Orillas del Humuya (Pleistocene of Honduras)

Where: Honduras (14.5° N, 87.7° W: paleocoordinates 14.5° N, 87.7° W)

• coordinate based on nearby landmark

When: Late/Upper Pleistocene (0.1 - 0.0 Ma)

• The age of the Orillas del Humuya local fauna is very probably late Pleistocene (Rancholabrean). The mammoth is represented by two broken molars, both bearing compressed and very narrow plates. The better specimen, UF 17728, is probably a first lower molar, with at least eight plates, crown height exceeding 115 mm, width of about 85 mm, and plate frequency of 8 per 100 mm. This is an advanced species of mammoth, possibly as old as late Irvingtonian, but more probably Rancholabrean.

Environment/lithology: terrestrial; tuffaceous, gray sandstone

• The exposed sediments attain a thickness of about 15 m, the upper two-thirds consisting of massive reddish-brown , fine to medium tuffaceous sands. The lower third is capped by a well cemented gray, fine tuffaceous sandstone unit about 0.5 m thick. The quarries that produced concentrations of fossils were dug into the lower 3 m near the dry season river level in cross-bedded , light gray, pebbly tuffaceous channel sands that rest unconformably on Tertiary ignimbrites. In the vicinity, Cretaceous conglomeratic red beds of the Valle de Angeles Formation are also exposed unconformably below the Pleistocene alluvium.

Size class: macrofossils

Collection methods: University of Florida

Primary reference: S. D. Webb and S. C. Perrigo. 1984.  Late Cenozoic Vertebrates from Honduras and El Salvador. Journal of Vertebrate Paleontology 4(2):237-254 [J. Alroy/J. Alroy/J. Ju]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 190753: authorized by Evangelos Vlachos, entered by Evangelos Vlachos on 16.12.2017

Creative Commons license: CC BY (attribution)

Taxonomic list

Reptilia
 Testudines - Pangeoemydidae
Rhinoclemmys sp. Fitzinger 1835 turtle
UF 17722
Mammalia
 Notoungulata - Toxodontidae
Mixotoxodon larensis Van Frank 1957 notoungulate
UF 12257
 Rodentia - Caviidae
Hydrochoerus sp. Brisson 1762 capybara
UF 17723
 Lagomorpha - Leporidae
Sylvilagus sp. Gray 1867 cottontail rabbit
UF 17724
 Perissodactyla - Equidae
Equus sp. Linnaeus 1758 horse
UF 17730
 Xenarthra - Megalonychidae
Megalonyx sp. Harlan 1825 edentate
UF 32100
 Xenarthra - Megatheriidae
Eremotherium sp. Spillmann 1948 edentate
UF 18044
 Proboscidea - Elephantidae
Mammuthus cf. columbi Falconer 1857 Columbian mammoth
UF 17728