Frenelopsis (Coniferales: Cheirolepidiaceae) And Related Male Organ Genera From The Lower Cretaceous Of Spain

Abstract

ABSTRACT. Vegetative plant remains and microsporangiate cones, related to the fossil genera Frenelopsis and Classostrobus respectively, were studied in three localities from the Lower Cretaceous of the Pyrenees and Iberian Ranges (Spain). Sterile remains belong to three different species: F. rubiesensis Barale, F. ugnaensis sp. nov. and F. turolensis sp. nov. The male cones Classostrobus ugnaensis sp. nov. and C. turolensis sp. nov. are associated with the two latter species respectively, and C. turolensis is found in connection with F. turolensis. Internodes of F. ugnaensis display small hemispherical papillae and long conical hairs covering the entire cuticle surface, while F. turolensis has a strip of hairs near the leaf margin, in addition to more massive outer stomatal papillae and higher stomatal density. The tiny cones of C. ugnaensis bear microsporophyll cuticles capped with vermiculate¯attened papillae and a fringe of marginal hairs, while C. turolensis has a central area of microsporophylls covered by long conical hairs. Sedimentological and taphonomic analyses show that the assemblages studied belong to a wide spectrum of habitats. These indicate that Spanish Lower Cretaceous frenelopsids were xeromorphic plants, able to adapt to helophytic and riparian habitats, and grew in brackish coastal marshes and¯uvio-lacustrine freshwater environments.

Fossil calibrations for the cockroach phylogeny (Insecta, Dictyoptera, Blattodea), comments on the use of wings for their identification, and a redescription of the oldest Bla

“…Martin-Closas and Lopez-Moron (1995) dated these formations to the Barremian Stage (125.45 Ma) as they lay within limestone bearing the charophyte Atopochara trivolvis triquetra Grambast, 1968(Martinez-Delclos, 1990). The layer beneath bears benthic foraminifera of Berriasian age (Gomez et al, 2002), and the layer above it is categorized by rich fauna of orbitolinids, dated to the Late Barremian or Early Aptian age (Gomez et al, 2002), consistent with the Barremian estimate. Though some studies (e.g., Brenner et al, 1974) have given older age estimates for the charophyte bearing limestone strata yielding C. montsecana, but we accept the more recent, more conservative age.…”

Cheirolepidiacean foliage and pollen from Cretaceous high-latitudes of southeastern Australia

“…However, the sunken stomata protected by two ranks of papillae strongly favours cheirolepidiacean affinities (Watson, 1988). Similar deeply sunken stomata protected by a double ring of papillae occur on some Northern Hemisphere Cheirolepidiaceae leaves (Gomez et al, 2002b), such as: Frenelopsis, e.g., Frenelopsis alata (Feistmantel) Knobloch, 1971(Alvin, 1977Kvaček, 2000) from the Cretaceous of Europe and U.S.A.; Frenelopsis harrisii Doludenko and Reymanowna, 1978 from the Cretaceous of Tajikistan (Watson, 1988); and Frenelopsis hoheneggeri (Ettingshausen) Schenk emend. Reymanówna and Watson, 1976, from the Cretaceous of Poland and the Czech Republic (Gomez et al, 2002b).…”

“…Two main groups of Cheirolepidiaceae are generally recognized based on differences in their shoot morphology: the so-called frenelopsids and nonfrenelopsids. Frenelopsids have predominantly a whorled phyllotaxis and the representative genera (e.g., Frenelopsis and Pseudofrenelopsis) are found mainly in Laurasia (Alvin et al, 1981;Alvin, 1982;Francis, 1983;Watson, 1988;Clement-Westerhof and van Konijnenburg-van Cittert, 1991;Zhou, 1995;Guignard et al, 1998;Watson and Alvin, 1999;Daviero et al, 2001;Gomez et al, 2002b;Axsmith, 2006;Yang et al, 2006;Mendes et al, 2010;Bartiromo et al, 2012), but a few are also known from Gondwana (Watson, 1983;Kunzmann et al, 2006;Sucerquia et al, 2008). The non-frenelopsids have leaves borne in a spiral arrangement and include representatives of genera such as Brachyphyllum (Watson, 1988;Du et al, 2013) and Watsoniocladus (Srinivasan, 1995) from Laurasia, and Tomaxellia and Tarphyderma (Archangelsky, 1963(Archangelsky, , 1966(Archangelsky, , 1968Taylor, 1986, 1991;Villar de Seoane, 1998;Kunzmann et al, 2006) from Gondwana.…”

“…Early studies from Laurasia highlighted their diminutive leaves, strong stomatal protection and common association with sediments of semi-arid or coastal environments, or to areas subject to repeated volcanic ash fall, in inferring that these xeromorphic plants were adapted to dry, saline or disturbed habitats (Vakhrameev, 1970;Watson, 1977;Upchurch and Doyle, 1981;Alvin, 1982;Francis, 1983Francis, , 1984Archangelsky and Taylor, 1986;Watson, 1988). More recent studies indicate that the plants occupied a wider variety of environments (Gomez et al, 2002b;Mendes et al, 2010) but their full environmental tolerances remain poorly constrained. The distinctive pollen assigned to Classopollis is more characteristic of low-latitude megathermal-mesothermal palynoprovinces than higher latitude (temperate) settings during the Cretaceous (Alvin, 1982;Dettmann, 1992).…”

Gymnosperms from the Early Cretaceous Crato Formation (Brazil). II. Cheirolepidiaceae

“…5D) possibly indicates succulence (e.g., Axsmith & Jacobs 2005). However, the common interpretation of frenelopsids as arid coastal forest-inhabiting xerophytes (Vakhrameev 1970) was modified by Gomez et al (2002). They asserted that the frenelopsids were adapted to a wider ecological range and thus habitats of different species might have varied substantially.…”