garly Cretaceous macrofloras 
Sphenopteris sp. A 
Figures 5G,H 
1 961 'Neorhachopteris minuta' White; p. 303; plate 5, 
figure 4. [1961a]. 
c f. 1961 Ruffordia mortoni Walkom; White; p. 304; 
plate 5, figures 6, 7. [1961a], 
1993 Sphenopteris sp. B; McLoughlin and Guppy; 
figure 8. 
jvlaterial 
WAM P.64.14, WAM P.89.167, WAM P.89.170, 
VVAM P.89.173, WAM P.89.175 WAM P.89.186. 
distribution 
Broome Sandstone (Neocomian-Barremian), 
Canning Basin. 
description 
Frond elliptical, at least bipinnate, 50 mm wide, 
85 mm long. Rachis stout (2 mm wide) at base, 
tapering distally, straight or slightly sinuous, 
pinnae arranged alternately at 35°-50° to rachis, 
linear or arched distally, reaching 4 mm wide, 50 
mm long (Figure 5H). Rachilla with prominent 
central longitudinal ridge (on moulds). Pinnules 
inserted alternately by contracted or slightly 
decurrent base. Pinnules rhomboid to elliptical, 
reaching 2 mm wide, 4 mm long; apices rounded 
(Figure 5G). Venation dichotomous and gently 
divergent from base. 
Comments 
This species is distinguished from S. 
warragulensis by its small elliptical to rhomboid 
rather than lanceolate pinnules. Sphenopteris travisi 
Stirling and Sphenopteris sp. of Drinnan and 
Chambers (1986) and Ruffordia mortoni Walkom, 
1928 have more deeply dissected pinnules than 
Sphenopteris sp. A. The Jurassic Coniopteris sp. of 
Hill et al. (1966) has similar small rhomboid 
pinnules but Sphenopteris sp. A has much longer 
and proportionately narrower pinnae. 
Herbst's (1964) Argentinian Sphenopteris sp. has 
more rounded pinnules than the Western 
Australian form but the incomplete specimens of 
the former inhibit close comparisons. Kasat's (1970) 
Cladophlebis sp. cf. C. longipennis Seward from the 
Indian Early Cretaceous has a very similar gross 
frond structure to Sphenopteris sp. A but its 
pinnules possess distinct midribs. Other Indian and 
South African Sphenopteris species figured by Jain 
(1968), Sukh-Dev (1972a), Bose and Sah (1968), and 
Anderson and Anderson (1985) differ from the 
Western Australian specimen by their undulate, 
toothed, or deeply dissected pinnules. 
33 
Incertae sedis 
Genus Thinnfeldia Ettingshausen, 1852 
Type species 
Thinnfeldia rhomboidalis Ettingshausen, 1852; 
Early Jurassic; Steierdorf, Germany. 
Thinnfeldia cf. talbragarensis Walkom, 1921b 
Figures 6A,B 
1944 Thinnfeldia talbragarensis Walkom; Walkom; p. 
203; plate II, figure 8. 
1993 Thinnfeldia sp.; McLoughlin and Guppy; 
figure 10. 
Material 
UWA16690, UWA10472C. 
Distribution 
Leederville Formation and Bullsbrook Formation 
(Neocomian-Barremian), Perth Basin. 
Description 
Frond at least bipinnate, >90 mm long, 60 mm 
wide, elliptical. Rachis robust (<3 mm wide), 
longitudinally striate. Pinnae opposite, ovate to 
elliptical, L:W ratio 2:1 to 4:1, arising from rachis at 
60°-80°. Pinnae range from undulate-margined to 
deeply dissected into 4-7 pinnules (Figure 6A). 
Pinnule arrangement catadromous. Pinnules 
elliptical, wide-obovate, or rhomboid, reaching 5 
mm wide, 8 mm long; subopposite to alternate; 
apex rounded; base decurrent; venation 
odontopteroid (Figure 6B). 
Comments 
Walkom (1944) assigned material from the 
Leederville Formation to Thinnfeldia talbragarensis, 
a species erected for Jurassic fronds from New 
South Wales, but these specimens, together with 
additional specimens from the Bullsbrook 
Formation, differ from the eastern Australian form 
in having ovate-elliptical rather than lanceolate 
pinnules. Walkom's (1944: plate II, figure 8) 
illustration appears to be upside-down. Thinnfeldia 
media Tenison-Woods, 1883 figured by Jack and 
Etheridge (1892) from the Burrum Coal Measures, 
Queensland, and the Victorian Thinnfeldia sp. cf. T. 
indica Feistmantel, 1876 of Drinnan and Chambers 
(1986) which is probably synonymous with T. 
maccoyi Seward, 1904 differ from the Western 
Australian fronds by their less-dissected lanceolate 
pinnules. 
The Western Australian specimens bear some 
similarities to Ruflorinia pilifera Archangelsky, 
1964a from the Cretaceous of Argentina, however, 
the former specimens lack cuticular details 
necessary for close comparison to the South 
