The status and importance of cephalopod systematics in southern Africa

A checklist of southern African cephalopods published in 1974 listed 94 species for the region 20–45°S, 10–40°E. Just 23 years later the number of known species has doubled to an estimated 195, represented in theSouth African Museum collection by 4 252 accessioned lots (15 434 specimens, excluding many paralarvae). In 1995, cephalopods constituted the sixth most valuable fisheries resource worldwide (after shrimps and tunas). Only one subspecies, Loligo vulgaris reynaudii, is targeted in South Africa at present, but it is important commercially because of the high prices it commands internationally. A number of other species constitute alternate resources of potential commercial interest, including at least 12 sepiids, 7 loliginids, 6 ommastrephids and 9 octopods. Cephalopods are also important in the trophic relations of marine fish, birds and mammals. Knowledge of the southern African cephalopod fauna is important not only for regional biodiversity studies but also from a wider perspective. The region is strategically placed between the Atlantic, Indian and Southern oceans and the faunal composition is complex. The southern African cephalopods include about 20–30% of the known world cephalopod species. Resolution of taxonomic problems in the southern African context goes a long way towards global resolution, particularly among the oceanic species. The size and complexity of the South African Museum’scephalopod collection prompted the holding of a systematics workshop to produce a guide to southern African cephalopods. This paper provided a basis for that Biodiversity Workshop. A provisional checklist for the region is provided, species constituting a potential resource for either artisanal or larger fisheries are identified and unresolved problems in the systematics (including an undescribed genus and at least 12, but probably more than 20, new species) are indicated

Cephalopods in the diet of sperm whales caught commercially off Durban, South Africa

A collection from stomach contents of 30 sperm whales Physeter catodon comprised a total of 46 cephalopods belonging to six families. Nine species were identified, including Ommastrephes bartramii, which is recorded for the first time in the diet of sperm whales caught off South Africa, and Todarodes filippovae, which has only previously been identified from whale stomachs to genus. Sexed individuals of all species were female and most were gravid. Comparisons are made with a much larger collection of beaks from the same source and the species identity of some of these can now be established or confirmed

The Capital gains tax - Implications of holding limited interests in property

For the purposes of capital gains tax (CGT) an 'asset' includes 'property of whatever nature, whether movable or immovable, corporeal or incorporeal...' and 'a right or interest of whatever nature to or in such property'.1 It is clear from this definition that an 'asset' includes limited interests in property that are real rights such as bare dominium, a usufruct, a fiduciary interest, a right of usus, a right of habitatio and grazing rights, as well as personal rights such as the right to income from a trust and the right to occupy trust property. In this article an attempt is made to clarify the position regarding the impact of CGT on the disposal of these limited interests

Computational Evaluation of Me₂TCCP as Lewis acid

Supramolecular adducts between dimethyl‐2,2,3,3‐tetracyanocyclopropane (Me(2)TCCP) with 21 small (polar) molecules and 10 anions were computed with DFT (B3LYP‐D3/def2‐TZVP). Their optimized geometries were used to obtain interaction energies, and perform energy decomposition and ‘atoms‐in‐molecules’ analyses. A set of 38 other adducts were also evaluated for comparison purposes. Selected examples were further scrutinized by inspection of the molecular electrostatic potential maps, Noncovalent Interaction index plots, the Laplacian, the orbital interactions, and by estimating the Gibbs free energy of complexation in hexane solution. These calculations divulge the thermodynamic feasibility of Me(2)TCCP adducts and show that complexation is typically driven by dispersion with less polarized partners, but by orbital interactions when more polarized or anionic guests are deployed. Most Me(2)TCCP adducts are more stable than simple hydrogen bonding with water, but less stable than traditional Lewis adducts involving Me(3)B, or a strong halogen bond such as with Br(2). Several bonding analyses showed that the locus of interaction is found near the electron poor sp(3)‐hydridized (NC)(2)C−C(CN)(2) carbon atoms. An empty hybrid σ*/π* orbital on Me(2)TCCP was identified that can be held responsible for the stability of the most stable adducts due to donor‐acceptor interactions

First study on the ecology of Sepia australis in the Southern Benguela Ecosystem

Sepia australis is most abundant in the eastern South Atlantic between Luderitz and St. Helena Bay (about 27-35°S in 100-200m). There seems to be no link between the variation in abundance of S. australis and that of its most important predator, the shallow-water Cape hake, Merluccius capensis. The variations in abundance of S. australis and one of its most important prey species, the stomatopod crustacean Pterygosquilla armata capensis, show simultaneous changes, suggesting that both species respond to the same environmental factors. Mantle length, total weight, gonad weight, and sex ratio of Sepia australis vary from year to year and by region off the west coast of southern Africa. Animals from the south coast (eastward of Cape Point) were very different: length-weight relationhips were found to be similar in slope and intercept for both sexes and within each sex between years and regions off the west coast, but different for the south coast