Millerocaulis (Erasmus) ex Tidwell (Osmundales, Filices) from the Carrrizal Formation (Upper Triassic) from Marayes, San Juan province, Argentina

Abstract

Millerocaulis (Erasmus) ex Tidwell (Osmundales, Filices) from the Carrrizal Formation (Upper Triassic) from Marayes, San Juan province, Argentina. Based on newly found specimens, «Marayea lutzi» Herbst 1994, of the Upper Triassic Carrizal Formation, from Marayes (San Juan province , Argentina) is analyzed. Anatomical characters, specially those from the central cylinder, now defines the species as an ectophloicdictyoxylic siphonostele (sensu Miller) and shows that it must be changed to Millerocaulis. Thus, Marayea defined as a siphonostelic genus becomes invalid and an emended diagnosis for the type species is given. Also, from the same locality and age other, rather big specimens, are described. They are not well preserved but the available characters allow to incorporate them as Millerocaulis sp. These two species and others formerly described of this genus, M. herbsti

The fossil Osmundales (Royal Ferns)—a phylogenetic network analysis, revised taxonomy, and evolutionary classification of anatomically preserved trunks and rhizomes

“…References: Archangelsky & de la Sota (1962, 1963), Bower (1926), Cantrill (1997), Cheng (2011), Cheng & Li (2007), Cheng, Wang & Li (2007), Edwards (1933), Gupta (1970), Gwynne-Vaughan (1911), Herbst (1977, 1994, 1995, 2001, 2006, 2008), Kidston & Gwynne-Vaughan (1907, 1910), Marshall (1926), Matsumoto et al (2006), Miller (1971), Prynada (1974), Rothwell, Taylor & Taylor (2002), Seward (1907), Sharma (1973), Sinnott (1914), Tian, Wang & Jiang (2008), Tian et al (2013, 2016), Tidwell (1986, 1992, 1994, 2002), Tidwell & Ash (1994), Tidwell & Clifford (1995), Tidwell & Rushforth (1970), Tidwell, Munzing & Banks (1991), Vera (2007, 2008, 2010), Vishnu-Mittre (1955) and Wang (1983).…”

“…Whereas classification of end members in this spectrum is rather straightforward, the range of variation represented—especially in the diverse array of Mesozoic osmundoid rhizomes—makes a categorical classification difficult (Vera, 2008). This is further complicated by the fact that the development of complete perforations in the xylem cylinder depends on the ontogenetic stage of the individual specimen and on the level at which it is sectioned (Vera, 2008; see also Seward & Ford, 1903; Wardlaw, 1946, 1947; Hewitson, 1962; Gould, 1970; Cantrill, 1997; Herbst, 2001, 2006; Fig. 4).…”

Alienopteris livingstonensis gen. et sp. nov., enigmatic petrified tree fern stem (Cyatheales) from the Aptian Cerro Negro Formation, Antarctica

“…Developmental stages of the fossil ferns are difficult to study, and sometimes two fossil species may represent two ontogenetic stages of only one species (see Herbst (2001Herbst ( , 2006 for examples in the Osmundaceae). In this case, the meristelar morphology of Alienopteris may be interpreted as a result of the fossilization of basal or apical sections of cyatheoid stems, where it differs from the one found along the trunk.…”

Fossil woods from Argentina (1884–2021)

“…Records with the mere mention of fossil wood names, if they do not have at least some description or illustration of anatomical features, are not included (e.g., Darwin 1839;Frenguelli 1946;Archangelsky & Brett 1960;Artabe & Zamuner 1991;Ganuza et al 1998;Zucol et al 2005). The database does not include palms (e.g., Ancíbor 1995) and tree ferns (e.g., Herbst 2006), plants that lack typical secondary xylem. However, it includes manoxylic gymnosperms like cycads (e.g., Martínez et al 2012).…”