Monodactyl Equids from Konso, Interval 1

Earlier Fauna, Interval 1, KGA 4 locality, around 1.9 My old

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Metacarpals
There are six fragments, KGA 4-359, KGA 4-1801, and KGA 4-2179 and (Fig. 1). The diaphysis of KGA 4-2179 is abnormally flat. Its distal dimensions as well as that of KGA 4-1801 are much smaller than in KGA 4-359.
As much as it is possible to guess, KGA 4-359 resembles KNM ER 1276 of Notochoerus scotti faunal zone (NS) at Koobi Fora referred to Allohippus sp. (in an article on this web-site) and FLK I 507-573 from Olduvai Bed I. Another fragment, KGA 10-698, could belong the same species but its age is much younger, only about 1.4 My. Among extant species, the closest in proportions is E. africanus (Fig. 2), but it is much smaller.
The other MC III are more flat in the diaphysis, a character usually associated with robustness.

Metatarsal
Three proximal fragments differ from each other (Fig. 3) .One of them, KGA 4-2381 seems similar to KNM ER 4052 and 5338 from NS zone at Koobi Fora (Fig. 4). These MT resemble those of extant Wild Asses. The other two have also relatively deep diaphyses.

Tali
The closest resemblance I could find for these two tali are two specimens from Olduvai Bed I (Fig. 5).

Calcanea
There are five specimens.

Phalanges
– There are two first phalanges (Ph1) one of which, KGA 4M-1537 has dimensions so bizarre that it cannot be of use. KGA 4M,CA7-2031 is a robust phalanx, possibly anterior, with a wide proximal end. It has the same proportions as Tih 630 of Tihodaà¯ne (Fig. 6).

– There is also a second posterior phalanx (Ph 2P), KGA 4M-2032,CA7, resembling one Ph2P of Tighenif – probably E. mauritanicus (Fig. 7).

To summarize :
There is evidence for two forms of during Interval 1 : one reminding of Wild Asses ; the other with wider and flatter diaphyses and deep distal keels.