Runcaria, a Middle Devonian seed plant precursor

• Published in: Science (American Association for the Advancement of Science) Vol. 306; no. 5697; pp. 856 - 858
• Main Authors: Gerrienne, P, Mayer-Berthaud, B, Fairon-Demaret, M, Streel, M, Steemans, P
• Format: Journal Article Web Resource
• Language: English
• Published: Washington, DC American Association for the Advancement of Science 29.10.2004; The American Association for the Advancement of Science; Amer Assoc Advancement Science
• Subjects: Belgium; Biological Evolution; Earth sciences; Earth sciences & physical geography; Earth, ocean, space; Evidence; Evolution; Exact sciences and technology; Fossils; Geological time; Givetian age; History; Individualized Instruction; Integument; Megaspores; Microspores; Paleobotany; Paleontology; Phanerogams; Physical, chemical, mathematical & earth Sciences; Physiological aspects; Physique, chimie, mathématiques & sciences de la terre; Plant architecture; Plant evolution; Plant morphology; Plant Physiological Phenomena; Plant reproduction; Plant Structures - anatomy & histology; plant taxonomy; Plants; Plants - anatomy & histology; Plants - classification; Pollen; Pollination; Sciences de la terre & géographie physique; Seed plants; Seeds; Specimens; Taxa; Time; Belgium; Western Europe; Paleozoic; Middle Devonian; Givetian; Devonian; paleontologic reconstruction; morphology; Europe; seeds; Plantae; sporangia; stratigraphy
• ISSN: 0036-8075; 1095-9203; 1095-9203
• DOI: 10.1126/science.1102491

The emergence of the seed habit in the Middle Paleozoic was a decisive evolutionary breakthrough. Today, seed plants are the most successful plant lineage, with more than 250,000 living species. We have identified a middle Givetian (385 million years ago) seed precursor from Belgium predating the earliest seeds by about 20 million years. Runcaria is a small, radially symmetrical, integumented megasporangium surrounded by a cupule. The megasporangium bears an unopened distal extension protruding above the multilobed integument. This extension is assumed to be involved in anemophilous pollination. Runcaria sheds new light on the sequence of character acquisition leading to the seed.