Africa

Only two Early Jurassic mammals, both morganucodon-tans (chapter 4), are known from Africa, but they are represented by extraordinary specimens: each is based on a nearly complete skull and skeleton from the southern part of the continent (figure 2.6). Two occurrences in Lesotho are in the Red Beds of the Stormberg Group, which is the source for a remarkable fauna of terrestrial vertebrates, including a remarkable diversity of therapsids. The Red Beds and the remainder of the Stormberg Group above the Molteno Beds are regarded as being of Early Jurassic (Lias-sic) age (see Clemens et al., 1979; Clemens, 1986, and references therein). The third occurrence is from the Elliot Formation, also in the Lower Jurassic part of the Storm-berg Group (Olsen and Galton, 1984).

Megazostrodon rudnerae is a large, Morganucodon-like mammal, placed by some with Docodonta (e.g., McKenna and Bell, 1997). It differs from Morganucodon in its pattern of molar occlusion (Crompton and Jenkins, 1968; Crompton, 1974). Megazostrodon was first described from the Pokane locality in Lesotho. A second specimen, con figure 2.6. Mesozoic mammal sites of Africa and Madagascar. Asterisks, Early (black; localities 1-3), Middle (gray; locality 8), and Late (white; locality 4) Jurassic; diamonds, Early (black; localities 5, 6) and Late (gray; localities 7,9) Cretaceous. Localities or local faunas: 1, Pokane; 2, Mafeteng (Red Beds of the Stormberg Group; Early Jurassic, Lesotho); 3, Gertruida Farm (Elliott Formation; Early Jurassic, Orange Free State, South Africa); 4, Tendaguru (Tendaguru Beds; Kimmeridgian-Tithonian, Tanzania); 5, Koum Basin (Grès de Gaba Member, Koum Formation; Barremian, Cameroon); 6, Synclinal d'Anoual (Séquence B des Couches Rouges; Berriasian, Morocco); 7, Draa Ubari (Mizdah Formation; Santonian-Campanian, Libya); 8, Ambondromamay (Isalo level IlIb, Isalo "Group"; Bathonian, Madagascar); 9, Berivotra (Maeverano Formation; Maastrichtian, Madagascar).

figure 2.6. Mesozoic mammal sites of Africa and Madagascar. Asterisks, Early (black; localities 1-3), Middle (gray; locality 8), and Late (white; locality 4) Jurassic; diamonds, Early (black; localities 5, 6) and Late (gray; localities 7,9) Cretaceous. Localities or local faunas: 1, Pokane; 2, Mafeteng (Red Beds of the Stormberg Group; Early Jurassic, Lesotho); 3, Gertruida Farm (Elliott Formation; Early Jurassic, Orange Free State, South Africa); 4, Tendaguru (Tendaguru Beds; Kimmeridgian-Tithonian, Tanzania); 5, Koum Basin (Grès de Gaba Member, Koum Formation; Barremian, Cameroon); 6, Synclinal d'Anoual (Séquence B des Couches Rouges; Berriasian, Morocco); 7, Draa Ubari (Mizdah Formation; Santonian-Campanian, Libya); 8, Ambondromamay (Isalo level IlIb, Isalo "Group"; Bathonian, Madagascar); 9, Berivotra (Maeverano Formation; Maastrichtian, Madagascar).

sisting of a distorted but nearly complete skull with associated vertebrae, was described by Gow (1986a), from the Gertruida Farm near Clocolan, Orange Free State. The second specimen is of interest in that it documents replacement of molariform teeth in Megazostrodontidae and in that it has a so-called pseudangular process on the jaw, a feature also seen in North American Dinnetherium (see Jenkins et al., 1983). Erythrotherium parringtoni, based on a specimen of a young individual (Crompton, 1964b), is from the Mafeteng locality. The dental and skeletal anatomy of both Megazostrodon and Erythro-

therium have been described and analyzed in great detail (Crompton and Jenkins, 1968; Crompton, 1974; Jenkins and Parrington, 1976).

Trackways possibly belonging to mammals are also known from the Stormberg Group in Lesotho (see Clemens et al., 1979, and references therein). A variety of footprint types, some with possible traces of hair, were described by Ellenberger (e.g., 1972,1974,1975) and referred to various groups of Mesozoic mammals. As noted by Sarjeant (2000), the affinities of these ichnotaxa remain debatable.

Archaeodon reuningi, based on a supposed jaw fragment with part of a tooth from the Late Triassic of Namibia, was previously thought to be a possible mammal, but restudy of the specimen showed it to be of nonorganic origin (Hopson and Reif, 1981).

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