The Triassic is a geologic period and system which spans 50.5 million years from the end of the Permian Period 251.902 million years ago (Mya), to the beginning of the Jurassic Period 201.4 Mya. The Triassic is the first and shortest period of the Mesozoic Era and the seventh period of the Phanerozoic Eon. Both the start and end of the period are marked by major extinction events. The Triassic Period is subdivided into three epochs: Early Triassic, Middle Triassic and Late Triassic.
Gnetophyta is a division of plants, grouped within the gymnosperms, that consists of some 70 species across the three relict genera: Gnetum, Welwitschia, and Ephedra. The earliest unambiguous records of the group date to the Jurassic, and they achieved their highest diversity during the Early Cretaceous. The primary difference between gnetophytes and other gymnosperms is the presence of vessel elements, a system of small tubes (xylem) that transport water within the plant, similar to those found in flowering plants. Because of this, gnetophytes were once thought to be the closest gymnosperm relatives to flowering plants, but more recent molecular studies have brought this hypothesis into question, with many recent phylogenies finding them to be nested within the conifers.
Bennettitales is an extinct order of seed plants that first appeared in the Permian period and became extinct in most areas toward the end of the Cretaceous. Bennettitales were amongst the most common seed plants of the Mesozoic, and had morphologies including shrub and cycad-like forms. The foliage of bennettitaleans is superficially nearly indistinguishable from that of cycads, but they are distinguished from cycads by their more complex flower-like reproductive organs, at least some of which were likely pollinated by insects.
Palissya is an extinct form genus of female (ovule-bearing) conifer cones, known from the Late Triassic (Rhaetian) to the Early Cretaceous (Aptian). The cone of Palissya is noted for its unusual catkin-like construction: Slender bracts are rigidly attached in a helical pattern around a tall woody core. The adaxial (upper) surface of each bract bears two parallel rows of ovules which are encased in cup-like structures formed by scales. The seeds are thin-walled and were likely only viable for a short period of time, meaning that they were probably adapted to wind dispersal.
Pleuromeia is an extinct genus of lycophytes related to modern quillworts (Isoetes). Pleuromeia dominated vegetation during the Early Triassic all over Eurasia and elsewhere, in the aftermath of the Permian–Triassic extinction event. During this period it often occurred in monospecific assemblages. Its sedimentary context in monospecific assemblages on immature paleosols, is evidence that it was an opportunistic pioneer plant that grew on mineral soils with little competition. It spread to high latitudes with greenhouse climatic conditions.
Cunninghamites is an extinct genus of conifers in the family Cupressaceae of the European Late Cretaceous flora.
Omma is a genus of beetles in the family Ommatidae. Omma is an example of a living fossil. The oldest species known, O. liassicum, lived during the final stage of the Triassic (Rhaetian), over 200 million years ago, though the placement of this species in Omma has been questioned. Numerous other fossil species are known from the Jurassic and Cretaceous of Europe and Asia. The only living species is Omma stanleyi, which is endemic to Australia. Three other extant species endemic to Australia that were formerly part of this genus were moved to the separate genus Beutelius in 2020.Omma stanleyi is strongly associated with wood, being found under Eucalyptus bark and exhibiting thanatosis when disturbed. Its larval stage and many other life details are unknown due to its rarity. Males are typically 14–20 mm in length, while females are 14.4-27.5 mm. Omma stanleyi occurs throughout eastern Australia from Victoria to Central Queensland.
Nilssonia is a genus of fossil foliage traditionally assigned to the Cycadophyta either in Cycadales or their own order Nilssoniales, though the relationships of this genus with the Cycadales have been put into question on chemical grounds.
Zamites is a genus of sterile foliage known from the Mesozoic of North America, Europe, India and Antarctica through the Eocene of North America. It was erected as a form taxon for leaves that superficially resembled the extant cycad Zamia, however it is now believed to belong to a similar but phylogenetically different group, the cyacadeoids (Bennettitales). The fronds are linear or lanceolate in shape, and pinnately compound, with pinnae with parallel veins and smooth margins, and symmetrical and constricted at the base where they are attached obliquely to the upper surface of the rachis. It has been interpreted as a Bennettitalean plant in the family Williamsoniaceae. It is associated with the ovulate cone Williamsonia and male cone Weltrichia.
Lepidopteris is a form genus for leaves of Peltaspermaceae, an extinct family of seed plants, which lived from around 260 to 190 million years ago, from the Late Permian to Early Jurassic. Fossils of the genus have been found across both hemispheres. Nine species are currently recognized.Lepidopteris was a common and widespread seed fern, which survived the Permian-Triassic extinction event but was largely wiped out by the Triassic-Jurassic extinction event. Lepidopteris callipteroides is especially common between the first two episodes of the Permian-Triassic extinction event, and L. ottonis forms a comparable acme zone immediately before the Triassic-Jurassic extinction event. Lepidopteris would persist into the Early Jurassic in Patagonia, represented by the species Lepidopteris scassoi.
The Exter Formation is the only formation of the Upper Keuper or Rhätsandstein, and is a geologic formation in Germany. It preserves fossils dating back to the Rhaetian of the Triassic period.
This article records new taxa of plants that are scheduled to be described during the year 2017, as well as other significant discoveries and events related to paleobotany that are scheduled to occur in the year 2017.
Baiera is a genus of prehistoric gymnosperms in the order Ginkgoales. It is one of the oldest fossil foliage types of Ginkgoales, and is related to the genera Ginkgo and Ginkgoites. Fossils of Baiera are found worldwide, and have been known from the Permian to the Cretaceous.
Mesoblattinidae is an extinct, problematic family of cockroaches known from the Mesozoic. It was formerly considered a wastebasket taxon for Mesozoic cockroaches, but the family has subsequently been better defined, with many taxa transferred to Caloblattinidae. It is considered to have close affinities with Blattidae and Ectobiidae, as well as possibly Blaberidae. The family first appeared by the Early Jurassic. They are considered to represent amongst the oldest groups of modern cockroaches, and like them are thought to have laid oothecae. Due to the poor ability of forewing venation to correctly classify cockroaches to extensive homoplasy, the value of this family as a taxonomic unit has been strongly questioned, with some authors considering the family a nomen dubium.
Pterophyllum is an extinct form genus of leaves known from the Carnian to the Maastrichtian, belonging to the Bennettitales. It contains more than 50 species, and is mainly found in Eurasia and North America.
Czekanowskiales, also known as Leptostrobales, are an extinct group of seed plants. Members of the family are distinguished by persistent leaves borne on deciduous short shoots, subtended by scale-like leaves. The leaves are highly dissected. They likely grew as trees and shrubs. The main ovulate structure of Czekanowskiales, Leptostrobus, consists of bivalved seed-bearing round capsule-like structures arranged along a long axis. The fossil record of Czekanowskiales is largely confined to the Northern Hemisphere, and they inhabited warm-temperate and temperate climates under humid conditions. The oldest possible records of the group are ovulate cones from the Late Permian of Italy, but the group is primarily known from the Late Triassic onwards, and were abundant during the Jurassic and Early Cretaceous. Only a handful of species are known from the Late Cretaceous, confined to the northern Russian Far East, corresponding to the decline of other seed plant groups during the explosive radiation of flowering plants. The affinites of Czekanowskiales to other seed plants are obscure. A close relationship to the Ginkgoales has been proposed, based on similar preserved molecular signatures of fossil cuticles, with some authors placing Ginkgoales and Czekanowskiales into the broader grouping Ginkgophyta.
Nilssoniopteris is an extinct form genus of leaves belonging to the Bennettitales. Leaves are slender and often entire-margined (smooth-edged), though some species have dissected leaves with numerous small segments extending down to the rachis of the leaf. Nilssoniopteris-like leaves are distinguished by their syndetocheilic stomata, indicating bennettitalean affinities. Similar "taeniopterid" leaves are placed in the genus Nilssonia if their stomata are instead haplocheilic, or Taeniopteris if the cuticle is not preserved. Leaves of Nilssoniopteris vittata from the Middle Jurassic of England are associated with bisexual Williamsoniella reproductive structures.
Orthophlebiidae is an extinct family of scorpionflies known from the Triassic to Cretaceous, belonging to the superfamily Panorpoidea. The family is poorly defined and is probably paraphyletic, representing many primitive members of Panorpoidea with most species only known from isolated wings, and has such been considered a wastebasket taxon.
Wielandiella is an extinct genus of bennettitalean shrub known from the Late Triassic (Rhaetian) of Europe and Greenland, and the Middle Jurassic of China.
Komlopteris is an extinct genus of "seed fern" with possible corystosperm affinities. Fossils have been found across both hemispheres, dating from the latest Triassic to the early Eocene (Ypresian), making it the youngest "seed fern" in the fossil record.
