The extinct conifer family Cheirolepidiaceae is notable for its distinctive Classopollis pollen and its dominance over vast areas in the Jurassic and Early Cretaceous, particularly regions that show evidence of hot and dry climate (e.g., Southern Laurasia in the Late Jurassic, Northern Gondwana in the Early Cretaceous). Most Jurassic members have short, scalelike leaves of the Brachyphyllum type; these are joined in the Early Cretaceous by frenelopsids, including Frenelopsis (usually three leaves per node) and Pseudofrenelopsis (usually one leaf per node), which are even more xeromorphic than Brachyphyllum in having jointed shoots with highly reduced leaves, photosynthetic internodes, unusually thick cuticle, and sunken stomata with a ring of papillate subsidiary cells. There were early indications that the two genera occupied different parts of a salinity gradient. Pseudofrenelopsis varians is dominant in the lagoonal Glen Rose Formation of Texas (lower Albian), while Pseudofrenelopsis parceramosa occurs in brackish facies in the Potomac Group of Virginia (Aptian). By contrast, at the Fredericksburg locality in Virginia (lower Albian), Frenelopsis ramosissima is associated with diverse ferns, gymnosperms, and angiosperms in sediments that show no evidence of marine influence. However, F. ramosissima also occurs in the Glen Rose, and younger Frenelopsis species are dominant in lagoonal and saltmarsh facies, such as Frenelopsis alata in the Cenomanian of Bohemia and France. Here we report a much older frenelopsid species, Pseudofrenelopsis sp. nov., from the lower Hauterivian of the Santa Susana Formation at the Vale Cortiço clay pit complex in the Lusitanian Basin of western Portugal. It has leaves on mature shoots with a sheathing base, attenuate apex, and marginal trichomes, terminal branches with Brachyphyllum-type foliage, and only moderately thick cuticle. Although the Santa Susana environment has been interpreted as estuarine to upper deltaic, the palynoflora shows no evidence of marine influence. The mesofossil flora is dominated by the previously described species Frenelopsis teixeirae and Pseudofrenelopsis sp. nov., but Classopollis makes up only ca. 20% of the palynoflora, and spores are diverse and abundant (45%). These observations suggest that both frenelopsid species may have grown in non-saline sites in the upper part of a delta system, where most of the palynoflora was derived from upstream forests of diverse gymnosperms and ferns. Pseudofrenelopsis parceramosa dominated such environments in the Barremian of England, where its xeromorphic features have been interpreted as adaptations to occasional periods of severe drought and forest fires in a generally wet climate. These observations indicate that both Frenelopsis and Pseudofrenelopsis showed a trend from freshwater and brackish environments before the Albian to drier and more saline environments in the Albian and Cenomanian, possibly due to competitive replacement by angiosperms in inland vegetation.