The Mollusc collections at South African institutions: Development and current status

There are three major mollusc collections in South Africa and seven smaller, thematic collections. The KwaZulu-Natal Museum holds one of the largest collections in the southern hemisphere. Its strengths are marine molluscs of southern Africa and the southwestern Indian Ocean, and terrestrial molluscs of South Africa. Research on marine molluscs has led to revisionary papers across a wide range of gastropod families. The Iziko South African Museum contains the most comprehensive collections of Cephalopoda (octopus, squid and relatives) and Polyplacophora (chitons) for southern Africa. The East London Museum is a provincial museum of the Eastern Cape. Recent research focuses on terrestrial molluscs and the collection is growing to address the gap in knowledge of this element of biodiversity. Mollusc collections in South Africa date to about 1900 and are an invaluable resource of morphological and genetic diversity, with associated spatial and temporal data. The South African National Biodiversity Institute is encouraging discovery and documentation to address gaps in knowledge, particularly of invertebrates. Museums are supported with grants for surveys, systematic studies and data mobilisation. The Department of Science and Innovation is investing in collections as irreplaceable research infrastructure through the Natural Science Collections Facility, whereby 16 institutions, including those holding mollusc collections, are assisted to achieve common targets and coordinated outputs.

Malacofaunal inventory in Chintamoni Kar Bird Sanctuary, West Bengal, India

The knowledge on the floral and faunal composition of protected areas (PAs) is crucial for formulating suitable conservation plan. In this paper, inventory and species richness of non-marine molluscs of Chintamoni Kar Bird Sanctuary has been made and is for the first time from any PA of West Bengal. A total of 276 specimens belonging to 22 species (10 species of land snails and 12 species of freshwater) of non-marine molluscs (land and freshwater) were collected and examined from this sanctuary. The malacofaunal inventory comprises of nine genera under seven families among land snails and 12 genera & seven families from both gastropods & bivalves under the freshwater forms. As far as species richness is concerned, the family Ariophantidae was found to be dominant among land forms whereas species of the families Thiaridae and Unionidae were dominant among freshwater forms.

Stratigraphy, chronology and palaeontology of the Tertiary rocks of the Cheringoma Plateau, Mozambique

The discovery of fossil plants, marine molluscs and mammals in the Mazamba Formation, Cheringoma Plateau, Mozambique, opens a new chapter in the study of this part of the African Rift System. The evidence suggests that the Mazamba Formation is older than previously reported, probably late Eocene rather than Miocene. The fossil wood and stems indicate a frost-free tropical humid environment and a high water table soon after deposition, and the marine molluscs and mammals indicate proximity to the sea. There is also evidence for the occurrence of pans in the area during the late Eocene which also suggest a near-surface water table. This paper discusses the history of interpretation of the geology of the Cheringoma Plateau and describes and interprets the fossil plants, molluscs and mammals collected in 2012 and 2013. It is concluded that the Mazamba Formation, which overlies the fully marine Lutetian-Bartonian Cheringoma Limestone, is a coastal facies (fluvio-deltaic, lagoonal and onshore deposits) that accumulated on top of the marine limestones as sea level dropped late in the Bartonian. Mammalian bones from the White Patch sites represent a heavily built species about the dimensions of a pygmy hippopotamus, probably belonging to the order Embrithopoda. If so, then the Mazamba Formation is likely to correlate to the latest Bartonian or early Priabonian rather than to the Miocene as previously assumed.

Transcriptional regulation mechanism of sterol regulatory element binding proteins on Δ6 fatty acyl desaturase in razor clam Sinonovacula constricta

The razor clam, Sinonovacula constricta, contains high levels of long-chain PUFA (LC-PUFA), which are critical for human health. In addition, S. constricta is the first marine mollusc demonstrated to possess Δ6 fatty acyl desaturase (Fad) and complete LC-PUFA biosynthetic ability, providing a good representative to investigate the molecular mechanism of sterol regulatory element binding proteins (SREBP) in regulating Δ6 Fad for LC-PUFA biosynthesis in marine molluscs. Herein, S. constricta SREBP and Δ6 Fad promoter were cloned and characterised. Subsequently, dual luciferase and electrophoretic mobility shift assays were conducted to explore the SREBP binding elements in the core regulatory region of S. constricta Δ6 Fad promoter. Results showed that S. constricta SREBP had a very conservative basic helix-loop-helix-leucine zipper motif, while S. constricta Δ6 Fad promoter exhibited very poor identity with teleost Fads2 promoters, indicating their differentiation during evolution. A 454 bp region harbouring a core sequence in S. constricta Δ6 Fad promoter was predicted to be essential for the transcriptional activation by SREBP. This was the first report on the regulatory mechanism of LC-PUFA biosynthesis in marine molluscs, which would facilitate optimising the LC-PUFA biosynthetic pathway of bivalves in further studies.