Archaeamphora longicervia

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The division of living beings into systematics is a continuous subject of research. Different systematic classifications exist side by side and one after the other. The taxon treated here has become obsolete due to new research or is not part of the group systematics presented in the German-language Wikipedia.

Archaeamphora was the name of several 1998 and 2001 they found in China fossils as an extinct species of the family under the Hongqi Li 2005 Pitcher plants described (Sarraceniaceae). With an age of around 125 million years, the species would have been the oldest known carnivorous plant species and one of the oldest known species of bedspreads . Later investigations on the basis of new finds showed that this was not a new species, but malformations caused by insects ( plant gall ) on Liaoningocladus boii and thus corrected Li 's spectacular results.

description

As a kind after Li

Li described the fossils as an herbaceous plant that was around 50 millimeters high. Along the longitudinally grooved stem, at least 21 millimeters long and 1.2 millimeters thick, there were three- to five-veined phyllodes as well as stalked and 30 to 40 millimeters long, slightly upwardly curved, tubular leaves that were strongly bulged towards the middle and arranged in a spiral slightly tapered towards the top.

The outward-facing (abaxial) part of the leaf merged into an operculum at the peristome , the opening of the tube, a lid-shaped, rounded leaf extension at the upper end of the tube, which was cut round towards the middle and tapered to a point at its outermost point. A clearly thickened midrib also ran vertically abaxially, and a wing parallel to the midrib ran adaxially (i.e. pointing towards the center of the plant). The wings, bulge and operculum were veined like a network. In the lower area of ​​the tubes, up to one millimeter high deposits could be found in the fossils, as they also occur in recent carnivore species with pitfall traps as a result of the carnivory .

In the tubes as well as along the external nerve , Li was able to identify different types of glands that were structured as in recent carnivore species. On the one hand, he was able to detect sessile glands, similar to those that excrete waxy substances inside pitfall traps so that the inside of the trap did not provide any support for prey. He also found glandular hairs that resembled those that secreted digestive enzymes in recent carnivores.

In the immediate vicinity of two fossil A. longicervia , oval, 0.9 millimeter wide and 1.25 millimeter long seeds were found. Its surface was wart-shaped, with a wing on the edges. No fossils of flowers, fruits or roots were found.

As an insect gall according to Wong et al.

Wong describes a branch with spirally arranged leaves and a single leaf fragment. The leaves are lanceolate, 50–80 millimeters long and 2–6 mm wide, with almost parallel veins, about four to eleven-veined on the widest part of each leaf. On different parts of four leaves arise from the leaf veins pear-shaped swellings that reach a length of 4 to 10 millimeters and a width of 4 to 5 millimeters. This is completed by an elliptical to circular zone, which often represents a depression of around 0.8 millimeters. Li Wong interpreted these structures as the traps of a carnivorous plant Archaeamphora longicervia .

However, since the overall appearance of the leaves is of the conifer Liaoningocladus boii G. Sun et al. (helically arranged, narrowly lanceolate, 20 to 70 millimeters long and 2 to 5 millimeters wide, four to eleven-nerved with almost parallel leaf veins) Wong explains the swellings as plant gall, which can be seen as abnormal swellings on the leaves next to healthy leaves.

Distribution and Finds

All finds of the genus come from the Yixian Formation , the oldest part of the Jehol group in today's northeastern China. Li was presented with nine specimens of Archaeamphora longicervia , including the holotype CBO0220 and the paratype CBO0754.

Habitat

The plant lived under subtropical, temperate, moist conditions in a landscape characterized by lakes, but otherwise arid to semi-arid . The soils were sandy and contained volcanic ash due to the numerous active volcanoes in the area, the lakes were rich in minerals due to the high volcanic activity. The mean temperature at that time was around 15 ° C above today's level, and the CO 2 content in the atmosphere was also significantly higher.

The flora of the region was characterized by conifers , mosses , bear mats , horsetail , ferns , Bennettitales , Czekanowskiales , Ginkgoales and Gnetales . Other cloud coverings like Archaefructus were rare and small.

Systematics

Detection of oleanane (a substance that is only found in bed covers ) led Li to classify Archaeamphora longicervia as bed covers . The great morphological similarity of the tubes, the glandular apparatus and the seeds with the recent pitcher plants (especially with the red pitcher plant and the marsh jugs ) allowed him to be integrated into pitcher plants .

Further finds of similar, but morphologically different plants in the formation suggested for Li that the genus had already been split into different species at this point in time and thus had a longer evolutionary history. Due to their advanced development and with reference to further research results, Hongqi Li therefore considered it possible that the first covering plants did not appear in the Mesophytic but as early as 280 million years ago in the Paleophytic .

When interpreted as bile, these conclusions became irrelevant, but they brought the findings back into line with numerous other findings on the origins and ages of the Sarraceniaceae family and the Bedecktsamer.

Individual evidence

  1. ↑ a b c d e f g h Hongqi Li: Early Cretaceous sarraceniacean-like pitcher plants from China. In: Acta Bot. Gallica. 152 (2), 2005, pp. 227-234. ( Online version ( Memento from February 22, 2016 in the Internet Archive ); PDF; 2.84 MB; with fossil photos)
  2. ^ A b c William Oki Wong, David Leonard Dilcher, Conrad C. Labandeira, Ge Sun, Andreas Fleischmann: Early Cretaceous Archaeamphora is not a carnivorous angiosperm. In: Frontiers in Plant Science. Vol. 6, 2015, p. 326. ( online ( memento from August 13, 2015 in the web archive archive.today ))
  3. ^ Paul M. Barrett, Jason M. Hilton: The Jehol Biota (Lower Cretaceous, China): new discoveries and future prospects. In: Integrative Zoology. 1 (1), 2006, pp. 15-17. doi : 10.1111 / j.1749-4877.2006.00006.x
  4. ↑ Jing-Jing Tan, Dong Ren: Ovatucupes: A New Cupedid Genus (Coleoptera: Archostemata: Cupedidae) From The Jehol Biota (Late Jurassic) Of Western Liaoning, China. In: Entomological News. Vol. 117, Number 2, March-April 2006. ( Online version ( Memento from February 21, 2014 in the Internet Archive ); PDF; 242 kB)
  5. ^ Zhou Zhonghe: Evolutionary radiation of the Jehol Biota: chronological and ecological perspectives. In: Geological Journal. Vol. 41, 2006, p. 384.
  6. ^ MJ Sanderson, JL Thorne, N. Wikstrom, K. Bremer: Molecular evidence on plant divergence times. In: Am. J. Bot. 91, 2004, pp. 656-1665.
This article was added to the list of articles worth reading on March 11, 2007 in this version .