Upeneus floros, a new goatfish from South Africa and Mozambique, with updated taxonomic accounts for U. guttatus and U. pori and a key to Western Indian Ocean Upeneus species (Mullidae)

The highly diverse goatfish genus Upeneus (Mullidae) requires enhanced attention regarding the possible occurrence of undescribed species in insufficiently explored regions. This study focuses on the South-Western Indian Ocean region (SWIO), and on the so-called japonicus-group, a taxonomic species group of Upeneus. Based on in-situ observations and collections in Sodwana Bay, KwaZulu-Natal, South Africa, the Floros goatfish, U. floros n. sp., is described. Detailed comparative studies of colour patterns and morphological characters of all other 13 japonicus-group species were undertaken as well as COI barcoding. The new species occurs in the coastal area between Angoche, N Mozambique and KwaZulu-Natal and partly overlaps in distribution with two similar species, U. guttatus, widely distributed in the Indo-W Pacific, and U. saiab, assumed to be endemic in a small area off Angoche. Two additional japonicus-group species occurring in the SWIO, U. seychellensis from the Seychelles Bank and U. pori from the Mediterranean Sea (as Lessepsian migrant), Northern Red Sea and Madagascar, were also compared. Because specimens as well as in-situ photographs of U. floros have been erroneously identified as either U. guttatus or U. pori during previous studies, updated taxonomic accounts and diagnoses are provided for these species taking size-related and population differences into account. For U. pori, of which a single preserved specimen from SW Madagascar was known so far, a new record from NE Madagascar is reported based on three specimens and a fresh-colour photo. Upeneus floros can be distinguished from U. guttatus and U. pori by a combination of three characters: head length, first dorsal-fin height and number of gill rakers. Upeneus guttatus can be distinguished from the other two species by disproportionally higher anterior dorsal-fin spines vs. a proportional decrease of dorsal-fin spines in height, barbels mostly yellow vs. white or creamy-white, and slightly fewer pectoral-fin rays. COI barcoding detected a clear distinction between U. guttatus and U. floros and U. pori, respectively, but no significant divergence between the two latter species. COI barcoding also failed to differentiate several other Upeneus species which are clearly distinguished morphologically. Possible interrelationships between species distribution patterns and physical oceanography are discussed. An identification key for the 22 WIO Upeneus species is provided.publishedVersio

Upeneus floros, a new goatfish from South Africa and Mozambique, with updated taxonomic accounts for U. guttatus and U. pori and a key to Western Indian Ocean Upeneus species (Mullidae)

The highly diverse goatfish genus Upeneus (Mullidae) requires enhanced attention regarding the possible occurrence of undescribed species in insufficiently explored regions. This study focuses on the South-Western Indian Ocean region (SWIO), and on the so-called japonicus-group, a taxonomic species group of Upeneus. Based on in-situ observations and collections in Sodwana Bay, KwaZulu-Natal, South Africa, the Floros goatfish, U. floros n. sp., is described. Detailed comparative studies of colour patterns and morphological characters of all other 13 japonicus-group species were undertaken as well as COI barcoding. The new species occurs in the coastal area between Angoche, N Mozambique and KwaZulu-Natal and partly overlaps in distribution with two similar species, U. guttatus, widely distributed in the Indo-W Pacific, and U. saiab, assumed to be endemic in a small area off Angoche. Two additional japonicus-group species occurring in the SWIO, U. seychellensis from the Seychelles Bank and U. pori from the Mediterranean Sea (as Lessepsian migrant), Northern Red Sea and Madagascar, were also compared. Because specimens as well as in-situ photographs of U. floros have been erroneously identified as either U. guttatus or U. pori during previous studies, updated taxonomic accounts and diagnoses are provided for these species taking size-related and population differences into account. For U. pori, of which a single preserved specimen from SW Madagascar was known so far, a new record from NE Madagascar is reported based on three specimens and a fresh-colour photo. Upeneus floros can be distinguished from U. guttatus and U. pori by a combination of three characters: head length, first dorsal-fin height and number of gill rakers. Upeneus guttatus can be distinguished from the other two species by disproportionally higher anterior dorsal-fin spines vs. a proportional decrease of dorsal-fin spines in height, barbels mostly yellow vs. white or creamy-white, and slightly fewer pectoral-fin rays. COI barcoding detected a clear distinction between U. guttatus and U. floros and U. pori, respectively, but no significant divergence between the two latter species. COI barcoding also failed to differentiate several other Upeneus species which are clearly distinguished morphologically. Possible interrelationships between species distribution patterns and physical oceanography are discussed. An identification key for the 22 WIO Upeneus species is provided

Impact of offshore eddies on shelf circulation and river plumes of the Sofala Bank, Mozambique Channel

A high-resolution, two-way nested Regional Ocean Modeling System, forced with monthly climatologies, has been set up for the Sofala Bank and adjacent deeper ocean of the Mozambique Channel to investigate the role of offshore mesoscale eddies on the shelf circulation, hydrographic structures and river plumes. The model is shown in comparison with available observations and published studies. Most known oceanographic features are reproduced by our model. We applied Self-Organizing Maps and showed that offshore passing eddies, depending on their strength and proximity to the shelf, modulate the shelf circulation and river plume direction and spread. The presence of a strong cyclonic eddy close to the shelf induces northward surface shelf currents. In contrast, the presence of a strong anticyclonic eddy close to the shelf induces a strong southward current over most of the shelf, except off Beira. Our analyses confirm that the plume of the Zambezi River is bi-directional. The southward-directed plume patterns, opposite to the dominant northwards, occur in response to nearby offshore anticyclonic eddies (26% of occurrence). This behavior could have an influence on water dispersal, shelf ecosystems and important fisheries. Therefore, offshore mesoscale eddies should be taken into account when studying the ocean dynamics of the Sofala Bank

Spawning areas of two shallow-water penaeid shrimps (penaeus indicus and metapenaeus monoceros) on the sofala bank, mozambique

Penaeus indicus and Metapenaeus monoceros are commercially important penaeid shrimp species in the Western Indian Ocean, supporting fisheries on the Sofala Bank, Mozambique. Despite their importance, critical gaps exist in knowledge that is relevant for management purposes. In particular, there is poor understanding of the spatial patterns in spawning for the two species. To fill this gap, we used annual data of mature female stages from research surveys conducted in late summer during January/February from 2003 to 2017. Three distinct spawning areas for P. indicus and M. monoceros were identified (northern, central and southern), all adjacent to river mouths. Spawning areas of the two species overlapped in waters shallower than 25 m, but M. monoceros spawning areas also extended to deeper (45 m) waters. Spawning areas of the two species had different spatial extents, with M. monoceros extending to the north and P. indicus to the south. The northern and central spawning areas were more persistent than the southern area. The central spawning area, however, has shifted northward for the two species during the recent period of depleted stock since 2012. We also used daily industrial catch rate data from the fishing season in March–November 2004 to 2017 to investigate annual patterns. High abundance indices of the two species were observed in the northern and central areas of the Licungo River. Catch rates, however, suggest seasonal variability with depth for the two species. This study provides new information on species-specific spawning patterns in space, which should be considered in future management approaches and spatial planning