Chaetocladus

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Chaetocladus
Temporal range: Middle Ordovician - Devonian[1]
Chaetocladus holotype loduca1997.PNG
The holotype of Chaetocladus plumula (USNM 41 137, from LoDuca 1997)
Scientific classification
Kingdom: Plantae
Phylum: Chlorophyta
Class: Ulvophyceae
Order: Dasycladales
Pascher 1931
Family: Triploporellaceae
LoDuca 1997
Tribe: Salpingoporelleae
LoDuca 1997
Subtribe: Chaetocladinae
LoDuca 1997
Genus: Chaetocladus
Whitfield 1894 emend LoDuca 1997
Species
  • C. gracilis
Kenrick & Vither 2006
  • C. ruedemanni
LoDuca 1997
  • C. dubius
LoDuca 1997
  • C. plumula
Whitfield 1894
  • C. hefteri
Kra¨usel and Weyland, 1962

Chaetocladus is a non-calcifying genus of unicellular green alga known from the Upper Silurian.

Morphology[edit]

Chaetocladus thalli range from 2–6 cm in height and average 1 cm in diameter.[2] They comprise a parallel-sided, unbranching axis which is surrounded by leaf-like ramifications.

Fossil record[edit]

Chaetocladus is known from upper Silurian konservat lagerstatte, and found in association with other algae, arthropods, and annelid worms.[2] Similar Dasycladean algae are reported from late-Ordovician lagerstatte.[3]

Classification[edit]

Due to its morphological similarity to the extant order Dasycladales, Chaetocladus is considered to be an early cousin of this order. Unlike the majority of Dasycladales, Chaetocladus does not form deposit calcite - therefore it required much rarer taphonomic conditions to be preserved.[4] Some genera now recognised as Chaetocladus were originally described as Graptolites.[5]

References[edit]

  1. ^ LoDuca, S.T.; Kluessendorf, J.; Mikulic, D.G. (2003). "A New Noncalcified Dasycladalean Alga From The Silurian Of Wisconsin". Journal of Paleontology 77 (6): 1152–1158. doi:10.1666/0022-3360(2003)077<1152:ANNDAF>2.0.CO;2. 
  2. ^ a b LoDuca, S.T. (1997). "The Green Alga Chaetocladus (Dasycladales)". Journal of Paleontology 71 (5): 940–949. JSTOR 1306570. 
  3. ^ Young, G.A.; Rudkin, D.M.; Dobrzanski, E.P.; Robson, S.P.; Nowlan, G.S. (2007). "Exceptionally preserved Late Ordovician biotas from Manitoba, Canada". Geology 35 (10): 883–886. doi:10.1130/G23947A.1. 
  4. ^ Kenrick, P.; Vinther, J. (2006). "Chaetocladus gracilis n. sp., a non-calcified Dasycladales from the Upper Silurian of Skåne, Sweden". Review of Palaeobotany and Palynology 142 (3–4): 153–160. doi:10.1016/j.revpalbo.2006.03.023. Retrieved 2007-10-10. 
  5. ^ e.g. LoDuca, S.T. (1990). "Medusaegraptus mirabilis Ruedemann as a Noncalcified Dasyclad Alga". Journal of Paleontology 64 (3): 469–474. JSTOR 1305597.