# Cryptospore > Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Cryptospore > Markdown URL: https://mediated.wiki/source/Cryptospore.md > Source: https://en.wikipedia.org/wiki/Cryptospore > Source revision: 1325440001 > License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) {{Short description|Fossilised primitive plant spore}} '''Cryptospores''' are microscopic [fossilized](/source/fossil) [spore](/source/spore)s produced by [embryophytes](/source/Embryophyte) (land plants). They first appear in the [fossil](/source/fossil) record during the middle of the [Cambrian](/source/Cambrian) period{{cite journal |last1=Strother |first1=Paul K. |title=A Fossil Record of Spores before Sporophytes |journal=Diversity |date=22 July 2024 |volume=16 |issue=7 |page=428 |doi=10.3390/d16070428 |bibcode=2024Diver..16..428S |doi-access=free }}, as the oldest fossil evidence for the colonization of land by plants. A similar (though broader) category is '''miospores''', a term generally used for spores smaller than 200 [μm](/source/Micrometre). Both cryptospores and miospores are types of [palynomorphs](/source/Palynology).{{Cite journal |last=Steemans |first=P |date=2000 |title=Miospore evolution from the Ordovician to the Silurian |url=https://linkinghub.elsevier.com/retrieve/pii/S0034666700000592 |journal=Review of Palaeobotany and Palynology |language=en |volume=113 |issue=1–3 |pages=189–196 |doi=10.1016/S0034-6667(00)00059-2|pmid=11164219 |bibcode=2000RPaPa.113..189S |url-access=subscription }} Cryptospores, which occur as permanent tetrads, dyads, or hilate monads, sometimes with additional wall envelopes, dominated fossil assemblages for approximately 60 million years, first appearing around 470 million years ago during the Ordovician Period. They underwent rapid diversification during what Jane Gray (1993) called the Eoembryophytic epoch,{{Cite journal |last=Gray |first=Jane |date=1993-09-01 |title=Major Paleozoic land plant evolutionary bio-events |url=https://linkinghub.elsevier.com/retrieve/pii/0031018293901275 |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |series=Event Markers in Earth History |volume=104 |issue=1 |pages=153–169 |doi=10.1016/0031-0182(93)90127-5 |bibcode=1993PPP...104..153G |issn=0031-0182|url-access=subscription }} but experienced an abrupt decline in diversity and abundance around 410 Ma during the latest [Lochkovian](/source/Lochkovian) (Early Devonian), with only a few forms persisting into the Emsian period. In contrast, trilete monads began diversifying around 430 Ma in the latter Silurian Period and eventually became the dominant element in dispersed spore assemblages. While trilete monads are generally associated with vascular plants, cryptospores lack close modern analogues (except possibly in some liverworts), making the identification of their parent plants one of evolutionary botany's significant unresolved problems.{{Cite journal |last1=Edwards |first1=Dianne |last2=Morris |first2=Jennifer L. |last3=Axe |first3=Lindsey |last4=Duckett |first4=Jeffrey G. |last5=Pressel |first5=Silvia |last6=Kenrick |first6=Paul |date=2022 |title=Piecing together the eophytes – a new group of ancient plants containing cryptospores |journal=New Phytologist |language=en |volume=233 |issue=3 |pages=1440–1455 |doi=10.1111/nph.17703 |pmid=34806774 |bibcode=2022NewPh.233.1440E |issn=1469-8137|doi-access=free }}Wellman CH, Steemans P, Vecoli M. 2013. Chapter 29 Palaeophytogeography of Ordovician–Silurian land plants. ''Geological Society, London, Memoirs'' 38: 461–476. ==Evidence that cryptospores derive from land plants== ===Occurrence=== Cryptospores are generally found in non-marine [rock](/source/Rock_(geology))s and decrease in abundance with distance offshore. This suggests that any cryptospores found in the [marine](/source/Marine_(ocean)) environment were transported there by the wind from the land, rather than originating from the marine environment. ===Wall ultrastructure=== The walls of cryptospores consist of many lamellae (thin sheets). [Liverwort](/source/Marchantiophyta)s, thought to be the most primitive [land plants](/source/land_plants), also have this spore wall [morphology](/source/Comparative_anatomy). ===Chemical composition === (Some) cryptospores are composed of sporopollenin and have the same chemical makeup as co-occurring trilete spores.{{cite journal|last=Steemans|first=P.|author2=Lepot, K. |author3=Marshall, C.P. |author4= Le Hérissé, A. and Javaux, E.J. |title=FTIR characterisation of the chemical composition of Silurian miospores (cryptospores and trilete spores) from Gotland, Sweden|journal=Review of Palaeobotany and Palynology|date=2010|volume=162|issue=4|pages=577–590|doi=10.1016/j.revpalbo.2010.07.006|bibcode=2010RPaPa.162..577S |url=https://hal-insu.archives-ouvertes.fr/insu-00558990/file/Organic_Geochem_Steemans.pdf}} ==Other information== Recently, fossils of plant [sporangia](/source/Sporangium) have been found in [Oman](/source/Oman) with cryptospores showing concentric lamellae in their walls, similar to [liverworts](/source/liverworts). The earliest known cryptospores are from Middle [Cambrian](/source/Cambrian) {{cite journal |last1=Strother |first1=Paul K. |title=A Fossil Record of Spores before Sporophytes |journal=Diversity |date=22 July 2024 |volume=16 |issue=7 |page=428 |doi=10.3390/d16070428 |bibcode=2024Diver..16..428S |doi-access=free }}. Spores from the Lindegård [Mudstone](/source/Mudstone) (late [Katian](/source/Katian)–early [Hirnantian](/source/Hirnantian)) represent the earliest record of early [land plant](/source/land_plant) [spores](/source/spores) from [Sweden](/source/Sweden) and possibly also from [Baltica](/source/Baltica) and implies that [land plants](/source/land_plants) had migrated to the [palaeocontinent](/source/palaeocontinent) [Baltica](/source/Baltica) by at least the Late [Ordovician](/source/Ordovician).{{cite journal|last=Badawy|first=A.S.|author2=Mehlqvist, K. |author3=Vajda, V. |author4= Ahlberg, P. and Calner, M. |title=Late Ordovician (Katian) spores in Sweden: oldest land plant remains from Baltica|journal=GFF|date=2014|volume=136|issue=1|pages=16–21|doi=10.1080/11035897.2014.899266|bibcode=2014GFF...136...16B |s2cid=22198834 |url=http://urn.kb.se/resolve?urn=urn:nbn:se:nrm:diva-1417}} This discovery reinforces the earlier suggestion that the migration of land plants from northern [Gondwana](/source/Gondwana) to [Baltica](/source/Baltica) in the Late [Ordovician](/source/Ordovician) was facilitated by the northward migration of [Avalonia](/source/Avalonia),{{cite journal|last=Steemans|first=P.|author2=Wellman, C.H. and Gerrienne, P. |title=Paleogeographic and paleoclimatic considerations based on Ordovician to Lochkovian vegetation|journal=Geological Society, London, Special Publications|date=2010|volume=339|pages=49–58|doi=10.1144/SP339.5|url=http://sp.lyellcollection.org/content/339/1/49.abstract|issue=1|bibcode=2010GSLSP.339...49S |s2cid=140195843 |url-access=subscription}} which is evidenced by the co-occurrence of reworked, Early–Middle [Ordovician](/source/Ordovician) [acritarchs](/source/acritarchs), possibly suggesting an Avalonian provenance in a [foreland basin](/source/foreland_basin) system. ==See also== *[Paleobotany](/source/Paleobotany) *[Palynology](/source/Palynology) ==References== {{reflist}} ==Further reading== * {{cite journal |last1=Edwards |first1=D. |last2=Morris |first2=J. L. |last3=Richardson |first3=J. B. |last4=Kenrick |first4=P. |year=2014 |title=Cryptospores and cryptophytes reveal hidden diversity in early land floras |journal=New Phytologist |volume=202 |number=1 |pages=50–78 |doi=10.1111/nph.12645|pmid=24410730 |bibcode=2014NewPh.202...50E |url=https://orca.cardiff.ac.uk/57757/1/EdwardsD.EARTH3.pdf }} Category:Fossil record of plants Category:Microfossils Category:Ordovician plants Category:Paleobotany Category:Paleozoic life Category:Palynology Category:Silurian life --- Adapted from the Wikipedia article [Cryptospore](https://en.wikipedia.org/wiki/Cryptospore) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Cryptospore?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.