Facies (2017) 63:27 DOI 10.1007/s10347-017-0508-x ORIGINAL PAPER About Trinocladus Raineri, 1922: when some Permocalculus (Gymnocodiacean algae) reveal to be Triploporellacean algae (Revision of the Jesse Harlan Johnson Collection. Part 5) Bruno Granier1,2 · Ioan I. Bucur3 · Dimas Dias‑Brito4 Received: 25 March 2017 / Accepted: 10 August 2017 / Published online: 5 September 2017 © Springer-Verlag GmbH Germany 2017 Abstract The Upper Cretaceous-Paleogene genus Trino- tripolitanus, Raineri described a tiny species which was later cladus that is based on T. tripolitanus Raineri, 1922, origi- revised by Pia, i.e., Dissocladella ondulata. D. bonardii, a nally described from Libyan material, is morphologically name recently introduced by Radoičić et al. and which is well constrained. Its species are commonly distinguished on based on Raineri’s original material, is considered here as the basis of their biometrics. However, the narrow Gauss- an objective junior synonym of D. ondulata. ian distribution reported for some measurements may result from post-mortem dynamic sorting as suggested by a review Keywords Cretaceous · Dasycladales · Trinocladus · of the surrounding microfacies. An examination of Brazilian Dissocladella · Biometric limitation material of the type-species suggests a slightly club-shaped thallus morphology. Two “false Permocalculus” species originally described by Johnson and the type-material of Introduction which has been reexamined are formally reascribed to the genus Trinocladus. T. budaensis, the smallest one, has When studying some fossil “calcareous” algae, the impact slightly club-shaped thallus, too. T. elliotti is poorly min- of various factors, among which a weak mineralization in eralized and insufciently documented. In addition to T. the form of metastable aragonite, a centripetal micritization, the mechanical sorting of the bioclasts derived from them and their mechanical abrasion, may signifcantly afect the * Bruno Granier three-dimensional reconstructions of their thalli. In the case bgranier@univ‑brest.fr; [email protected] studied, we must bear in mind that the outer cortical layer of Ioan I. Bucur some Dasycladales, e.g., Trinocladus Raineri, 1922, vaguely [email protected] ressembles that of some Halimedaceae or Gymnocodiaceae Dimas Dias‑Brito (both Bryopsidales), e.g., Permocalculus Elliott, 1955. In [email protected] addition, weak mineralizations on the main axis and on 1 Dépt. STU, Fac. Sci. Tech, UBO, CS 93837, 29238 Brest, the proximal part of the laterals for the Dasycladales or on France the medullar flaments for the Bryopsidales may result in a 2 Department of Ecology and Evolutionary Biology, The poor preservation of the inner parts of the original aragonitic University of Kansas, 1200 Sunnyside Avenue, Lawrence, coatings and can explain the common misinterpretation of KS 66045, USA the original algal architectures. 3 Department of Geology and Center for Integrated Geological For instance, as for the “Inventory of the fossil Dasy- Studies, Babeş-Bolyai University, M. Kogălniceanu str., 1, cladalean algae” (Delofre and Granier 1992; Granier and 400084 Cluj‑Napoca, Romania Delofre 1993), the genus Trinocladus Raineri, 1922, was 4 Center for Geosciences Applied to Petroleum supposedly known from the Late Jurassic to the Oligocene (UNESPetro) and Departamento de Geologia Aplicada, (with a hiatus in the earliest Cretaceous). With the exclu- UNESP-Universidade Estadual Paulista, Av. 24 A, no. 1515, Bela Vista, Caixa Postal 178, Rio Claro, SP CEP 13506‑900, sion of some Jurassic specimens that were erroneouly Brazil ascribed to T. perplexus Elliott 1955, and later redescribed Vol.:(0123456789)1 3 27 Page 2 of 12 Facies (2017) 63:27 as Thyrsoporella pseudoperplexa Granier et Braik 2002, the clastic wackestones. Part of this material was illustrated stratigraphic range of the genus is currently restricted to the by Granier (2015). “mid-“ Cretaceous—Oligocene interval. Although some forms were erroneously interpreted as representatives of the genus Trinocladus, the opposite is also true. The present The genus Trinocladus and its type‑species paper, which is the ffth contribution to the “Revision of the Jesse Harlan Johnson Collection” (Granier et al. 2013, 2017; The type-species is T. tripolitanus Raineri, 1922. It was Granier and Dias-Brito 2016; Basso and Granier 2017), also originally documented by two fgures (Raineri 1922, Pl. III, re-examines the case of two Trinocladus species that John- fgs. 15–16). The frst fgure (Raineri 1922, Pl. III, fg. 15), son (Johnson and Kaska 1965; Johnson 1968) erroneously that Pia selected as the “type” (lectotype), is a transverse ascribed to the genus Permocalculus. section that displays the typical arrangement with three orders of pores, left behind in lieu of the laterals. Accord- ing to Pia (1936) who frst revised Raineri’s material, the Material primary pores are “approximatively club-shaped”; “the secondary pores repeat on a smaller scale the shape of the The material studied comes from four collections primary pores, narrow at their bases, expanding outward”; hosted in three countries in turn, “the tertiary pores are short and slender”, possibly widening outward to form an external cortex. The second fgure (Raineri 1922, Pl. III, fg. 16) is a long oblique sec- 1. The J. Pfender Collection is hosted at Sorbonne Univer- tion, that provides a glimpse of what tangential and axial sity—Pierre et Marie Curie University, Paris (France). sections look like. However, in this fgure, only two orders of We re-examined three thin sections from Turonian strata pores are visible. This pattern is not typical of Trinocladus, in Provence, SE France: but it is characteristic of Dissocladella (Pia in L.R. Rao et Pia, 1936). No. 90 “Barres Le Revest, Trinocladus tripolitanus, Boueinia”, No. 90 bis “W de Costebelle, Trinocladus ondulatus”, The Libyan Dissocladella controversy No. 90 ter “W Costebelle, Trinocladus”. This material was previously revised by Massieux (in Pfender and According to Pia (1936) Trinocladus is an intermediary Massieux 1966). genus between Dissocladella and Thyrsoporella. (see Bas- soullet et al. 1978). Besides Trinocladus tripolitanus, Raineri 2. The J.H. Johnson Collection is hosted at the Smithso- (1922, p. 75–76, Pl. III, fgs. 7–11) introduced a “Neomeris nian National Museum of Natural History, Washington, cretacea Stein. var. ondulata”. Pia (1936), who re-examined D.C. (U.S.A.). It comprises one thin section U.S.N.M. Raineri’s material, treated this variety as a genuine species, No. 42547 from the “mid-” Cretaceous (Albian- but he reascribed it to the genus Dissocladella. Incidentally Cenomanian) of Guatemala and a set of eleven thin sec- he slightly modifed the spelling of the specifc epithet from tions U.S.N.M. Nos. 42607-42617 from the Buda Fm ondulata to undulata. (Cenomanian) of Texas, U.S.A. Each set is associated According to the I.C.B.N. (2012, Art. 8 and 40), there to a species described by Johnson (1968; Johnson and was no need for the authors to select a “type (holotype, lec- Kaska 1965). totype, or neotype) of a name of a species” before 1 January 3. The P. Tibana Collection was temporarily hosted with 1958. The fve original fgures were considered as syntypes the UNESPetro’s collections at the UNESP-Universi- and there was a need to select one of them as the lectotype. dade Estadual Paulista, Rio Claro, S.P. (Brazil). Tibana’s Although one of the fve original Raineri’s specimens (1922, material is from the Bonfm Fm (Cenomanian) of the Pl. III, fg. 7) was the most poorly preserved, Radoicic et al. Barreirinhas basin; thin sections Nos. 281-282 have a (2005, Pl. I, fg. 1) unfortunately selected it as the lecto- well-sorted grain-supported fabric whereas thin section type. Regarding this specimen, Pia (1936) even stated that No. 68-53 has a mud-supported fabric. The remaining it “is possibly some other fossil, not an alga”. In addition, set of ffteen thin sections found at the UNESPetro (Nos. Radoičić et al. (2005) reascribed it with doubt to the genus 87B, 88A&B, 89B, 91B, 92A&B, 93A&B, 94A&B, Trinocladus Raineri 1922, and, as they said, it “is expected 95A&B, and 96A&B) are from the Jandaira Fm (Turo- to remain ill-defned”. Regarding the four remaining speci- nian—lower Campanian) of the Potiguar basin; their mens (Raineri 1922, Pl. III, fgs. 8–11), this group of authors fabric is mud-supported and their texture is that of bio- (Radoičić et al. 2005) assigned them to a species that they 1 3 Facies (2017) 63:27 Page 3 of 12 27 newly introduced, i.e., Dissocladella bonardii Radoičić et al. Bryopsidales (with both larger medullar flaments and cor- 2005. tical flaments). These forms are associated to other algae, Due to the above mentioned issues and to the untenable e.g., Boueinia sp. and Marinella lugeoni Pfender, 1939, in confict with Pia’s (1936) protologue (i.e., the species was well-sorted grain-supported fabrics. described as a Dissocladella, with two orders of laterals, not as a Trinocladus, with three orders of laterals) and the strong opinion of Radoičić et al. (2005) about the specimen New biometric observations on Brazilian they selected as lectotype, a new lectotype designation is Trinocladus tripolitanus specimens then requested. This new lectotype designation should super- sede Radoičić et al.’ designation. Accordingly we select here We could not examine Raineri’s material, which was previ- another Raineri’s specimen (1922, Pl. III, fg. 8) as the new ously revised by Pia (1936), but the species is quite com- lectotype of the species Dissocladella ondulata (Raineri, mon in the Upper Cretaceous strata of Brazil. Our speci- 1922), Pia 1936. Consequently, D. bonardii Radoičić et al. mens come from two localities: one in the Barreirinhas basin 2005, should be treated as an objective junior synonym of (Bonfm Fm, Cenomanian: Figs. 2a–c, 3b, c) and one in the the Raineri’s taxon.
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