



Family LAGENOCHITINIDAE Eisenack 1931. emend Paris 1981 



Subfamily ANGOCHITININAE Paris 1981 



Genus RAMOCHITINA Sommer & van Boekel 1964, emend. 



Paris effl/. 1999 



Type species. Ramochitina ramosi Sommer & van Boekel, 1 964: 

 426, pi. l,fig. 3. 



Ramochitina villosa (Laufeld 1974) 



PI. 13, fig. 7 



1974 Gotlandochitina villosa Laufeld: 95, figs 7a, b. 



1994 Go?/flHi^/r)c/»7/HflV';7/oM Laufeld; Sutherland: 65, pi. 17, figs 



7-14. 



Holotype. LO 4587 T, figured Laufeld, 1974: fig 56a. 



Diagnosis. (After Laufeld, 1974: 95). Body spheroidal, neck 

 cylindrical to subcylindrical; broadly rounded flexure. Ornament of 

 spines which may exhibit simple branching; spines on apertural 



portion of vesicle curved in aboral direction and in opposite direction 

 on the apertural portion of vesicle; spines on neck decrease in size 

 towards oral pole. 



Discussion. In the generic revision of Paris, Winchester-Seeto, & 

 Grahn (2000) Gotlandochitina Laufeld 1974 is considered a junior 

 synonym of Ramochitina Sommer & van Boekel 1964. G. villosa is 

 here transfened to Ramochitina. 



Acknowledgements. We are indebted to the Natural Environment Re- 

 search Council for research grant GR3/09624: to Katie Bagshaw and Denise 

 Darwin for technical assistance and for preparing material and picking spores 

 for light and SEM microscopy; Peter York is thanked for the light 

 photomicrographs, Chris Jones and Alex Ball for help with SEM studies; and 

 Derek Adams. Natural History Museum Photographic Unit, who composed 

 the plates electronically. 



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