136 



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



MATERIALS AND METHODS 



Type and figured palynomorphs for this paper are housed in the 

 Palynology Laboratory, Department of Palaeontology, The Natural 

 History Museum, London. Figured specimens have either FM num- 

 bers (spores) or FC numbers (chitinozoa). Spores are located on 

 slides, while for SEM images the number refers to the relevant stub. 

 Letters and numbers (eg. LV 92/17 (DE) 3, 179 0914) refer to 

 section, year of collection, sample, (maceration), slide number and 

 lastly the specimen location co-ordinates taken on a Zeiss 

 Photomicroscope III (n. 2562) housed in the Palynology Section of 

 the Palaeontology Department. E.F. numbers are the England Finder 

 co-ordinates (e.g. J33/1) of the specimen location. BM numbers 

 refer to SEM photographic negatives held in the archives of The 

 Natural History Museum, London. SEM stubs and strew, or picked 

 specimens, were coated with gold palladium. Spores were studied on 

 Hitachi S800 and Phillips XL 30 field emission SEM's and, in 

 addition, some chitinozoans were studied on a Hitachi S2500. Mount- 

 ing methods for the chitinozoa are as described by Sutherland 

 (1994); spores are strewn, mainly on mica, secured to the stub with 

 araldite S2. Numbering of chitinozoan specimens follows the same 

 pattern as described for the spores, eg. sample number ARGl 1 A, 

 slide number 508/12, stub box reference SB4/45, England Finder 

 reference (Q27/4). 



The light photomicrographs were taken on a Zeiss photomicro- 

 scope using Normarski differential interference with x 60 or x 100 

 objectives and a plate camera and were all taken by Mr. Peter York of 

 the Natural History Museum. 



Sporomorphs and chitinozoa were extracted from rock samples 

 using standard paiynological methods. Because of the high matura- 

 tion of much of the material schultze's solution was usually used but 

 light microscope and SEM studies revealed that even very fine 

 sculptural detail was preserved, comparable with that seen in Eng- 

 lish Lower Devonian material with low maturation (Richardson, 

 1996b). Residues were strewn on slides and dried and covered with 

 either elvacite or epoxy resin. 



A duplicate set of samples is preserved in the Mining and Engi- 

 neering Department, University of Leon. 



TAXONOMY OF SELECTED SPORE TAXA 



Anteturma SPORITES H. Potonie 1893 

 Turma TRILETES (Reinsch 1881) Potonie & Kremp 1954 



Subturma AZONOTRILETES Luber 1935 

 Genus RETUSOTRILETES (Naumova) Richardson 1965 



Type species. Retusotriletes pychovii Naumova 1953 (lectotype 

 species of Richardson 1965). 



Remarks. The great variability of smooth taxa is illustrated by 

 Rodriguez (1983). Two genera in particular show a great deal of 

 variation. The genus Archaicusporites has a thin proximal face with 

 an apical triangular thickening, but otherwise is similar in structure 

 to the genus Archaeozonotriletes. There is also a complex of retusoid 

 spores and. in particular, the spores placed in the species R. coronadus 

 Rodriguez 1983 include laevigate forms, and forms with apiculate 

 sculpture which herein are placed in two genera. 



Retusotriletes bipellis Rodriguez, 1978 



PI. 2, fig. 1 



Rodriguez. 1978c: pi. 3, fig. 2; San Pedro Formation, Torrestio, 

 Province of Leon, Cantabrian Mountains, northwest Spain. 



Dimensions. Rodriguez 1978c. 40-70 lam; present study 30^8 

 |jm (based on 10 specimens). 



Remarks. These miospores have a thin proximal exine and may 

 grade into species of Archaicusporites. 



Occurrence. Found in all sections, occurring from the EC 

 Biozone to the NA Sub-Biozone (MN Biozone), Upper Piidolf and 

 Lower Lochkovian. 



Retusotriletes coronadus (Rodriguez, 1983) emend 



1978 Retusotriletes communis Naumova; Rodriguez: pi. 4, fig. 



12. 

 1983 Retusotriletes coronadus Rodriguez (pars): pi. 9, figs 1, 10? 



(nonpl. 8, figs 1, 8). 



Diagnosis. Trilete retusoid azonate spores with relatively thin 

 contact areas and a thickened proximal triangle surrounding a thin 

 apical area. 



Comparisons. Archaicusporites asturicus and A. torrestionensis 

 (Rodriguez, 1983) (PI. 10, fig. 8) are similar but have thicker equa- 

 torial and distal walls. 



Remarks. Spores originally placed in this taxon show consider- 

 able morphological diversity. The figure of the holotype (Rodriguez, 

 1983: pi. 9. fig. 1 ) is different from the other specimens illustrating 

 the original description, and appears to have a dark triangle on the 

 proximal surface similar to Archaicusporites asturicus (Rodriguez. 

 1983: pi. 7, fig. 3). The epithet R. coronadus is retained pending re- 

 examination of the holotype. Other spores belong to two separate 

 morphologies, the first (Form 1) with a highly distinctive double 

 curvaturate structure (Rodriguez, 1983: pi. 8. fig. 1). the second 



PLATE 2 



Fig. 1 Retusotriletes bipellis Rodriguez 1978c. FM 1496. la, shows Y-mark and folded proximal membrane; lb, double ridged curvaturae and laevigate 



distal exine. Ger92/I5a, (469) 3. 213 0959. 

 Figs 2, 3 Retusotriletes? saturnus sp. nov. 2a, FM 1498. proximal view shows distinct triangular area at the spore apex; 2b, shows concentric curvatural 



thickenings, LV92/17 (D3) 3. 152 0928; 3, FM 1497. proximal view showing trilete folds, LV92/17 (D3) 3. 179 0914. 

 Fig. 4 Apiculiretusispora arcidecus sp. nov. FM 1499. 4a, 4b, proximal view, showing grana and microconi forming the curvaturae perfectae; 4c, detail of 



curvaturae at radial apex. X 1.500. LV92/13 (D3) 1.066 0952. 

 Figs 5-7 Breconisporitesl spp. 5, FM 1500. proximal view with an equatorial crassitude, arcuate zones of thickening, thinnest in the radial areas 



surrounding a thin apical triangular area with radial folds, and a distal polar thickening, Arg92/ 14 (468) 11, 138 0893; 6, FM 1501, similar specimen with 



distinctly granulate equator. LV92/13 (495) 2. 195 0960; 7a, b, FM 1502; 7a proximal view; 7b distal focus showing annulus and polar thickening, slide 



Arg92/14(468) 11,083 1072. 

 Fig. 8 Emphanisporites splendens Richardson & loannides 1979. 8a, 8b FM 1503, showing radial ribs, distinct annulus and large inter-radial thickenings, 



Ger92/2B(477)2, 165 0961. 

 Fig. 9 Emphanisporites sp. FM 1 504. Ger92/2B (477) 2, 1 66 ( 



All figs X 1000. unless stated otherwise. 



