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Cordylus angolensis (Bocage, 1895) was described 128 years ago on the basis of a single specimen collected at Caconda in the west-central highlands of Angola. Additional specimens referred to this species were collected at 'Mombolo' (also in the central highlands) during the Vernay Angola Expedition in 1925. As the holotype was apparently destroyed in the fire of 1978 at the Museu Bocage in Lisbon and no additional specimens have been collected, its taxonomic status and phylogenetic relationships has remained uncertain. The species has eluded all efforts aimed at its re-discovery in the vicinity of the type locality, with a single specimen from near Condé, north of Mombolo—collected in 1970 by Wulf Haacke—the only other specimen of Cordylus known from west-central Angola. Recent field work in the Angolan highlands resulted in the collection of a series of specimens from Taqueta Mountain (west of Caconda), Monte Verde (Sandula, 'Mombolo') and Uassamba (Vondo). A phylogenetic analysis, using three mitochondrial and six nuclear genes, indicated the existence of two distinct species-level lineages in the Angolan highlands. These two species are allopatric and morphologically distinct, differing especially in terms of their colour patterns, eye colour and certain scalation characteristics. We therefore confirm that C. angolensis is a valid species and designate a neotype, and describe a new species, Cordylus momboloensis sp. nov.

Five snake, four lizard, nine amphibian (all anurans) and three fish species were recorded in the Apline grasslands of the Sehlabathebe National Park, South-Eastern Lesotho, Southern Africa. They include rare, threatened and endemic species, some of which are restricted to the Drakensberg / Maloti region. The following species were recorded: snakes Lamprophis aurora, L. fuscus, Hemachatus haemachatus, Bitis arietans, B. atropos; lizards Trachylepsis punctatissima, Tropidosaura montana, Pseudocordylus melanotus, Afroedura nivaria; amphibians (anurans) Xenopus laevis laevis, Bufo gariepensis nubicolus, Cacosternum striatum, Amietia dracomontana, A. angloensis, A. fuscigula, A. umbraculata, Strongylopus fasciatus, Semnodactylus wealii; fishes Labeobarbus aeneus, Pseudobarbus quathlambae and Oncorhynchus mykiss. Species with high conservation priorities include: Lamprophis fuscus, Tropidosaura cottrelli, Pseudocordylus spinosus, Amietia umbraculata, A. drakomontana, Strongylopus fasciatus and Pseudobarbus quathlambae.

To elucidate the functional significance of the three distinct types of generation glands that have been identified among cordylid lizards, we mapped gland type to the terminal taxa in the most recent phylogenetic tree for the Cordylidae. We used the phylogenetic programme Mesquite and applied the principle of parsimony to infer character states for the ancestral nodes in the tree. For those species where information on gland type was not available from the literature, we conducted a histological investigation of generation gland morphology, using standard histological techniques. We included two species of the sister family Gerrhosauridae in the analysis to serve as outgroups. In both Gerrhosaurus typicus and G. flavigularis, scales immediately anterior to the femoral pores displayed glandular activity, but differed from generation glands of cordylids in the absence of mature glandular generations. Among the cordylids investigated, we identified a fourth type of generation gland in Pseudocordylus subviridis, P. spinosus, and in the two Hemicordylus species, one where the glands consistently comprise of two mature glandular generations. In H. capensis, both single- and two-layer type glands are present. Our reconstruction of ancestral character states suggests a minimum of six transformations from one gland type to another during the evolutionary history of the family. The reconstruction furthermore suggests that the single-layer type gland reappeared at least once (in Hemicordylus) in the Cordylinae after having been lost. The reconstruction also unequivocally shows that the pit-like multiple-layer type gland evolved directly from the single-layer type and not from the protruding multiple-layer type. The two-layer type gland appears to be an intermediary condition between the multiple-layer and single-layer types. The evolutionary transformation of generation gland type appears to be linked to changes in lifestyle and associated changes in degree of territoriality and the need for chemical communication.

Girdled lizards (Cordylidae) are sub-Saharan Africa's only endemic squamate family and contain 80 nominal taxa, traditionally divided into four genera: Cordylus, Pseudocordylus, Chamaesaura and Platysaurus. Previous phylogenetic analysis revealed Chamaesaura and Pseudocordylus to be nested within Cordylus, and the former genera were sunk into the later. This taxonomic revision has received limited support due to the study's poor taxon sampling, weakly supported results and possible temporary nomenclatural instability. Our study analyzes three nuclear and three mitochondrial genes from 111 specimens, representing 51 in-group taxa. Parsimony, likelihood and Bayesian analyses of concatenated and partitioned datasets consistently recovered a comb-like tree with 10, well-supported, monophyletic lineages. Our taxonomic reassessment divides the family into 10 genera, corresponding to these well-supported lineages. Short internodes and low support between the non-platysaur lineages are consistent with a rapid radiation event at the base of the viviparous cordylids.

We investigated the thermoregulatory abilities and behavior of Pseudocordylus melanotus melanotus (Drakensberg crag lizard) in terms of the relationship between the operative temperature (Te), selected temperature (Tsel), set-point range (Tset) and field active body temperature (field Tsel), exposure to low temperature, body posture and activity. The Te range for P. m. melanotus was about 58 C (23.20 C in winter to 54.94 C in summer). In a laboratory thermal gradient, in a setting that is independent of ecological costs or thermal constraints, lizards maintained Tset (defined as the interquartile range of Tsel, after Hertz et al., 1993) between 29.00 6 0.36 C and 31.78 6 0.16 C in winter and 29.61 6 0.28 C and 32.47 6 0.18 C in summer. The mean Tsel was 30.08 6 0.14 C in winter and 30.99 6 0.11 C in summer. In the field, however, lizards achieved significantly lower Tb, which suggests that the thermal environment limited the Tb that lizards were able to achieve. Lizards were active for significantly longer and selected significantly higher Tb in summer than in winter. During winter, lizards spent a significant amount of time at Tb below their lower critical limiting temperature (defined by loss of righting). The most frequently assumed body postures in summer were those where the head or body were raised, whereas, in winter, lizards usually lay with head and body flat on the rock substrate. We suggest that these differences reflect the physiological requirements of the lizards: Head-up postures in sit-and-wait foragers are consistent with scanning for prey while head-down postures are likely motivated by thermoregulatory needs. It is clear that P. m. melanotus can thermoregulate efficiently, but the Tb maintained may be constrained by the range of Te available to the lizards in their natural environment. Pseudocordylus m. melanotus currently appears to be geographically constrained by low environmental temperatures at the edge of its range. Should global warming become a reality in southern Africa, this species could inadvertently benefit by occupying new habitat that was previously unavailable because of thermal constraints.

1. An organism's thermal tolerance to the environment may indicate a thermal limit to its geographical distribution. 2. We measured the lower critical minimum (CTMin) and lower lethal temperature in the lizard Pseudocordylus melanotus melanotus . 3. CTMin was 10.17±0.48 °C and the lower lethal temperature was −5.15±0.31 °C. 4. All lizards that froze did not survive. This suggests that these lizards are restricted to areas where the microclimate allows them to avoid freezing. 5. Pseudocordylus m. melanotus can allow their body temperatures to drop well below CTMin without any ill effect.

A new haemogregarine species Hepatozoon affluomaloti sp. n. is described from erythrocytes in the peripheral blood of crag lizards Pseudocordylus melanotus (Smith) and Pseudocordylus subviridis (Smith) (Sauria: Cordylidae) from mountainous regions in the Eastern Free State, South Africa. This species can be distinguished from all other congeners based on its large size, staining properties and life cycle development in its vector, Culex (Afroculex) lineata (Theobald) (Diptera: Culicidae). Mature gamonts stain mostly uniformly pinkish-purple with Giemsa, sometimes containing darker azurophilic granules anterior and posterior to the nucleus. The reflexed posterior extremity of the gamont stage sometimes stains slightly deeper purple and the nucleus is dense and placed in the posterior third of the parasite body. Merogonic stages of this haemogregarine occur in the liver tissues of P. melanotus with dizoic meronts. Macromeronts contains 2-7 macromerozoites and micromeronts contains 9-24 micromerozoites. Sporogonic developmental stages found in the proposed final host and vector, C. lineata, include large oocysts, measuring 54 × 48 µm on average. Sporulating oocysts with 8 nuclei are present in mosquitoes 6-7 days post-feeding on infected lizards. Sporocysts with mature sporozoites measure 31.0 × 21.8 µm on average and each contains 2-8 large sporozoites. It is suggested that transmission of infective sporozoites is achieved through predation of lizards on mosquitoes.

The first quantitative data on foraging mode in the cordyliform lizards reveal different foraging behaviours between and within families. All species of cordylids studied (four Cordylus, two Pseudocordylus. and one Platysaurus) are ambush foragers. However, the species of Cordylus and Pseudocordylus microlepidotus are the most extreme ambushers. These species spent a significantly lower per cent time moving than did all of the other species studied and made significantly fewer movements per minute than Platysaurus capensis and gerrhosaurids. In addition, P. microlepidotus made significantly fewer movements per minute than did its congener Pseudocordylus capensis. Possible reasons for the high number of movements per minute in Platysaurus capensis are discussed. Very limited observations of two gerrhosaurid species show that Cordylosaurus subtessellatus is an active forager and Gerrhosaurus validus forages actively at least some of the time. A tentative hypothesis of the evolution of cordyliform foraging behaviour based on very limited data hints that active foraging is plesiomorphic in the Gerrhosaurini and further that gerrhosaurids may have retained active foraging from the common ancestor of Scincidae and Cordyliformes. Somewhat stronger data suggest that ambush foraging arose in the common ancestor of Cordylidae or Cordylinae. Further study is needed to trace inter- and intrageneric changes in foraging mode in cordylids.

Abstract We examined the reproductive cycles of two species of the only oviparous genus Platysaurus in the predominantly viviparous family Cordylidae, endemic to Southern Africa. The reproductive cycles of Platysaurus capensis and P. minor were determined using data obtained from field caught and museum specimens. Males of both species exhibit testicular recrudescence during autumn (April-May) and maximum testicular volumes together with peak spermiogenic activity occur during winter through early summer (July-November). Small testicular volumes associated with testicular regression occur during mid-summer (December) through early autumn (March). Similarly, females of both species begin vitellogenesis in autumn, culminating in ovulation during spring (September-October). Females are ovigerous in summer (November through December). Clutch size is fixed on two eggs. In both species, male and female cycles are well synchronised. The fact that the autumn/winter ovarian cycles of these oviparous lizards correspond to that of viviparous members of the family Cordylidae adds to the data that suggest that the oviparous mode of reproduction in the genus Platysaurus represents one of the few known cases of an evolutionary reversal from the derived viviparous mode. Along with the viviparity-oviparity reversal a postnuptial-prenuptial testicular cycle reversal is suggested. Data presented in this paper support the hypothesis that the ancestral oviparous Platysaurus evolved on the Mozambique lowlands from a viviparous montane Pseudocordylus ancestor.

Abstract A new crag lizard of the genus Pseudocordylus is described from the Western Cape Province, South Africa. It is an archaic melanistic form, occurring in sympatry with other archaic melanistic lizard and mollusc taxa within the mistbelt of the Hottentotsholland Mountains, part of the Cape Folded Mountains. With a maximum snout-vent length of less than 80 mm, it has an exceptionally small body size for a crag lizard. It has a conservative morphology which bridges the morphological gap that exists between Pseudocordylus and Cordylus. It is suspected that this species has a very restricted range in the Hottentotsholland Mountains, and that indiscriminate burning of the veld and collecting of the species may pose a serious threat to its survival.

EXTENDED ABSTRACT Reproduction in the viviparous lizard, Pseudocordylus m. melanotus, is distinctly seasonal. Females exhibit autumn/winter vitellogenic activity, with ovulation occurring during July-September. Females are gravid during the late winter-spring period and parturition follows in early summer (December), with 1–6 young being produced. Males exhibit a basic pre-nuptial spermatogenic cycle. Testicular recrudescence begins in summer, followed by peak size and spermiogenesis in late summer/early autumn, and testicular regression during winter and spring. Males become reproductively active during a period of increasing ambient temperature and photoperiod, whereas these environmental parameters declined during the onset of vitellogenesis in females.

Mitochondrial DNA sequences were obtained for 16 species representing all nominal genera of Cordylidae (Platysaurus, Chamaesaura, Cordylus, and Pseudocordylus). Gerrhosauridae and Teiidae were used as first and second outgroups. Results indicate that the oviparous Platysaurus is the sister taxon of the remaining cordylids (all of which are ovoviviparous). Within the ovoviviparous group Cordylus is paraphyletic with respect to Chamaesaura and Pseudocordylus. No evidence of Pseudocordylus monophyly was discovered. The three species of Chamaesaura and the seven species of Pseudocordylus are transferred to Cordylus to render a monophyletic taxonomy.

The distribution of the adrenaline and noradrenaline chromaffin cells in the adrenal glands of 10 members of the family Cordylidae have been examined. In the genus Gerrhosaurus, all the catecholamine cells lie on the surface of the adrenal gland, forming a continuous envelope of one or two layers of cells that mainly contain noradrenaline (NA). In the genus Platysaurus, the chromaffin envelope is intermittent. There are relatively large tracts of interspersed interrenal tissue containing some adrenaline cells (A). Islets of chromaffin cells are scattered between these interrenal tracts. In the genus Pseudocordylus and the genus Cordylus, the superficial chromaffin cells tend to gather into a multilayered dorsal mass, containing mainly NA cells. Inside the interrenal parenchyma, there are always numerous chromaffin islets, containing mainly A cells.