150 



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



Emended diagnosis. Equatorial crassitate miospores with 

 rounded or convexly triangular amb, a proximal kyrtome of thick- 

 ened arcuate ridges extending to the radial apices where it is 

 flat-topped and joins with the trilete lips; distal surface with, or 

 without, a distal annulus; distal exine laevigate. verrucate, irregu- 

 larly murornate, or reticulate. 



Comparison. The rounded amb and distinct kyrtome distinguish 

 this genus. There is no kyrtome on the type species of Amicosporites 

 (A. splendidi(s) but two other species, A. infraornatus Rodriguez 

 1978b and A. subornator Cramer and Diez 1975 have this structure 

 and are herein transferred to Coroiiaspora. The kyrtome in 

 Ahrensisporites Potonie & Kremp, 1954 and Concavisporites Pflug 

 in Thomson and Pflug, 1953 are distinct because the radial parts are 

 prominent and inter-radially the amb is straight to concave. The 

 kyrtome tapers evenly towards the equator in Kyrtomisporis Madler 

 1964 (see also Achilles, 1981 ) whereas in Cownaspora the kyrtome 

 is a radially broad and flattened (truncated) thickening where the 

 inter-radial branches of the kyrtome meet, and may invaginate to 

 become confluent with the lips. In cross-section the Silurian kyrtomes 

 have a semicircular-shape. 



Remarks. Rodriguez validated the genus in 1 979 when she desig- 

 nated Coronaspora mariae as type species. 



Coronaspora cromatica (Rodriguez) emend 



PI. 6, fig. 6; PI. 8, figs 1^ 



1978b Coronaspora cromatica Rodriguez: 218, pi. 1, fig. 4. 

 1979 Coronaspora cromatica (Rodriguez) Jansonius & Hills: 



card number 3543. 

 1983 Coronaspora cromatica Rodriguez: pi. 3, fig. 4. 



HOLOTYPE. Rodriguez, 1978b: 218, pi. 1, fig. 4. 



Emended diagnosis. A Coronaspora with distinct labra, a proxi- 

 mal kyrtome with inter-radial thickenings, distal annulus, and variable 

 muri and verrucae in the distal polar region. 



Description. Amb subcircular to subtriangular with convex sides. 

 Spores preserved in polar compression suggesting an original of 

 more or less lenticular shape. Exine proximally with a distinct 

 complete kyrtome with inter-radial thickenings, radial 'bars', con- 

 necting these to a narrow (c. 3 |jm), +/- smooth to irregularly 

 thickened, equatorial crassitude. Kyrtome distinct, formed by raised 

 ridges (+/- semi-circular in profile) paralleling the lips in the inter- 

 radial areas, flattened at radial extremities where it may show 

 distinct invaginations; lips variably developed, may be broad and 

 verrucate often taper sharply to the apices, or may be laevigate and 

 sinuous; in forms with verrucate lips sutures distinct. Distally an 

 annulus has smooth to irregular margins c. 9 |im wide, outer border 



of annulus reaches to 2/3 of the spore radius. Distally polar area 

 sculptured by broad muri 3-7 |im wide, 9-18 |am long, muri highly 

 variable in shape and orientation, forming linear or sinuous bars 

 which may be smooth-sided, or show a series of constrictions giving 

 a beaded appearance, due to the mixture of verrucae and short muri, 

 or coalescent verrucae. 



Dimensions. 28^7 pm (58 specimens measured); Rodriguez, 

 1978b, 20-30 |jm; width of the cingulum c. 2 pm. 



Comparisons. Coronaspora mariae also has a distal annulus and 

 is closely similar but has large rounded verrucae over the distal pole. 



Remarks. Rare specimens with sinuous laevigate lips, like the 

 type material (Rodriguez, 1978b), occur in the Upper part of the San 

 Pedro Formation. So far the forms with smooth lips have only been 

 found in the upper H to EC Zones. Specimens with verrucate lips 

 occur in the upper RS Zone and may prove to be a useful marker for 

 the lower boundary of the Pfidoli. 



Occurrence. Formswithverrucatelips(Pl. 6,fig. 6,P1.8,figs 1- 

 4) occur in the Lower San Pedro Formation; lower upper RS Biozone 

 Geras, Argovejo, lower H La Vid and La Peral sections; spores with 

 laevigate lips, C. cf. cromatica. Upper San Pedro Formation, upper 

 H & EC Biozone La Peral, EC & lower MN Biozones La Vid. 



Coronaspora reticulata sp. nov.Pl. 6, fig. 7; PI. 8, figs 5, 6 



1975 Knoxisporites? riondae Cramer & Diez (pars): 341, pi. 1, 



fig. 17 only. 

 1978c Knoxisporites? riondae Cramer & Diez; Rodriguez : 42, 43, 



pi. 2, figs 18, 19. 

 1983 Knoxisporites! riondae Cramer & Diez: Rodriguez {pars): 



42, 43, pi. 4, figs 2, 3. 



Holotype. FM 1491 (Pi. 8, fig. 6), diameter 36 |im; sample La Vid 

 7B, slide D3/3, co-ord. 043 0965; E.F. no. E27/1; lower San Pedro 

 Formation, La Vid section, Province of Leon, Cantabrian Mountains, 

 northwest Spain. 



Diagnosis. A Coronaspora with broad distal muri forming a 

 reticulum; kyrtome thickened especially in the inter-radial areas; 

 kyrtome surrounds a clover-leaf shaped area of thin exine; laesurae 

 labrate, labra narrow, smooth and sinuous. 



Description. Amb circular to subcircular. Spores usually pre- 

 served in polar compression, suggesting an original, more-or-less 

 lenticular cross-section. Equatorial crassitude smooth +l~ 2 \xm. 

 Kyrtome smooth, invaginated and increasing in width towards the 

 spore apex in the inter-radial areas, 2-4 pm, joined at the radial 

 apices where they may be slightly invaginated at the junction with 



PLATE 9 



Fig. 1 Chelinospora cantabrica sp. nov. FM 1493, (holotype); la, distal focus showing a reticulum of broad muri, several with characteristic narrow 



restrictions; lb, shows equatorial margin and muri in plan. Arg92/5a (473) 3, 144 1082. 

 Fig. 2 Chelinospora iavidensis sp. nov. FM 1494 (holotype). showing narrow muri forming an irregular reticulum with subequatorial muri normal to the 



equator, Arg92/12 (510) 3, 093 1019. 

 Figs 3, 5 Chelinospora hemiesferica (Cramer & Diez) comb. nov. 3, FM 1 53 1 ; 3a, proximal view showing thick crassitude and narrow concentric fold at 



the equatorial edge of the hilum; 3b, distal surface showing close-packed narrow geniculate muri, Ger92/9 (450) 1, 147 1050; 5, FM 1532 tetrad, showing 



parallel subequatorial muri normal to the equator and geniculate muri over the distal patina. Arg92/ 14 (468) 1 1.080 1069. 

 Fig. 4 Chelinospora cf hemiesferica (Cramer & Diez) comb. nov. 4, FM 1533; 4a, distal view, muri geniculate, but broader and more spaced than in the 



species; 4b. proximal focus showing margins of the hilum. Arg92/1 la (441 ) 4, 074 0915. 

 Fig. 6 Chelinospora media sp. nov. FM 1495, holotype, Arg92/12 (510) 3, 093 1019. 

 Fig. 7 Cymbosporites cf dittonensis Richardson & Lister 1969. FM 1534, Arg92/13 (455) 1, 049 1014. 



All figs X 1000. 



