Red Hill Palynology (plant spores)
Palynology is the study of the microscopic, decay-resistant — but non-mineral (i.e., composed of chitin and sporopollenin) — remains of animals, plants and fungi. Within paleontology, these remains (palynomorphs) are typically used for biostratigraphy (using fossil organisms to determine the relative age of geologic deposits), but they have sometimes proved useful in sedimentology, paleoecology and paleoclimatology. There is a wide variety of marine palynomorphs (e.g., acritarchs, dinoglagellates and foraminiferans), but palynomorphs of terrestrial origin typically consists of either the spores or pollen of vascular plants.
A palynological study of Red Hill indicated that the site belongs to the VH (verrucosa-hystricosus) palynological zone, which is referable to the upper Fa2c part of the Upper Famennian (Late Devonian). The absolute age is estimated to be 361 million years.
Red Hill yielded a relatively rich palynoflora. At least 11 palynomorphs have been identified at Red Hill. Aneurospora greggsii, Auroaspora macara, Geminospora sp., Grandispora echinata, Rugospora flexosa and Vallatosporites hystricosus were common to dominant in most samples. Another taxon, Retusotriletes communis, was dominant in one sample but absent elsewhere.
| Taxon | 95-12 | 94-1 | 94-2 | CL | PH |
|---|---|---|---|---|---|
| Aneurospora greggsii | D | C | C | - | + |
| Apiculiretuispora sp. | + | - | - | - | - |
| Auroraspora macara | D | - | D | D | + |
| Geminospora sp. | D | - | C | D | + |
| Grandispora echinata | D | + | C | D | - |
| Lophozonotriletes excisus | + | + | + | + | - |
| Retusotriletes spp. | + | + | + | - | - |
| Rugospora flexosa | D | D | D | + | + |
| Spinozontriletes? sp. | - | + | + | - | - |
| Vallatosporites hystricosus | + | D | D | + | - |
Alfred Traverse, who conducted this study at Red Hill, suspects that further investigations may yield interesting ecological and sedimentological information. He cited a study by Maurice Streel and Stephen Scheckler (1990) that reported distinctive palynofloras from an upstream alluvial deposit (Rawley Springs, Virginia) and a deltaic site (Elkins, West Virginia), both of which were similar in age (Fa2c) to Red Hill.
One problem with using palynology in paleoecological studies is the unresolved systematics of some taxa. For instance, Traverse (2003) commented that it is difficult to differentiate Geminospora and Aneurospora, while Rugospora flexuosa and Auroraspora exhibited considerable variability in both size and morphological details.
Another problem is that palynomorphs are often not assignable to "mother plants". In fact, its possible for morphologically similar palynomorphs to belong to unrelated plants. There are, however, some exceptions relevant to Red Hill. Fairon-Demaret et. al. (2001) assigned miospores of the Geminospora - Aneurospora complex to the arborescent progymnosperm, Archaeopteris. Similarily, Streel and Scheckler (1990) suspected that Aneurospora greggsii belonged to Archaeopteris. They also suspected that Auroraspora asperella (synonomized by the authors in part with Auroraspora macra) belonged to an arborecent lycopsid and concluded that the miospores of the Diducites plicabilis-Auroaspora varia complex are attributable to the fern Rhacophyton.
There is some correspondence at Red Hill between the abundance of certain palynomorphs and their "mother plants." Two abundant palynomorphs, Aneurospora greggsii and Geminospora sp. are assignable to Archaeopteris, which accounted for nearly half of the recognizable macrofossils at Red Hill. The possible assignment of Auroraspora macara with arborescent lycopsids is also notable given that palynomorphs abundance. On the other hand, palynomorphs belonging to the Diducites plicabilis - Auroaspora varia complex were not reported from Red Hill even though Rhacophyton was co-dominant with Archaeopteris. Interestingly, these palynomorphs accounted for only 4% of the miospores at Rawley Springs, even though Rhacophyton was abundant at that site, whereas they were often dominant in the deltaic sediments at Elkins.
Three dominant Red Hill palynomorphs, Grandispora echinata, Rugospora flexosa and Vallatosporites hystricosus, are not assignable to any macrofossils (only Vallatosporites hystricosus was dominant in the sites studied by Streel and Scheckler). Whether these originated from nearby "mother plants" growing in microhabitats where they are less likely to be fossilized remains to be seen.
- Web:
- Klaus-Peter Kelber's palynology links for palaeobotanists:
www.uni-wuerzburg.de/mineralogie/palbot/palynology/palynology.html - Palaeos.com's webpage on palynology:
www.palaeos.com/Palaeo/Palynology.html - Peter Davis' palynology website:
www.geo.arizona.edu/palynology/ - U.S. Gological Survey on pollen and spore palynology:
geology.er.usgs.gov/paleo/sporepollen.shtml - Books:
- Traverse, A. 1988. Paleopalynology. Boston: Allen and Unwin.
- Scientific Papers:
- Fairon-Demaret, M. I. Leponce, and M. Streel. 2001. "Archaeopteris from the Upper Famennian of Belgium: heterospory, nomenclature, and paleogiogeography." Rev. Paleobot. Palynol. 115(1-2: 79-97.
- Streel, M., and S. E. Scheckler. 1990. "Miospore lateral distribution in upper Famennian alluvial lagoonal to tidal facies from eastern United States and Belgium." Review of Palaeobotany and Palynology 64: 315–324.
- Traverse, A. 2003. "Dating the earliest tetrapods: A Catskill palynological problem in Pennsylvania." Cour. Forsch. -Inst. Senckenberg 241:19-29.