Droserapites is a genus of extinct plants of somewhat uncertain droseracean affinity. It is a form taxon known only from fossilized pollen.
Fossil record
Pollen of D. clavatus has been found in the Miocene Peliao Sandstone of Taiwan.[1]
Affinities
Droserapites has generally been regarded as having probable affinity with Droseraceae, primarily because its pollen occurs in tetrads (groups of four) and resembles that of extant Drosera.[1][2] Pollen tetrads are a distinctive feature of Droseraceae and are unusual among flowering plants, supporting the interpretation of Droserapites as a fossil form taxon with probable droseracean relationships.[3] In his formal description of the genus, Tseng-Chieng Huang suggested that Droserapites may be related to Droseridites and Quadrisperites.[1]
Morphology
Droserapites pollen grains are united in tetrads (groups of four). Individual grains are inaperturate. The exine is mixed with dense, superposed clavate and baculate processes, whereas the sexine is reticulate.[1]
The tetrads of D. clavatus are tetrahedral and 34–40 μm in diameter. Individual grains are subspheroidal and measure 18–25 μm in width. They have a roughly circular amb that is abruptly acute at the distal pole. The exine is 0.5–1 μm thick, with 2–3 μm long clavae or bacula.[1]
References
- ^ a b c d e f Huang, Tseng-Chieng 1978. “Miocene palynomorphs of Taiwan. II. Tetrad grains” (PDF). Botanical Bulletin of Academia Sinica 19: 77–81.
- ^ Song, Z.-C., W.-M. Wang & F. Huang 2004. Fossil pollen records of extant angiosperms in China. The Botanical Review 70(4): 425–458. doi:10.1663/0006-8101(2004)070[0425:FPROEA]2.0.CO;2
- ^ Fleischmann, Andreas; Schlauer, Jan; Smith, Stephen A.; Givnish, Thomas J. (2018). “Evolution of carnivory in angiosperms”. In Ellison, Aaron M.; Adamec, Lubomír (eds.). Carnivorous Plants: Physiology, ecology, and evolution. Oxford University Press. doi:10.1093/oso/9780198779841.003.0003.