54 



PALEOZOIC FOSSIL SPORES 



Genus Lycospora S. W. and B., gen. nov. 

 Plate 3, figures 19-19b 



Symmetry. — Spores radial ; trilete. 



Form. — Flattened lenticular as seen in 

 lateral profile, equator marked with a 

 short thick tapering ridge ; nearly circu- 

 lar or very broadly triangular in the 

 transverse plane. Compression is gener- 

 ally parallel to the transverse plane with 

 few or no folds, due to preferential ori- 

 entation of the spores. 



Size. — Mean diameter in various spe- 

 cies ranging from about 18 to 45 microns. 



Ornamentation. — Spores nearly 

 smooth ; minutely granulose or rugose. 

 Sometimes the minute rugae tend to be 

 more prominent radially. 



Haptotypic features. — Trilete rays ex- 

 tended nearly to margin, suture lines dis- 

 tinct, usually without noteworthy differ- 

 entiation of lips. In species with most 

 strongly developed emphytic ornament, 

 the haptotypic features also are more 

 prominent. The equatorial ridge corre- 

 sponds to the arcuate ridge in its origin 

 and rarely becomes so extended and mem- 

 branous across its width as to resemble 

 a typical flange development. Usually it 

 is narrow and tapers evenly and rapidly 

 away from the spore body; in some spe- 

 cies it may be almost nonexistant. 



Spore coat. — Relatively thin, sometimes 

 less than 1 micron thick on proximal and 

 distal surfaces and quite translucent. 

 Thicker at the equator where there is no 

 easily defined line of demarcation between 

 the equatorial ridge and the body wall. 



Affinity. — Spores of this type have fre- 

 quently been encountered in the tips of 

 Lepidostrobus cones and there is little 

 doubt that most of these forms found iso- 

 lated represent microspores of the arbor- 

 eous lepidodendrids. Andrews and Pan- 

 nell (1942) have described similar forms 

 which persist in tetrad groupings as mi- 

 crospores of a species of Lepidocarpon. 

 The microspores of sigillarians (as shown 

 by Mazocarpon) are significantly larger 

 and probably are not included in Lyco- 

 spora (cf. Schopf, 1941). 



Spores assigned to type D^^ by Raistrick 

 belong without question to Lycospora, 

 also probably his B^ and D2 Type in part 

 (Raistrick and Simpson, 1933, Raistrick, 

 1937, 1938). Knox (1938) has recog- 



nized the relationship of these types to 

 Lepidostrobus and compared D^ and D2 

 with Lepidostrobus jacksoni and L. old- 

 hamius respectively. Type D^^ which she 

 illustrates may also belong to Lycospora. 



There is, of course, great inherent un- 

 certainty in identifying any species of 

 Lepidostrobus from isolated microspores 

 alone. Microfossils of this kind obtain- 

 able from coal probably are derived from 

 many more species than are likely to be 

 recognized from entire fructifications be- 

 cause cones are essentially more fragile 

 and require more favorable conditions for 

 their good preservation than spores do. 

 The spores probably constitute a more 

 compete record of the various closely re- 

 lated forms, whether they can be distin- 

 guished easily from one another or not. 



Reinsch (1884) has illustrated a num- 

 ber of forms, chiefly from central Russia 

 and from Zwickau, Saxony, which are 

 probably referable to Lycospora. His 

 numbered diagnoses 32, 81, 83, 87, 240 

 424 ( ?), 525 ( ?) and 550 may be cited. 



Remarks. — Four species previously de- 

 scribed are assigned to Lycospora all of 

 which represent new name combinations. 

 Lycospora micro papillata (Wilson and 

 Coe) is designated as the type species. 

 The genus is well represented in the Penn- 

 sylvanian; several additional species have 

 been recognized but are not yet described. 



1. Lycospora micropapillatus (Wilson and 

 Coe) S. W. and B., comb. nov. 



Cirratriradites micropapillatus Wilson 

 and Coe, 1940, Am. Midland Naturalist, 

 vol. 23, no. 1, p. 184, fig. 6. 



2. Lycospora minutus (Wilson and Coe) 

 S. W. and B., comb. nov. 



Cirratriradites minutus Wilson and 

 Coe, 1940, idem, p. 183, figs. 11 and 12. 



3. Lycospora pellucidus (Wicher) S. W. 

 and B., comb. nov. 



Sporitcs pellucidus Wicher, 1934, List. 

 Palaobot. Arb., vol. 4, no. 3, p. 186, pi 

 8, fig. 29. ' i^ . 1^ ■ 



4. Lycospora pusillus (Ibrahim) S. W. and 

 B., comb. nov. 



Sporonites pusillus Ibrahim, 1932, Neues 

 Jahrb., Beilage-Band 67, Abt. B., p. 448, 

 pi. 15, fig. 20. 



Zonales-sporites pusillus (Ibrahim) Ib- 

 rahim, 1933, Sporenformen des Aegirhor- 

 izonts, p. 32, pi. 2, fig. 20. 



Granulati-sporites pusillus (Ibrahim) 

 Loose, 1934, Inst. Palaobot. Arb., vol. 4, no. 

 3, p. 146, pi. 7, fig. 3. 



