thumb|300px|Hand sample of the Rhynie chert from [[Rhynie, Aberdeenshire|Rhynie, Scotland.]]
The Rhynie chert is a Lower Devonian sedimentary deposit exhibiting extraordinary fossil detail or completeness (a Lagerstätte). It is exposed near the village of Rhynie, Aberdeenshire, Scotland; a second unit, the Windyfield chert, is located some 700 m away.
The Rhynie chert contains exceptionally preserved plant, fungus, lichen and animal material places it at an early stage in the colonisation of land. Second, these cherts are famous for their exceptional state of ultrastructural preservation, with individual cell walls easily visible in polished specimens. Stomata have been counted and lignin remnants detected in the plant material, and the breathing apparatus of trigonotarbids—of the class Arachnida—(known as book lungs) can be seen in cross-sections. Fungal hyphae can be seen entering plant material, acting as decomposers and mycorrhizal symbionts.
For these reasons the Rhynie chert has been designated a Site of Special Scientific Interest (SSSI) by NatureScot.
Location
The bed is under at least 1 metre of overburden, in a small field near the village of Rhynie, so is effectively inaccessible to collectors; besides which, the site is a Site of Special Scientific Interest. A second unit, the Windyfield chert, is some 700 m from the Rhynie. The Rhynie chert extends for at least 80 m along strike and 90 m down-dip.
Until recently, the Rhynie chert was the only such deposit known from the geological record, although recent work has turned up other localities from different time periods and continents.
Conditions of formation
The chert was formed when silica-rich water from volcanic springs rose rapidly and petrified the early terrestrial ecosystem, in situ and almost instantaneously, interbedded with sands, shales and tuffs - which speak of local volcanic activity. Deposition was very rapid. river flowing to the north periodically deposited the sandy layers found in cores when it flooded its banks.
Sedimentary textures which appear to have formed in the hydrothermal vents themselves are preserved with a brecciated texture;
Preservation
Plants
thumb|Surface view of a polished piece of Rhynie chert showing many cross-sections of Rhynia stems (axes). Scale bar is 1 cm.
right|thumb|Thin section of a piece of Rhynie chert viewed by transmitted light showing the cross-section of a stem of Rhynia
The preservation of plants varies from perfect three-dimensional cellular permineralisation to flattened charcoal films. On occasion, plants may have their vertical axes preserved in growth position, with rhizoids still attached to rhizomes; even the plant litter is preserved. The analysis of rhizomes and rhizoids makes it possible to discern which plants had an active water uptake system (e.g. Horneophyton), and which were likely to have colonised waterlogged surfaces (Asteroxylon). The chert also allows the identification of the gametophyte phases of taxa such as Aglaophyton.
Analysis of spores shows that the flora was lacking in some elements common elsewhere at this time, likely due to its setting in a mountainous region, rather than in a lowland flood plain like most other fossil deposits.
- Aglaophyton
- Asteroxylon
- Horneophyton
- Nothia
- Rhynia
- Trichopherophyton
- Ventarura
Another group, Nematophytes, remains enigmatic, but may represent aquatic land plants.
Algae
Several putative chlorophytes have been discovered in the Rhynie assemblage (Mackiella and Rhynchertia). A well-preserved charophyte, Palaeonitella,
Arthropods
As a result of its exquisite preservation, the Rhynie chert boasts the most diverse non-marine fauna of its time, Typical members of the Rhynie chert arthropod fauna include the crustacean Lepidocaris, the euthycarcinoid Heterocrania, the springtail Rhyniella, the possible insect Leverhulmia, the harvestman Eophalangium sheari, Acari (mites), the centipede Crussolum and trigonotarbids in the genus Palaeocharinus.
The oldest known hexapod (Rhyniella praecursor), which resembles the modern springtails, was found in the Rhynie chert, pushing dates for the origination of hexapods (a group that includes the insects) back to the Silurian period.
Fungi
Fungi known from the Rhynie chert include the chytridiomycetes, ascomycetes, oomycota (Peronosporomycetes) and glomeromycetes; The fossils are filamentous, around 3 μm in diameter, and grew on plants and the sediment itself. They occasionally form structured colonies which go on to create microbial mats.
Lichens
A new genus of lichen, Winfrenatia, has been recovered from the Rhynie chert. The lichen comprises a thallus, made of layered, aseptate hyphae; a number of depressions are formed on its top surface. Each depression contains a net of hyphae holding a sheathed cyanobacterium. The fungus appears to be related to the Zygomycetes, and the photobiont resembles the coccoid Gloeocapsa and Chroococcidiopsis.
Paleobiota
Animals
{| class="wikitable sortable mw-collapsible"
! colspan="6" align="center" |Animals
|-
!Genus
!Species
!Higher taxon
!Notes
!Images
|-
|Palaeocharinus
|
- P. rhyniensis
- P. tuberculatus
|Trigonotarbida
|Likely a predatory liquid-feeder
|thumb|center|P. rhyniensis reconstruction
|-
|Palaeocteniza
|
- P. crassipes
|Trigonotarbida
|Only fossil material comes from a moulted juvenile
|
|-
|Eophalangium
|
- E. sheari
|Tetrophthalmi
|Preserves oldest tracheae in fossil record
|
|-
|Protacarus
|
- P. crani
|Alycidae
|All other mites in the Rhynie chert have been synonymised with this species
|
|-
|Crussolum
|
- C. sp
|Scutigeromorpha
|Too poorly preserved to assign to a species
|thumb|center|Reconstruction of a Crussolum leg
|-
|Rhynimonstrum
|
- R. dunlopi
|Arthropoda incertae sedis
|Possibly a myriapod, if so likely a millipede
|thumb|center|Specimen of Rhyniognatha
|-
|Leverhulmia
|
- L. mariae
|Myriapoda or Hexapoda
|Affinities controversial
|
- L. rhyniensis
|Branchiopoda
|Only member of Lipostraca
|thumb|center|Reconstruction of Lepidocaris
|-
|Castracollis
|
- C. wilsonae
|Branchiopoda
|Stem-calmanostracan (related to tadpole shrimp)
|thumb|center|Reconstruction of Castracollis
|-
|Ebullitiocaris
|
- E. oviformis
|Diplostraca?
|Soft tissue unknown, only known from valves
|
|-
|Palaeonema
|
- P. phyticum
|Enoplida
|Earliest nematode in the fossil record
|Unapplicable
|Gnathifera
|Undescribed
|
|-
|}
Plants and Multicellular Algae
{| class="wikitable sortable mw-collapsible"
! colspan="6" align="center" |Plants and Algae
|-
!Genus
!Species
!Higher taxon
!Notes
!Images
|-
|style="background:#D1FFCF;" |Asteroxylon
|style="background:#D1FFCF;" |
- A. mackiei
|style="background:#D1FFCF;" |Drepanophycales
|style="background:#D1FFCF;" |Infected by parasitic root fungi
|style="background:#D1FFCF;" |thumb|center|Asteroxylon life restoration
|-
|style="background:#D1FFCF;" |Aglaophyton
|style="background:#D1FFCF;" |
- A. major
|style="background:#D1FFCF;" |Polysporangiophytes
|style="background:#D1FFCF;" |Preserves earliest known mycorrhizal fungi
|style="background:#D1FFCF;" |
- N. aphylla
|style="background:#D1FFCF;" |Zosterophylls?
|style="background:#D1FFCF;" |May have been poisonous to fend off arthropods?
|style="background:#D1FFCF;" |thumb|center|Reconstruction of Nothia
|-
|style="background:#D1FFCF;" |Rhynia
|style="background:#D1FFCF;" |
- R. gwynne-vaughanii
|style="background:#D1FFCF;" |Rhyniophytina
|style="background:#D1FFCF;" |Gametophyte preserved, named Remyophyton (although another form may exist)
|style="background:#D1FFCF;" |thumb|center|Reconstruction of Rhynia
|-
|style="background:#D1FFCF;" |Trichopherophyton
|style="background:#D1FFCF;" |
- T. teuchansii
|style="background:#D1FFCF;" |Zosterophylls?
|style="background:#D1FFCF;" |Unusually bore spines on its stems.
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Palaeonitella
|style="background:#D1FFCF;" |
- P. cranii
|style="background:#D1FFCF;" |Charales
|style="background:#D1FFCF;" |Fungi preserved colonising this alga
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Mackiella
|style="background:#D1FFCF;" |
- M. rotundata
|style="background:#D1FFCF;" |Ulotrichaceae
|style="background:#D1FFCF;" |Preserves possible chloroplasts
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Rhynchertia
|style="background:#D1FFCF;" |
- R. punctata
|style="background:#D1FFCF;" |Ulotrichaceae
|style="background:#D1FFCF;" |Some specimens preserved with zoospores inside cells
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Cymatiosphaera
|style="background:#D1FFCF;" |
- Unapplicable
|style="background:#D1FFCF;" |Pyramimonadales?
|style="background:#D1FFCF;" |Not assigned to a species, may be an indeterminate chlorophyte alga. may be an indeterminate chlorophyte alga.
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Xanthophyta indet.
|style="background:#D1FFCF;" |
- Unapplicable
|style="background:#D1FFCF;" |Ochrophytina
|style="background:#D1FFCF;" |First definitive xanthophyte in the fossil record?
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Phaeophyceae indet?
|style="background:#D1FFCF;" |
- Unapplicable
|style="background:#D1FFCF;" |Ochrophytina
|style="background:#D1FFCF;" |Possible oldest brown alga in the fossil record
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Characrhynium
|style="background:#D1FFCF;" |
- C. amoenum
|style="background:#D1FFCF;" |Diaphoretickes incertae sedis
|style="background:#D1FFCF;" |Resembles both modern Characium and Characiopsis
|style="background:#D1FFCF;" |
|-
|}
Fungi
{| class="wikitable sortable mw-collapsible"
! colspan="6" align="center" |Fungi
|-
!Genus
!Species
!Higher taxon
!Notes
!Images
|-
|style="background:#D1FFCF;" |Archaeosporites
|style="background:#D1FFCF;" |
- A. rhyniensis
|style="background:#D1FFCF;" |Archaeosporaceae
|style="background:#D1FFCF;" |Incredibly similar to Archaeospora
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Brijax
|style="background:#D1FFCF;" |
- B. amictus
|style="background:#D1FFCF;" |Chytridiomycota
|style="background:#D1FFCF;" |Placement within the group uncertain, colonises glomeromycote spores
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Cultoraquaticus
|style="background:#D1FFCF;" |
- C. trewini
|style="background:#D1FFCF;" |Chytridiomycota
|style="background:#D1FFCF;" |Epibiotic on enigmatic round structures
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Frankbaronia
|style="background:#D1FFCF;" |
- F. polyspora
- F. velata
|style="background:#D1FFCF;" |Oomycetes?
|style="background:#D1FFCF;" |Second known oomycete fossil
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Globicultrix
|style="background:#D1FFCF;" |
- G. nugax
|style="background:#D1FFCF;" |Chytridiomycota
|style="background:#D1FFCF;" |Is itself a parasite of larger fungal spores
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Glomites
|style="background:#D1FFCF;" |
- G. sporocarpoides
- G. rhyniensis
|style="background:#D1FFCF;" |Glomerales
|style="background:#D1FFCF;" |Formed mycorrhizae in various land plants
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Hassiella
|style="background:#D1FFCF;" |
- H. monospora
|style="background:#D1FFCF;" |Oomycetes
|style="background:#D1FFCF;" |First known oomycete fossil
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Helmutella
|style="background:#D1FFCF;" |
- H. devonica
|style="background:#D1FFCF;" |Fungi incertae sedis
|style="background:#D1FFCF;" |Resembles Carboniferous "sporocarps"
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Illmanomyces
|style="background:#D1FFCF;" |
- I. corniger
|style="background:#D1FFCF;" |Chytridiomycota
|style="background:#D1FFCF;" |Grows on various other spores, fungal matter, plants and algae.
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Krispiromyces
|style="background:#D1FFCF;" |
- K. discoides
|style="background:#D1FFCF;" |Endochytriaceae
|style="background:#D1FFCF;" |Parasite of Palaeonitella, grows inside cells
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Kryphiomyces
|style="background:#D1FFCF;" |
- K. catenulatus
|style="background:#D1FFCF;" |Fungi incertae sedis
|style="background:#D1FFCF;" |Preserved inside a glomeromycote spore
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Lyonomyces
|style="background:#D1FFCF;" |
- L. pyriformis
|style="background:#D1FFCF;" |Fungi incertae sedis
|style="background:#D1FFCF;" |Grows on cells of Palaeonitella
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Mycokidstonia
|style="background:#D1FFCF;" |
- M. sphaerialoides
|style="background:#D1FFCF;" |Ambisporaceae
|style="background:#D1FFCF;" |Previously thought to be an ascomycete
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Nimbosphaera
|style="background:#D1FFCF;" |
- N. rothwellii
|style="background:#D1FFCF;" |Chytridiomycota
|style="background:#D1FFCF;" |Likely zoosporangia of chytrids
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Palaeoendogone
|style="background:#D1FFCF;" |
- P. gwynne-vaughaniae
|style="background:#D1FFCF;" |Mucoromycotina
|style="background:#D1FFCF;" |Endophyte of Horneophyton
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Palaeomyces
|style="background:#D1FFCF;" |
- P. agglomeratus
- P. asteroxyli
- P. gordonii
- P. horneae
- P. simpsoni
|style="background:#D1FFCF;" |Mucoromycota
|style="background:#D1FFCF;" |Grows on/within land plant stems
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Palaeozoosporites
|style="background:#D1FFCF;" |
- P. renaultii
|style="background:#D1FFCF;" |Chytridiomycota?
|style="background:#D1FFCF;" |Root parasite of Asteroxylon
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Perexiflasca
|style="background:#D1FFCF;" |
- P. tayloriana
- P. ventricosa
|style="background:#D1FFCF;" |Chytridiomycota
|style="background:#D1FFCF;" |Grew on land plant remains
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Potteromyces
|style="background:#D1FFCF;" |
- P. asteroxylicola
|style="background:#D1FFCF;" |Ascomycota incertae sedis
|style="background:#D1FFCF;" |Plant pathogen of Asteroxylon
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Prototaxites
|style="background:#D1FFCF;" |
- P. taiti
|style="background:#D1FFCF;" |Fungi incertae sedis
|style="background:#D1FFCF;" |Affinities debated in a 2025 preprint
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Retesporangicus
|style="background:#D1FFCF;" |
- R. lyonii
|style="background:#D1FFCF;" |Blastocladiomycota incertae sedis
|style="background:#D1FFCF;" |Earliest known fungus with multiple sporangia per hyphae
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Rhizophidites
|style="background:#D1FFCF;" |
- R. matryoshkae
- R. shutae
|style="background:#D1FFCF;" |Chytridiomycota
|style="background:#D1FFCF;" |Grew within Horneophyton and glomeromycote spores
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Rhyniomycelium
|style="background:#D1FFCF;" |
- R. endoconidiarum
|style="background:#D1FFCF;" |Ascomycota?
|style="background:#D1FFCF;" |Oldest fossil evidence of endoconidia in fungi.
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Rhyniovexator
|style="background:#D1FFCF;" |
- R. penetrans
|style="background:#D1FFCF;" |Chytridiomycota or Aphelida
|style="background:#D1FFCF;" |Parasitic on unicellular algae
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Scepasmatocarpion
|style="background:#D1FFCF;" |
- S. fenestrulatum
|style="background:#D1FFCF;" |Fungi incertae sedis
|style="background:#D1FFCF;" |One of the oldest hyphal investments found
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Scutellosporites
|style="background:#D1FFCF;" |
- S. devonicus
|style="background:#D1FFCF;" |Gigasporaceae
|style="background:#D1FFCF;" |Bears a germination shield, a feature shared only with the extant Scutellospora
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Trewinomyces
|style="background:#D1FFCF;" |
- T. annulifer
|style="background:#D1FFCF;" |Fungi incertae sedis
|style="background:#D1FFCF;" |Grew on decaying plant matter
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Veterisphaera
|style="background:#D1FFCF;" |
- V. dumosa
|style="background:#D1FFCF;" |Fungi incertae sedis
|style="background:#D1FFCF;" |Has a two-layered hyphal mantle
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Windipila
|style="background:#D1FFCF;" |
- W. spinifera
- W. wimmervoecksii
- W. pumila
|style="background:#D1FFCF;" |Fungi incertae sedis (Glomeromycota?)
|style="background:#D1FFCF;" |Bears unusual spines and projections from the mantle
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Zwergimyces
|style="background:#D1FFCF;" |
- Z. vestitus
|style="background:#D1FFCF;" |Fungi incertae sedis
|style="background:#D1FFCF;" |Only "mantled" fungal fossil with preserved development
|style="background:#D1FFCF;" |
|-
|}
Other taxa
{| class="wikitable sortable mw-collapsible"
! colspan="6" align="center" |Other taxa
|-
!Genus
!Species
!Higher taxon
!Notes
!Images
|-
|style="background:#D1FFCF;" |Palaeoleptochlamys
|style="background:#D1FFCF;" |
- P. hassi
|style="background:#D1FFCF;" |Arcellinida
|style="background:#D1FFCF;" |One of the earliest known testate amoebae
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Triskelia
|style="background:#D1FFCF;" |
- T. scotlandica
|style="background:#D1FFCF;" |Eukaryota incertae sedis
|style="background:#D1FFCF;" |Either a green algae or a fungus.
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Rhyniotaenium
|style="background:#D1FFCF;" |
- R. velatum
|style="background:#D1FFCF;" |Mesotaeniaceae
|style="background:#D1FFCF;" |Likely a saccoderm desmid
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Anechosoma
|style="background:#D1FFCF;" |
- A. oblonga
|style="background:#D1FFCF;" |Archaeplastida incertae sedis
|style="background:#D1FFCF;" |Unclear whether it belongs to Glaucophyta or Chlorophyta, hosts the fungus Rhyniovexator
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Langiella
|style="background:#D1FFCF;" |
- L. scourfieldii
|style="background:#D1FFCF;" |Hapalosiphonaceae
|style="background:#D1FFCF;" |Synonymised with Kidstonia and Rhyniella
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Archaeothrix
|style="background:#D1FFCF;" |
- A. contexta
- A. oscillatoriformis
|style="background:#D1FFCF;" |Oscillatoriales
|style="background:#D1FFCF;" |Colonised lesions on Aglaophyton
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Rhyniococcus
|style="background:#D1FFCF;" |
- R. uniformis
|style="background:#D1FFCF;" |Chroococcaceae
|style="background:#D1FFCF;" |Forms sheets one cell thick,
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Eoentophysalis
|style="background:#D1FFCF;" |
- E. sp.
|style="background:#D1FFCF;" |Entophysalidaceae
|style="background:#D1FFCF;" |Otherwise only known from the Proterozoic
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Rhyniosarcina
|style="background:#D1FFCF;" |
- R. devonica
|style="background:#D1FFCF;" |Chroococcales
|style="background:#D1FFCF;" |Forms sarcinoid colonial structures
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Palaeolyngbya
|style="background:#D1FFCF;" |
- P. kerpii
|style="background:#D1FFCF;" |Oscillatoriaceae
|style="background:#D1FFCF;" |Other species within the genus are known from the Precambrian
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Croftalania
|style="background:#D1FFCF;" |
- C. venusta
|style="background:#D1FFCF;" |Oscillatoriales incertae sedis
|style="background:#D1FFCF;" |Common mat-forming cyanobacterium
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Rhyniotaxillus
|style="background:#D1FFCF;" |
- R. devonicus
- R. minutulus
|style="background:#D1FFCF;" |Cyanobacteria incertae sedis
|style="background:#D1FFCF;" |Small coccoid cyanobacteria, resembles Entophysalis
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Rhystigonema
|style="background:#D1FFCF;" |
- R. obscurum
|style="background:#D1FFCF;" |Stigonemataceae
|style="background:#D1FFCF;" |May be assignable to Stigonema itself
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Winfrenatia
|style="background:#D1FFCF;" |
- W. reticulata
|style="background:#D1FFCF;" |Zygomycota, Chroococcaceae
|style="background:#D1FFCF;" |Lichen composed of a fungus, coccoid cyanobacterium
|style="background:#D1FFCF;" |thumb|center|Reconstructed transverse view of Winfrenatia
|-
|style="background:#D1FFCF;" |Nematoplexus
|style="background:#D1FFCF;" |
- N. rhyniensis
|style="background:#D1FFCF;" |Nematophyta
|style="background:#D1FFCF;" |Member of the enigmatic nematophytes
|style="background:#D1FFCF;" |
|-
|style="background:#D1FFCF;" |Nematothallus
|style="background:#D1FFCF;" |
- N. sp
|style="background:#D1FFCF;" |Nematophyta
|style="background:#D1FFCF;" |Only known from one specimen, previously only known from compressions
|style="background:#D1FFCF;" |
|-
|}
Interactions
The Rhynie chert, by preserving a snapshot of an ecosystem in situ in high fidelity, gives a unique opportunity to observe interactions between species and kingdoms. wounds in various states of repair, and the mouthparts of arthropods. In addition, a fossil enoplid nematode named Palaeonema parasitised Aglaophyton plants, with eggs, juveniles and adults all recorded from within their stomatal chambers.
Coprolites - fossilised droppings - give a useful insight of what animals ate, even if the animals cannot be identified. Coprolites found in the Rhynie chert are typically between 0.5 and 3 mm in size, and contain a variety of contents. Analysis of coprolites allows the identification of different feeding modes, including detritovory and herbivory; some coprolites are so densely packed with spores that it is possible that these made up a substantial proportion of some organisms' diets. it is possible for many of the arthropods to deduce their likely ecological role, however, it is unclear if this community was representative of a typical terrestrial arthropod community of the time, or rather was specific to the stressed Rhynie environment.
Plants responded to fungal colonisation in different ways, depending on the fungus. The rhizoids of Nothia displayed three responses to fungal infestation: the hyphae of some (mutualistic) colonists were encased by plant cell walls; other (parasitic) fungi were met with typical host responses of increased rhizome cell size; while yet other fungi solicited an increase in thickness and pigmentation of cell walls. Once inside a plant cell, fungi produced spores, which are found in decaying plant cells;
See also
- Evolutionary history of plants
- Geology of Scotland