South African Specimens Research Articles

The status ofBathyporeia gracilisSars (Amphipoda, Haustoriidae)

Abstract The haustoriid amphipod, Bathyporeia gracilis Sars, is a valid species, primarily characterized by the short antennae of the male. The species is diagnosed and partially illustrated on the basis of the male syntype, and some specimens from the Irish Sea, collected by Jones (1948). The South African specimens currently ascribed to B. gracilis, in fact belong to an undescribed species, related to B. tenuipes Meinert.

FURTHER ARCHIANNELIDS FROM SOUTHERN AFRICA

Summary Archiannelids of the family Nerillidae belonging to the genus Nerilla, are recorded for the first time from sandy beaches of the Republic of South Africa. A generic key and list of the seven known species is given. The genus Nerilla is discussed and the terminology assigned to certain appendages is clarified and related to those of Polychaetes. The South African specimens are identified as Nerilla antennata O. Schmidt. A brief account of their habitat and structure is included.

The anatomy of the thecodont reptile Euparkeria capensis Broom

The South African Museum specimens of Euparkeria originally described by Broom (1913 a, b ) and later studied by Haughton (1922) have been further prepared using the dental mallet. In addition, material in Professor D. M. S. Watson’s collection has been prepared and studied. As a result of inquiries made at Aliwal North, it is suggested that all the material may represent a single find and a small exposure of Cynognathus zone shale close to the town is considered to be the most probable location of the site. On the basis of the specimens already mentioned a detailed description of most of the skeleton is given, the only parts remaining unknown, or incompletely known, being the carpus and manus, the braincase and the caudal vertebrae. The following features are discussed in functional terms: skull architecture; the limbs and their girdles; the vertebral column and ribs. The skull, although showing some adaptation to predacious habits, is relatively unspecialized and a subsequent reversal of trend towards a more omnivorous or even vegetarian diet is not impossible. A consideration of the probable arrangement of the jaw muscles suggests that the antorbital fenestra of the archosaurs was not originally evolved in relation to the development of the pterygoideus D musculature. A study of the limbs and their girdles indicates that Euparkeria was facultatively bipedal and that when this gait was adopted the femora were brought into a vertical position, although they must have been held horizontally while at rest or moving slowly. It is suggested that the alteration in position of the rib articulations along the length of the vertebral column is related to efficiency of pulmonary ventilation. Expansion of the tips of the neural spines is shown to be related not to the development of dermal armour but to the arrangement of the muscles of the transversospinalis system. The term ‘scute tables’ used to designate these expansions is therefore abandoned and they are referred to simply as spine tables. The relationships of Euparkeria to other groups is briefly discussed. Euparkeria shows a number of progressive features related to a highly carnivorous habit and increased locomotor efficiency combined with retention of several primitive characters. Previous authors have tended to lay emphasis on one or other of these types of characteristic and accordingly classify Euparkeria either as an advanced form or as a very primitive one: the consequent variation in proposed systematic position ranges from inclusion in the Sphenosuchidae (v. Huene 1962) to the Erythrosuchidae (Hughes 1963). It is concluded that Euparkeria , although a progressive form, is closely related to the latter family with which it may be convenient, for the time being, to classify it. It could well have been directly ancestral to advanced pseudosuchians such as Ornithosuchus and Hesperosuchus and possibly to the prosauropods and sauropods but not to the ornithischians or the birds and was a trifle too advanced to have been directly ancestral to the Aëtosauridae, to which it is, however, closely related.

Notes on Tropical African Juncaceae

Adamson (Journ. Linn. Soc. Bot. 50: 5 (I935)) and Weimarck (Svensk Bot. Tid. 40: 143 (1946)) found that, on average, tropical and South African specimens of Juncus effusus possess slightly smaller flowers than is usually found in European material, and have more lax and more slender inflorescences. This African form was described as Juncus laxus by Robyns & Tournay. Although the average size of the flowers is smaller, African material I have examined also revealed that a good proportion of plants have flowers as large as those in European material, This, together with the fact that a similar proportion of European specimens examined were found to possess the smaller sized flowers, indicates that flower-size is not significant when considering them as belonging to two different taxa. Furthermore, the laxity and slenderness of the inflorescences hold no significance as distinguishing characters for African material, the occurrence of plants with these features, and of those with more dense and robust inflorescences being the same as for European material. I have concluded therefore that J. laxus is synonymous with J. effusus.

True's Beaked Whale from the South-East Coast of South Africa

Mesoplodon mirus True, True's beaked whale, is known from fourteen stranded specimens from the shores of the North Atlantic, the most northerly specimen being from the Outer Hebrides and the most southerly from Florida1. On May 21, 1959, a 17 ft. 6 in. beaked whale was washed up at Wilderness, 170 miles eastwards along the coast from Cape Agulhas, the southernmost tip of Africa. The skeleton of this whale was saved from the axes of the health authority's disposal squad by Mr. B. L. Cairncross, a local naturalist, and presented to the South African Museum. This whale proves to be an adult male True's whale. Dr. F. C. Fraser has kindly compared photographs of this specimen with the example of True's whale in the British Museum (Natural History), and confirms this identification, stating, however, that the lower jaw of the South African specimen appears deeper and more massive than the British Museum example.