. Bonner zoologische Beiträge : Herausgeber: Zoologisches Forschungsinstitut und Museum Alexander Koenig, Bonn. Biology; Zoology. 158 W. Haacke. Fig. 8: Distribution of the three subspecies of Typhlacontias punctatissimus in the northern Namib Desert. tion of a relationship with Scelotes and he assumes that Typhlacontias evolved in arid areas of southern Africa, with T brevipes, due to the presence of external limb rudiments and a relatively large postnasal scale, as the most primitive form. In the light of Broadley's (1968) evaluation of evolutionary trends in the acontine scincid genus Typhl
. Bonner zoologische Beiträge : Herausgeber: Zoologisches Forschungsinstitut und Museum Alexander Koenig, Bonn. Biology; Zoology. 158 W. Haacke. Fig. 8: Distribution of the three subspecies of Typhlacontias punctatissimus in the northern Namib Desert. tion of a relationship with Scelotes and he assumes that Typhlacontias evolved in arid areas of southern Africa, with T brevipes, due to the presence of external limb rudiments and a relatively large postnasal scale, as the most primitive form. In the light of Broadley's (1968) evaluation of evolutionary trends in the acontine scincid genus Typhlosaurus, one may have to re-evaluate Greer's suggestion. A number of morphological characters of the eight taxa are listed in Tables 1 and 2. The presence or absence of the very large second (= fused second and third?) lower labial in combination with the presence of prefrontals separates this genus into two groups. T. brevipes, T. johnsonii and T. punctatissimus, have this large second lower labial, but no prefrontal and are Namib Desert endemics (Figs 6, 7, 8), while T gracilis, T. rohani and T. rudebecki sp. n. have no fused lower labials but a prefrontal above the supraoculars. The first two species of the latter group are widespread in Kalahari sand with high rainfall at fairly high altitude above sea level (Fig. 7). In contrast the presence of T. rudebecki, of which the range is still unknown, on the northern Namib coast at sea level is not yet understood. Broadley (1968: 18) lists three trends in Typhlosaurus Wiegmann (Acontinae), which imply degrees of evolutionary advancement or a greater degree of specialisa-. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Zoologisches Forschungsinstitut und Museum Alexander Koenig. Bonn : Das Forschungsinstitut
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