Editing Spore

{{short description|Unit of reproduction adapted for dispersal and survival in unfavorable conditions}}
{{about|spores in eukaryotes|bacterial spores|endospore|other uses}}
{{Use dmy dates|date=July 2020}}
[[Image:Sporic meiosis.svg|thumb|300px|Spores produced in a sporic life cycle.]]
[[Image:Brachythecium rutabulum on Populus x canadensis.jpg|thumb|300px|Fresh snow partially covers rough-stalked feather-moss ''([[Bryopsida|Brachythecium rutabulum]])'', growing on a [[thinning|thinned]] hybrid black poplar ''([[populus|Populus x canadensis]])''. The last stage of the [[moss#Life cycle|moss lifecycle]] is shown, where the [[sporophyte]]s are visible before dispersion of their spores: the [[calyptra]] ('''1''') is still attached to the [[sporangium|capsule]] ('''3'''). The tops of the [[gametophytes]] ('''2''') can be discerned as well. Inset shows the surrounding, black poplars growing on sandy [[loam]] on the bank of a [[bog pond|kolk]], with the detail area marked.]]

In [[biology]], a '''spore''' is a unit of [[sexual reproduction|sexual]] (in fungi) or [[asexual reproduction]] that may be adapted for [[biological dispersal|dispersal]] and for survival, often for extended periods of time, in unfavourable conditions.<ref>{{Citation |last1=Setlow |first1=Peter |title=Spores and Their Significance |date=2014-04-30 |url=http://doi.wiley.com/10.1128/9781555818463.ch3 |work=Food Microbiology |pages=45–79 |editor-last=Doyle |editor-first=Michael P. |access-date=2023-12-13 |place=Washington, DC, USA |publisher=ASM Press |language=en |doi=10.1128/9781555818463.ch3 |isbn=978-1-68367-058-2 |last2=Johnson |first2=Eric A. |editor2-last=Buchanan |editor2-first=Robert L.|url-access=subscription }}</ref> Spores form part of the [[Biological life cycle|life cycles]] of many [[plant]]s, [[algae]], [[fungus|fungi]] and [[protozoa]].<ref>{{Cite web |url=http://tolweb.org/tree/home.pages/searchresults.html?cx=009557456284541951685%3A50nf_5tpvuq&cof=FORID%3A9&ie=UTF-8&q=spore&sa=Search |title=Tree of Life Web Project |access-date=5 February 2018 |archive-url=https://web.archive.org/web/20180205184645/http://tolweb.org/tree/home.pages/searchresults.html?cx=009557456284541951685%3A50nf_5tpvuq&cof=FORID%3A9&ie=UTF-8&q=spore&sa=Search |archive-date=5 February 2018 |url-status=dead }}</ref> They were thought to have appeared as early as the mid-late [[Ordovician]] period as an adaptation of early land plants.<ref name="Wellman-2000b">{{Cite journal |last1=Wellman |first1=C. H. |last2=Gray |first2=J. |date=2000-06-29 |title=The microfossil record of early land plants |journal=Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences |volume=355 |issue=1398 |pages=717–731; discussion 731–732 |doi=10.1098/rstb.2000.0612 |issn=0962-8436 |pmc=1692785 |pmid=10905606}}</ref>

[[Bacterial spore]]s are not part of a sexual cycle, but are resistant structures used for survival under unfavourable conditions.<ref>{{Cite book |last=Abel-Santos |first=Ernesto |title=Bacterial spores: current research and applications |date=2012 |publisher=Caister academic press |isbn=978-1-908230-00-3 |location=Norfolk}}</ref> [[Myxozoa]]n spores release amoeboid infectious germs ("amoebulae") into their hosts for parasitic infection, but also reproduce within the hosts through the pairing of two nuclei within the plasmodium, which develops from the amoebula.<ref>{{cite web|url=http://tolweb.org/Myxozoa/2460 |title=Myxozoa|archiveurl=https://web.archive.org/web/20150216140158/http://tolweb.org/Myxozoa/2460|archivedate=16 February 2015|work=Tree of Life Web Project|author=Ivan Fiala|date=10 July 2008|accessdate=14 January 2014|quote=Myxospores consist of several cells, which are transformed to shell valves, nematocyst-like polar capsules with coiled extrudible polar filaments and amoeboid infective germs.}}</ref>

In plants, spores are usually [[haploid]] and [[unicellular]] and are produced by [[meiosis]] in the [[sporangium]] of a [[diploid]] [[sporophyte]]. In some rare cases, a diploid spore is also produced in some algae, or fungi.<ref>{{Cite web |title=Diploid Spore - an overview {{!}} ScienceDirect Topics |url=https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/diploid-spore |access-date=2023-12-13 |website=www.sciencedirect.com |archive-date=13 December 2023 |archive-url=https://web.archive.org/web/20231213180708/https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/diploid-spore |url-status=live }}</ref> Under favourable conditions, the spore can develop into a new [[organism]] using [[mitosis|mitotic]] division, producing a [[multicellular]] [[gametophyte]], which eventually goes on to produce gametes. Two gametes fuse to form a [[zygote]], which develops into a new sporophyte. This cycle is known as [[alternation of generations]].

The spores of [[seed plant]]s are produced internally, and the megaspores (formed within the ovules) and the microspores are involved in the formation of more complex structures that form the dispersal units, the [[seed]]s and [[pollen]] grains.

==Definition==
The term ''spore'' derives from the [[ancient Greek]] word σπορά ''spora'', meaning "[[seed]], sowing", related to σπόρος ''{{lang|grc-Latn|sporos}}'', "sowing", and σπείρειν ''{{lang|grc-Latn|speirein}}'', "to sow".

In common parlance, the difference between a "spore" and a "[[gamete]]" is that a spore will germinate and develop into a [[sporeling]], while a gamete needs to combine with another gamete to form a zygote before developing further.

The main difference between spores and seeds as [[Biological dispersal|dispersal units]] is that spores are unicellular, the first cell of a gametophyte, while seeds contain within them a developing embryo (the multicellular sporophyte of the next generation), produced by the fusion of the male gamete of the pollen tube with the female gamete formed by the megagametophyte within the ovule. Spores germinate to give rise to haploid gametophytes, while seeds germinate to give rise to diploid sporophytes.

==Classification of spore-producing organisms==
{{anchor|homosporous|heterosporous}}

===Plants===
[[Vascular plant]] spores are always [[haploid]]. Vascular plants are either '''homosporous''' (also known as '''isosporous''') or '''[[Heterospory|heterosporous]]'''. Plants that are homosporous produce spores of the same size and type.

Heterosporous plants, such as [[seed plant]]s, [[spikemoss]]es, [[Isoëtes|quillworts]], and [[fern]]s of the order [[Salviniales]] produce spores of two different sizes: the larger spore (megaspore) in effect functioning as a "female" spore and the smaller (microspore) functioning as a "male". Such plants typically give rise to the two kind of spores from within separate sporangia, either a '''megasporangium''' that produces megaspores or a '''microsporangium''' that produces microspores. In flowering plants, these sporangia occur within the carpel and anthers, respectively.

===Fungi===
[[Fungus|Fungi]] commonly produce spores during sexual and asexual reproduction. Spores are usually [[haploid]] and grow into mature haploid individuals through [[mitosis|mitotic]] division of cells ([[Urediniospore]]s and [[Teliospore]]s among rusts are dikaryotic). [[Dikaryotic]] cells result from the fusion of two haploid gamete cells. Among sporogenic dikaryotic cells, karyogamy (the fusion of the two haploid nuclei) occurs to produce a diploid cell. Diploid cells undergo meiosis to produce haploid spores.{{citation needed|date=August 2024}}

==Classification of spores==
Spores can be classified in several ways such as by their spore producing structure, function, origin during life cycle, and mobility.

Below is a table listing the mode of classification, name, identifying characteristic, examples, and images of different spore species.
{| class="wikitable mw-collapsible mw-collapsed"
!Mode of Classification
! colspan="2" |Name
!Identifying Characteristic
!Example Spore Containing Organism
!Image
|-
| rowspan="10" |Spore Producing Structure
| colspan="2" |[[Sporangium|Sporangiospore]]
|Produced by [[sporangium]]
|[[Zygomycota|Zygomycetes]]
|[[File:Sporangium of fungi.jpg|thumb|Sporangium of Fungi]]
|-
| colspan="2" |[[Zygospore]]s
|Produced by [[zygosporangium]]
|[[Zygomycota|Zygomycetes]]
|[[File:Rhizopus_zygospores.jpg|thumb|Zygospores on [[Rhizopus oryzae|Rhizopus]]]]
|-
| colspan="2" |[[Ascus|Ascospores]]
|Produced by [[ascus]]
|[[Ascomycota|Ascomycetes]]
|[[File:Bitunicate_ascus_and_ascospores_of_Didymella_rabiei.png|thumb|Ascospores of ''[[Didymella rabiei|Didymella Rabiei]]'']]
|-
| colspan="2" |[[Basidiospore]]s
|Produced by [[basidium]]
|[[Basidiomycota|Basidiomycetes]]
|[[File:Basidium_schematic.svg|thumb|Typical reproductive structure of a [[Echigoshirayukidake (Basidiomycetes-X)|basidiomycete]], including the [[basidiospore]] and [[basidium]]]]
|-
| colspan="2" |[[Aeciospore|Aecispores]]
|Produced by [[aecium]]
|Rusts and Smuts
|[[File:Aecium sp.jpg|thumb|Aecia on foliage]]
|-
| colspan="2" |[[Urediniospore]]s
|Produced by uredinium
|Rusts and Smuts
|[[File:Puccinia thaliae urediniospores.jpg|thumb|Uredinospores]]
|-
| colspan="2" |[[Teliospore]]s
|Produced by [[Telium|teilum]]
|Rusts and Smuts
|[[File:Puccinia helianthi (teliospores).jpg|thumb|Microscopic image of teliospores]]
|-
| colspan="2" |[[Oospore]]s
|Produced by [[oogonium]]
|[[Oomycete]]s
|[[File:10554_oospore.jpg|thumb|Oospores of ''[[Kauri dieback|Phytophthora agathidicida]]'']]
|-
| colspan="2" |[[Carpospore]]s
|Produced by carposophorophyte
|[[Red algae|Red Algae]]
|[[File:Rhod1004.jpg|thumb|Light microscopy of ''[[Polysiphonia]]'' showing a carpospores and carposporophyte inside]]
|-
| colspan="2" |[[Tetraspore]]s
|Produced by [[Tetrasporaphyte|tetrasphorophyte]]
|[[Red algae|Red Algae]]
|[[File:Polysiphonia_tetraspores_WM2.jpg|thumb|Tetraspores of ''[[Polysiphonia]]'']]
|-
| rowspan="3" |Function
| colspan="2" |[[Chlamydospore|Chalmydospore]]
|Thick-walled [[resting spore]]s of fungi produced to survive in unfavorable conditions
|[[Ascomycota|Asomycota]]
|[[File:Candida_pseudohyphae,_chlamydospores,_blastospores.png|thumb|[[Hypha|Pseudohyphae]], chlamydospores and [[blastospore]]s of [[Candida (fungus)|''Candida'' yeast]].]]
|-
| rowspan="2" |Parasitic Fungal Spore
|Internal Spores
|Germinate within a host
|
| rowspan="2" |[[File:Pink_fungal_parasite_on_lichen_-_geograph.org.uk_-_1040204.jpg|thumb|A parasitic pink fungi on a [[Lichen]] tree]]
|-
|External (Environmental) spores
|Spores released by the host to infest other hosts <ref>{{Cite web |date=2008-06-26 |title=Biology of Microsporidia |url=http://www.modares.ac.ir/elearning/Dalimi/Proto/Lectures/week15/biology.htm |access-date=2024-03-24 |archive-url=https://web.archive.org/web/20080626082941/http://www.modares.ac.ir/elearning/Dalimi/Proto/Lectures/week15/biology.htm |archive-date=26 June 2008 }}</ref>
|
|-
| rowspan="3" |Origin During Life Cycle
| rowspan="2" |Meiospores
|[[Microspore]]s
|Produced sexually through [[meiosis]], and give rise to a male [[gametophyte]]
|[[Pollen]] in seed plants
|[[File:Microspore-formation.svg|thumb|In [[plant]]s, [[microspore]]s, and in some cases megaspores, are formed from all four products of meiosis.]]
|-
|[[Megaspore]]s (macrospores)
|Produced sexually through [[meiosis]], and give rise to a female [[gametophyte]]
|[[Ovule]] in seed plants
|[[File:Macrospore-formation.svg|thumb|In contrast, in many [[seed plant]]s and heterosporous [[fern]]s, only a single product of meiosis will become a [[megaspore]] (macrospore), with the rest degenerating.]]
|-
| colspan="2" |[[Conidium|Mitospores]]
|Produced asexually though [[mitosis]]
|[[Ascomycota|Ascomycetes]]
|[[File:Morchella conica 1 beentree.jpg|thumb|Ascomycete containing mitospores]]
|-
| rowspan="5" |Mobility
| colspan="2" |[[Zoospore]]s
|Mobile through [[Flagellum|flagella]]
|Some algae and fungi
|[[File:Zoospores - Reproductive Structure of the Phytophthora.png|thumb|Microscopic image of a Zoospore]]
|-
| colspan="2" |Aplanospores
|Immobile, however still produce flagella
|
|
|-
| colspan="2" |[[Autospore]]s
|Immobile spores that '''do not''' produce flagella
|
|[[File:Jenufa SAG 2383.jpg|thumb|Autospores of a strain of ''Jenufa aeroterrestrica'']]
|-
| colspan="2" |[[Ballistospore]]s
|Forcibly discharged from the fungal [[Sporocarp (fungus)|fruiting body]] due to internal force (such as built up pressure)
|Basidiospores and/or part of the genus ''Pilobus''
|[[File:Abb2.5 Fungi Basidiomycota basidium basidiospore ballistospore Bullers drop catapult mechanism 2021 (M. Piepenbring).png|thumb|Ballistospore mechanism of dispersal from fungi]]
|-
| colspan="2" |Stratismospores
|Forcibly discharged from the fungal [[Sporocarp (fungus)|fruting body]] due to external force (such as raindrops or passing animals)
|[[Puffball]]s
|[[File:Puff Balls - geograph.org.uk - 6255537.jpg|thumb|Puff Balls containing Stratismospores]]
|}

==External anatomy==
{{anchor|alete}}{{anchor|monolete}}{{anchor|trilete}}
[[File:Trilete spores.png|thumb|Fossil trilete spores (blue) and a spore tetrad (green) of [[Silurian|Late Silurian]] origin]]
[[File:Pollen Ricinus communis sanguineus.jpg|thumb|Tricolpate pollen of ''[[Ricinus]]'']]
Under high [[magnification]], spores often have complex patterns or ornamentation on their exterior surfaces. A specialized terminology has been developed to describe features of such patterns. Some markings represent apertures, places where the tough outer coat of the spore can be penetrated when germination occurs. Spores can be categorized based on the position and number of these markings and apertures. '''Alete spores''' show no lines. In '''monolete spores''', there is a single narrow line (laesura) on the spore.<ref name=PuntHoenBlacNils07>{{Cite journal |last1=Punt |first1=W. |last2=Hoen |first2=P. P. |last3=Blackmore |first3=S. |last4=Nilsson |first4=S. |last5=Le Thomas |first5=A. |date=2007 |title=Glossary of pollen and spore terminology |journal=Review of Palaeobotany and Palynology |volume=143 |issue=1 |pages=1–81 |doi=10.1016/j.revpalbo.2006.06.008 |bibcode=2007RPaPa.143....1P |name-list-style=amp }}</ref> Indicating the prior contact of two spores that eventually separated.<ref name="Wellman-2000b"/> In '''trilete spores''', each spore shows three narrow lines radiating from a center pole.<ref name=PuntHoenBlacNils07/> This shows that four spores shared a common origin and were initially in contact with each other forming a tetrahedron.<ref name="Wellman-2000b"/> A wider aperture in the shape of a groove may be termed a '''colpus'''.<ref name=PuntHoenBlacNils07/> The number of colpi distinguishes major groups of plants. [[Eudicots]] have '''tricolpate''' spores (i.e. spores with three colpi).<ref name=JuddOlms04>{{Cite journal |last1=Judd |first1=Walter S. |last2=Olmstead |first2=Richard G. |date=2004 |title=A survey of tricolpate (eudicot) phylogenetic relationships |journal=American Journal of Botany |volume=91 |issue=10 |pages=1627–44 |doi=10.3732/ajb.91.10.1627 |pmid=21652313 |name-list-style=amp |doi-access=free }}</ref>

===Spore tetrads and trilete spores===
{{Main|Evolutionary history of plants}}
Envelope-enclosed spore tetrads are taken as the earliest evidence of plant life on land,<ref name=Gray1985>{{cite journal
 | author = Gray, J.
 | year = 1985
 | title = The Microfossil Record of Early Land Plants: Advances in Understanding of Early Terrestrialization, 1970–1984
 | journal = [[Philosophical Transactions of the Royal Society B]]
 | volume = 309
 | issue = 1138
 | pages = 167–195
 | doi = 10.1098/rstb.1985.0077
 | last2 = Chaloner
 | first2 = W. G.
 | last3 = Westoll
 | first3 = T. S.
| jstor=2396358
 | bibcode=1985RSPTB.309..167G
| doi-access = free
 }}</ref> dating from the mid-Ordovician (early Llanvirn, ~{{Ma|470}}), a period from which no macrofossils have yet been recovered.<ref name=Wellman2000>{{cite journal
 | vauthors=Wellman CH, Gray J
 | year = 2000
 | title = The microfossil record of early land plants
 | journal = [[Philosophical Transactions of the Royal Society B]]
 | volume = 355
 | issue = 1398
 | pages = 717–732
 | doi = 10.1098/rstb.2000.0612
 | pmid = 10905606
 | pmc = 1692785
}}</ref>
Individual trilete spores resembling those of modern [[cryptogam]]ic plants first appeared in the fossil record at the end of the Ordovician period.<ref name="SteemansHerisse2009">{{cite journal|last1=Steemans|first1=P.|last2=Herisse|first2=A. L.|last3=Melvin|first3=J.|last4=Miller|first4=M. A.|last5=Paris|first5=F.|last6=Verniers|first6=J.|last7=Wellman|first7=C. H.|title=Origin and Radiation of the Earliest Vascular Land Plants|journal=Science|volume=324|issue=5925|year=2009|pages=353|issn=0036-8075|doi=10.1126/science.1169659|bibcode=2009Sci...324..353S|pmid=19372423|s2cid=206518080|url=https://biblio.ugent.be/publication/697223/file/709198.pdf|access-date=1 November 2017|archive-url=https://web.archive.org/web/20170922112350/https://biblio.ugent.be/publication/697223/file/709198.pdf|archive-date=22 September 2017|url-status=live|hdl=1854/LU-697223|hdl-access=free}}</ref>

==Dispersal==
[[File:Fungus spore ejection.ogg|thumb|Spores being ejected by fungi.]]

In fungi, both asexual and sexual spores or sporangiospores of many fungal species are actively dispersed by forcible ejection from their reproductive structures. This ejection ensures exit of the spores from the reproductive structures as well as travelling through the air over long distances. Many fungi thereby possess specialized mechanical and physiological mechanisms as well as spore-surface structures, such as [[hydrophobin]]s, for spore ejection. These mechanisms include, for example, forcible discharge of ascospores enabled by the structure of the ascus and accumulation of [[osmolyte]]s in the fluids of the ascus that lead to explosive discharge of the ascospores into the air.<ref name="Trail">{{cite journal|author=Trail F.|year= 2007|title=Fungal cannons: explosive spore discharge in the Ascomycota|journal=FEMS Microbiology Letters|volume=276|pages=12–8|pmid=17784861|doi=10.1111/j.1574-6968.2007.00900.x|issue=1|doi-access=free}}</ref>

The forcible discharge of single spores termed ''ballistospores'' involves formation of a small drop of water ([[Buller's drop]]), which upon contact with the spore leads to its projectile release with an initial acceleration of more than 10,000 [[G-force|g]].<ref name="Pringle et al.">{{cite journal|vauthors=Pringle A, Patek SN, Fischer M, Stolze J, Money NP |year= 2005|title=The captured launch of a ballistospore|journal=[[Mycologia]]|volume=97|pages=866–71|pmid=16457355|doi=10.3852/mycologia.97.4.866|issue=4}}</ref> Other fungi rely on alternative mechanisms for spore release, such as external mechanical forces, exemplified by [[puffballs]]. Attracting insects, such as flies, to fruiting structures, by virtue of their having lively colours and a putrid odour, for dispersal of fungal spores is yet another strategy, most prominently used by the [[stinkhorns]].

In Common Smoothcap moss (''[[Atrichum undulatum]]''), the vibration of sporophyte has been shown to be an important mechanism for spore release.<ref>Johansson, Lönnell, Sundberg and Hylander (2014) Release thresholds for moss spores: the importance of turbulence and sporophyte length. Journal of Ecology, n/a-n/a.</ref>

In the case of spore-shedding [[vascular plant]]s such as ferns, wind distribution of very light spores provides great capacity for dispersal. Also, spores are less subject to animal predation than seeds because they contain almost no food reserve; however they are more subject to fungal and bacterial predation. Their chief advantage is that, of all forms of progeny, spores require the least energy and materials to produce.

In the spikemoss ''[[Selaginella lepidophylla]]'', dispersal is achieved in part by an unusual type of [[diaspore (botany)|diaspore]], a [[tumbleweed]].<ref>{{cite web| title = False Rose of Jericho – Selaginella lepidophyllaFalse Rose of Jericho – Selaginella lepidophylla| work = Plant- and Flower guide| date = February 2009| url = http://www.plant-and-flower-guide.com/rose-of-jericho.html| access-date = 1 February 2010| archive-url = https://web.archive.org/web/20110715092118/http://www.plant-and-flower-guide.com/rose-of-jericho.html| archive-date = 15 July 2011| url-status = live}}</ref>

== Origin ==
Spores have been found in [[microfossil]]s dating back to the mid-late [[Ordovician]] period.<ref name="Wellman-2000b"/> Two hypothesized initial functions of spores relate to whether they appeared before or after land plants. The heavily studied hypothesis is that spores were an adaptation of early land plant species, such as [[embryophyte]]s, that allowed for plants to easily disperse while adapting to their non-aquatic environment.<ref name="Wellman-2000b" /><ref name="Norem-1958">{{Cite journal |last=Norem |first=W. L. |date=1958 |title=Keys for the Classification of Fossil Spores and Pollen |url=https://www.jstor.org/stable/1300785 |journal=Journal of Paleontology |volume=32 |issue=4 |pages=666–676 |jstor=1300785 |issn=0022-3360}}</ref> This is particularly supported by the observation of a thick spore wall in [[cryptospore]]s. These spore walls would have protected potential offspring from novel weather elements.<ref name="Wellman-2000b" /> The second more recent hypothesis is that spores were an early predecessor of land plants and formed during errors in the [[meiosis]] of [[algae]], a hypothesized early ancestor of land plants.<ref name="Strother-2021">{{Cite journal |last1=Strother |first1=Paul K. |last2=Foster |first2=Clinton |date=2021-08-13 |title=A fossil record of land plant origins from charophyte algae |url=https://www.science.org/doi/10.1126/science.abj2927 |journal=Science |language=en |volume=373 |issue=6556 |pages=792–796 |doi=10.1126/science.abj2927 |pmid=34385396 |bibcode=2021Sci...373..792S |issn=0036-8075|url-access=subscription }}</ref>

Whether spores arose before or after land plants, their contributions to topics in fields like [[paleontology]] and plant [[phylogenetics]] have been useful.<ref name="Strother-2021" /> The spores found in microfossils, also known as cryptospores, are well preserved due to the fixed material they are in as well as how abundant and widespread they were during their respective time periods. These microfossils are especially helpful when studying the early periods of earth as macrofossils such as plants are not common nor well preserved.<ref name="Wellman-2000b" /> Both cryptospores and modern spores have diverse morphology that indicate possible environmental conditions of earlier periods of Earth and evolutionary relationships of plant species.<ref name="Wellman-2000b" /><ref name="Strother-2021" /><ref name="Norem-1958" />

==Gallery==
<gallery>
File:Bartramia ithyphylla sporen.jpeg|Spores of the [[moss]] ''Bartramia ithyphylla''. (microscopic view, 400x)
File:Fernspore1.jpg|Dehisced fern sporangia. (microscopic view, no spores are visible)
File:Botbrush1.jpg|Spores and elaters from a horsetail. (''[[Equisetum]]'', microscopic view)
File:Trilete spores.png|Fossil plant spores (''[[Scylaspora]]'') from Silurian deposits of Sweden.
File:Unknown fruit mold with spores methylene blue x2000.jpg|Fruit mold with spores and distinguishable cellular growth. (2000x)
File:Reticularia olivacea-1.jpg|Spore clusters, formed inside sporangia of the slime mold ''[[Reticularia olivacea]]'', from pine forests of eastern [[Ukraine]].
File:Tubifera dudkae-4.jpg|Internal surface of the [[peridium]] of the slime mold ''Tubifera dudkae'' with spores.
</gallery>

==See also==
{{Portal|Fungi}}
* [[Aeroplankton]]
* [[Auxiliary cell]]
* [[Bioaerosol]]
* [[Cryptospore]]

==References==
{{Reflist}}

{{Botany}}

{{Authority control}}

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