Cycadodendron galtieri: Cycad wood from the Permian of Saxony, central-eastern Germany.

Cycads are a thought to have been among the earliest Gymnosperm Plants to have appeared, with molecular clock estimates suggesting that they diverged from other Gymnosperms in the Late Carboniferous or Early Permian. The group underwent a major evolutionary radiation in the Early Triassic, and fossils are abundant in Mesozoic and Cainozoic deposits. These fossils tend to closely resemble modern Cycads, despite these sharing a fairly recent common ancestor, suggesting a high degree of morphological conservatism within the group. Palaeozoic fossils are much less common, and can be more difficult to interpret. These comprise possible Cycad megasporophylls (leaves) from the Late Carboniferous and Early Permian, although it is difficult to be confident about the affinities of these.

In a paper published in the International Journal of Plant Sciences on 11 October 2023, Ludwig Luthardt of the Museum für Naturkunde at the Leibniz Institute for Evolution and Biodiversity Research, Ronny Rößler of the Museum für Naturkunde Chemnitz and the Department of Palaeontology at the Technische Universität Bergakademie Freiberg, and Dennis Stevenson of the New York Botanical Garden and the School of Integrative Plant Science at Cornell University, describe a new species of Cycad based upon a piece of stem wood from the Holocene gravel deposits of the Zwickauer Mulde river, which are known to produce silicified woods derived from the Permian Chemnitz Fossil Lagerstätte.

Geography and geology of the source area of the fossil Cycad stem, combining the catchment area of the Zwickauer Mulde River/Chemnitz River with the most important localities of mainly in situ found petrified wood and their stratigraphic affiliation. Abbreviations: NSVC, North SaxonyVolcanite Complex; ZVC, Zeisigwald Volcanic Complex. Luthardt et al. (2023).

The new species is named Cycadodendron galtieri, where 'Cycadodendron' means 'Cycad-tree' (the suffix '-dendron' is commonly used for fossil woods, on the basis that chunks of wood of any size must have come from a tree), and 'galtieri' honours Jean Galtier, a renowned palaeobotanist from Montpellier, France, for his significant contributions to the knowledge of the evolution and anatomy of Palaeozoic fossil Plants. It is described from a single piece of polished wood, K9883, roughly 69 mm by 56 mm, thought to have derived from a larger stem, as the outer parts, including the cortex and vestiges of leaf bases, are not preserved.

Overview of polished sections of Cycadodendron galtieri (K9883, holotype). (A) General view of the specimen in transverse section. K9883a. (B) Counterpart of the specimen, additionally cut in radial sections. K9883b, K9883c. (C), (D), Radial sections of the specimen; successivevascular cylinders are indicated by arrows and X1–X9 in (D). K9883b, K9883c. All specimens are at the same scale. Luthardt et al. (2023).

While foliage can be difficult to ascribe to a particular plant group, due to convergent evolution among plants living in similar environments, the wood of Cycads is highly distinctive, with vascular stands arranged in medullary bundles within a wide inner pith, surrounded by consecutive vascular segments each producing centripetal secondary xylem and centrifugal phloem. The presence of these features within Cycadodendron galtieri marks the specimen as an unequivocable Cycad, and therefore the oldest known fossil which can be confidently assigned to the group.

Anatomical sketches of Cycadodendron galtieri with the overall arrangement of stem tissues. (A) Transverse section showing the pith with medullary bundles and pith-peripheral bundles, successive vascular segments, and traversing medullary bundles. K9883a. (B) Radial section exhibiting vertical arrangement of stem tissues and indicating the number of successive vascular segments and phloem-parenchyma zones. K9883b. Luthardt et al. (2023).

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?Opsieobuthus tungeri: A Scorpion from the Permian Petrified Forest of Chemnitz in eastern Germany

Scorpions are a highly successful group of predatory Arachnids, with over 1750 described living species and a fossil record dating back to the Silurian. There are currently 131 described fossil Scorpion species, however these are not distributed evenly through the fossil record, with over sixty described species from the Carboniferous and less than ten from most other geological periods. To date Permian Scorpions are known only from some fragmentary remains from Isady in the Vologda Region of Russia and a trace fossil interpreted as a Scorpion track from Arizona.

In a paper published in the journal BMC Evolutionary Biology on 7 April 2016 Jason Dunlop of the Museum für Naturkunde at the Leibniz Institute for Research on Evolution and Biodiversity at the Humboldt University Berlin, David Legg of the Oxford University Museum of Natural History, Paul Selden of the Paleontological Institute at the University of Kansas and the Natural History Museum in London, Victor Fet of the Department of Biological Sciences at Marshall University, Joerg Schneider of the Geological Institute at TU Bergakademie Freiberg and the Kazan Federal University and Ronny Rößler also of the Geological Institute at TU Bergakademie Freiberg and of the Museum für Naturkunde in Chemnitz, describe a new species of Scorpion from the Early Permian Petrified Forest of Chemnitz in Saxony in eastern Germany.

The Chemnitz Petrified Forest is a preserved forest ecosystem buried by a pyroclastic flow, which contains one of the most complete known Permian ecosystems. As well as 53 upright tree stumps the system contains palaeosols (fossil soils) which an extensive root network and numerous chunks of detached wood. Animal fossils include Myriapods, Trigonotarbids, numerous Gastropods and some Vertebrate material

The new Scorpions are tentatively assigned to the Carboniferous genus Opsieobuthus and given the specific name tungeri in honour of the geologist Bernd Tunger for his work on the Chemnitz Petrified Forest. The species is described from two specimens, a tentatively identified as a male and a female, and is distinguished from other members of its genus on the basis of exceptionally large pectines (comb-shaped scent organs on the underside of a Scorpion), which protrude beyond the body.

Top: ?Opsieobuthus tungeri, female specimen (?), part and counterpart from the palaeosol beneath the Zeisigwald Tuff Horizon, Leukersdorf Formation (lower Permian, Sakmarian) of the Chemnitz Petrified Forest, Saxony, Germany. Bottom: Interpretative drawings of the specimens. Abbreviations: ac, aculeus; ca, carinae; ch ?, possible chelicera; cx, coxa; cxa, coxapophysis; le, lateral eyes; op, operculum; ot, ocular tubercle; pe, pedipalp; pec, pectines; ps, pedal spur; su, superimposed coxa and pectines; tc, tarsal claws; ts, tibial spur; ves, vesicle; wi, wing-like structure; ?, disarticulated cuticle fragment of uncertain affinity. Legs numbered from I–IV. Dunlop et al. (2016).

The tentative sexual differentiation of the specimens is based upon the pectines, which in modern Scorpions tend to be larger and have more teeth in males. The female specimen is 120 mm in length and preserved within what appears to be a burrow, along with some fragments of what may be a recently shed skin. The male specimen is 130 mm in length, although it appears to have been compressed in a way that shortened it when buried.

Top: ?Opsieobuthus tungeri, male specimen (?), part and counterpart from the palaeosol beneath the Zeisigwald Tuff Horizon, Leukersdorf Formation (lower Permian, Sakmarian) of the Chemnitz Petrified Forest, Saxony, Germany. Scale bar is 10 mm. Bottom: Interpretative drawings of the specimens. Abbreviations: ac, aculeus; ca, carinae; ch ?, possible chelicera; cx, coxa; cxa, coxapophysis; le, lateral eyes; op, operculum; ot, ocular tubercle; pe, pedipalp; pec, pectines; ps, pedal spur; su, superimposed coxa and pectines; tc, tarsal claws; ts, tibial spur; ves, vesicle; wi, wing-like structure; ?, disarticulated cuticle fragment of uncertain affinity. Legs numbered from I–IV. Dunlop et al. (2016).

Dunlop et al. note that the close proximity of the male to a recently ecdysed female (female that has recently shed its skin) is interesting, as many modern male Scorpions will find and guard female subadults close to maturity, mating with them once they moult and become sexually responsive, and suggest that the proximity of the two specimens may indicate similar behaviour in these Permian Scorpions.

See also...

Tityus apozonalli: A new species of Scorpion from Miocene Chiapas Amber.                    The ambers of Chiapas State, Mexico, were laid down in the Miocene (and possibly Oligocene) in shallow marine environments. The amber is thought to be derived from resin secreted from a Leguminous tree of the genus Hymenaea, which lived in mangrove...

A Scorpion from the Late Devonian of South Africa.                                                             Scorpions are thought to have been among the earliest Animals to colonize the land, with specimens...

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