Icaronycteris

Icaronycteris; Temporal range: Early Eocene PreꞒ Ꞓ O S D C P T J K Pg N
	Icaronycteris index, Green River Formation, in the ROM,
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Chiroptera
Family:	†Icaronycteridae
Genus:	†Icaronycteris; Jepsen 1966
Species
	†Icaronycteris index; Jepsen 1966; †Icaronycteris? menui; Russell, Louis & Savage 1973; †Icaronycteris sigei; Smith et al. 2007;

Icaronycteris is an extinct genus of microchiropteran (echolocating) bat that lived in the early Eocene, approximately 52.2 million years ago, making it the earliest known definitive bat.[1] Four exceptionally preserved specimens, among the best preserved bat fossils, are known from the Green River Formation of North America.[1] There is only one thoroughly described species of bat in the genus, I. index,[2] although fragmentary material from France has also been tentatively placed within Icaronycteris as the second species I. menui.[3] I. sigei is based on well-preserved fragments of dentaries and lower teeth found in Western India.[4]

Icaronycteris index, Houston

Description

Icaronycteris[5] measured about 14 centimetres (5.5 in) long and had a wingspan of 37 centimetres (15 in). It closely resembled modern bats, but had some primitive traits. The tail was much longer and not connected to the hind legs with a skin membrane, the first wing finger bore a claw and the body was more flexible. Similarly, it had a full set of relatively unspecialised teeth, similar to those of a modern shrew. Its anatomy suggests that, like modern bats, Icaronycteris slept while hanging upside down, holding onto a tree branch or stone ridge with its hind legs.[6]

Phylogeny

According to Simmons & Geisler 1998,[7] Icaronycteris is the first genus, followed by Archaeonycteris, Hassianycetris, and Palaeochiropteryx, in a series leading to extant microchiropteran bats.[8]

←

Megachiroptera

Icaronycteris

Archaeonycteris

	Palaeochiropteryx

	Microchiroptera (Echolocating bats)

[9]

References

Notes

Gunnell & Simmons 2005, Fossil Bats, p. 214
Jepsen 1966
Simmons & Geisler 1998, p. 40
Smith et al. 2007, Abstract
The name relates the mythic flight of Icarus to Nycteris, the genus of "hollow-faced bats".
Palmer 1999, p. 211
Simmons & Geisler 1998, Abstract
Simmons & Conway 1998, Discussion of Phylogenetic Relationships
Simmons & Conway 1998

Sources

Gunnell, G. F.; Simmons, N. B. (2005). "Fossil evidence and the origin of bats" (PDF). Journal of Mammalian Evolution. 12 (1–2): 209–246. doi:10.1007/s10914-005-6945-2.
Jepsen, G. L. (1966). "Early Eocene bat from Wyoming". Science. 154 (3754): 1333–9. Bibcode:1966Sci...154.1333J. doi:10.1126/science.154.3754.1333. PMID 17770307.
Palmer, D., ed. (1999). The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals. London: Marshall Editions. ISBN 978-1-84028-152-1.
Russell, D. E.; Louis, P.; Savage, D. E. (1973). "Chiroptera and Dermoptera of the French early Eocene". University of California Publications in Geological Sciences. 95: 1–57. OCLC 691130847.
Smith, T.; Rana, R. S.; Missiaen, P.; Rose, K. D.; Sahni, A.; Singh, H.; Singh, L. (2007). "High bat (Chiroptera) diversity in the Early Eocene of India". Naturwissenschaften. 94 (12): 1003–1009. Bibcode:2007NW.....94.1003S. doi:10.1007/s00114-007-0280-9. hdl:1854/LU-385394. PMID 17671774.
Simmons, N. B.; Conway, T. (1998). "Chiroptera". Tree of Life. Retrieved 1 September 2014.
Simmons, N. B.; Geisler, J. H. (1998). "Phylogenetic relationships of Icaronycteris, Archaeonycteris, Hassianycteris, and Palaeochiropteryx to extant bat lineages, with comments on the evolution of echolocation and foraging strategies in Microchiroptera" (PDF). Bulletin of the AMNH (235).