R114 Proconsul site (Miocene of Kenya)

Also known as Kiakanga Hill; Rusinga, R114, Whitworth's Pothole

Where: Kenya (0.3° S, 34.1° E: paleocoordinates 1.5° S, 32.0° E)

• coordinate stated in text

• small collection-level geographic resolution

When: Okowe Member (Kiahera Formation), Burdigalian (20.4 - 16.0 Ma)

• "Lower Miocene... The [Rusinga] Group itself was probably deposited in less than half a million years, and five Potassium-Argon dates for the Group give a mean age of 17.9 +/- 0.16 Ma (Drake et al., 1988). The Hiwegi Formation and site R114 have not been directly dated."

•Michel et al. 2023: One particularly important result from this work is confirmation of R114's position in the Kiahera Formation (Pickford, 1984) instead of the Hiwegi Formation (cf. Van Couvering, 1972;Whitworth, 1953).

• group of beds-level stratigraphic resolution

Environment/lithology: "floodplain"; lithified, tuffaceous, green siltstone

• "the infilling of a standing dead, hollow tree trunk. Pyroclastic sediments of the Hiwegi Formation up to several meters in depth were washed around standing trees on the slopes of the ancient volcano of Kisingiri"

•sediments were "reworked by shallow, sluggish streams and redeposited in a floodplain environment" according to Clos 1995

• "The infilling green grits are easily differentiated from the surrounding grey tuffaceous flagstones and agglomerates because they are fenetized. Fenite... is commonly found around carbonate volcanic instrustions"

•"grey tuffaceous siltstone" according to Clos 1995

Size class: macrofossils

Collected by L. S. B. Leakey in 1951, 1984

• "Leakey broke blocks of rock from the pipe and removed those that had bones showing"

Primary reference: J. Arroyo-Cabrales, R. Gregorin, D. A. Schlitter and A. Walker. 2002. The oldest African molossid bat cranium (Chiroptera: Molossidae). Journal of Vertebrate Paleontology 22(2):380-387 [J. Alroy/J. Alroy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 84800: authorized by John Alroy, entered by John Alroy on 11.11.2008

Creative Commons license: CC BY (attribution)

Taxonomic list

Mammalia
 Primates -
"Proconsul heseloni n. sp." = Ekembo heseloni
"Proconsul heseloni n. sp." = Ekembo heseloni Walker et al. 1933 ape
 Chiroptera - Molossidae
Tadarida rusingae n. sp. Arroyo-Cabrales et al. 2002 free-tailed bat
Reptilia
 Squamata - Varanidae
Varanus rusingensis n. sp. Clos 1995 monitor lizard