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Freshwater ecosystems are the most threatened on Earth, with many species facing extinction. The Clanwilliam sandfish (Labeo seeberi) is South Africa's most threatened migratory freshwater fish and is endemic to the Olifants–Doring River system in the Cape Fold Ecoregion. Non‐native fish predation and river desiccation have caused a recruitment bottleneck, severely compromising juvenile survival and resulting in a declining population of aging sandfish. The Saving Sandfish Project launched an emergency head‐start intervention in 2020 to reduce extinction risk. We (1) rescued juvenile sandfish from drying pools in a key spawning tributary (the Biedouw River); (2) relocated them to 6 off‐stream reservoirs; and (3) released reservoir‐reared sandfish back into their natal river once large enough to evade non‐native fish predation. Here, we estimate survival in the reservoir environment, evaluate return rates relative to wild run size, and assess the probability of return based on conditions at release. Between 2020 and 2022, we stocked 33,391 juvenile sandfish into the 6 reservoirs. After 1 year, the estimated survival rate at one reservoir was 0.679 (range based on 95% CI: 0.385–0.973). Release and return results are presented only for the first (2020) rescue cohort. In 2021, we released 1277 sandfish from 2 reservoirs into the Biedouw River, comprising 16.6% of the 2020 rescue cohort. Mean size at release was 169 mm (SE 0.6) total length. Of those released, 994 were PIT‐tagged. A total of 77 PIT‐tagged sandfish were recorded during the 2022 spawning migration—a return rate of 7.7% of tagged releases in the first year of returns. Size of fish and distance from the Doring River at release were significant predictors of return probability, with larger fish released further from the Doring experiencing a higher probability of return. This program serves as a model for the conservation of freshwater fish where there is an imminent and high risk of extinction. [ABSTRACT FROM AUTHOR]

Recent phylogeographic studies of poorly-dispersing coastal invertebrates in highly biodiverse regions have led to the discovery of high levels of cryptic diversity and complex phylogeographic patterns that suggest isolation, geological, and ecological processes have shaped their biodiversity. Studies of southern African coastal invertebrates have uncovered cryptic diversity for various taxa and phylogeographic patterns that, although sharing some similarities across taxa, do differ. These findings underscore the need for additional studies to better understand the biodiversity levels, distributional patterns, and processes responsible for producing coastal biodiversity in that region. The coastal isopod Deto echinata is of particular interest, as its complex taxonomic history, poor dispersal capabilities, and broad geographic distribution suggest the potential for cryptic diversity. We use mitochondrial and nuclear sequences to characterize D. echinata individuals from localities ranging from northern Namibia to Glentana, about 2,500 km along the coastline on the south coast of South Africa. These are used to assess whether D. echinata harbors cryptic genetic diversity and whether phylogeographic distributional patterns correlate with those previously documented for other coastal isopods in the region. Analysis of mitochondrial and nuclear sequences revealed two deeply-divergent lineages that exhibit a distributional break in the Cape Peninsula region. These findings suggest D. echinata is a cryptic species complex in need of taxonomic revision and highlight the need for further taxonomic and phylogeographic studies of similarly poorly-dispersing coastal invertebrates in southern Africa. [ABSTRACT FROM AUTHOR]

In South Africa, freshwater habitats are among the most threatened ecosystems, and freshwater fishes are the most threatened species group. Understanding patterns in freshwater fish diversity, threat, invasion, and protection status are vital for their management. However, few studies have undertaken such analyses at ecologically and politically appropriate spatial scales, largely because of limited access to comprehensive biodiversity data sets. Access to freshwater fish data for South Africa has recently improved through the advent of the Freshwater Biodiversity Information System (FBIS). We used occurrence records downloaded from the FBIS to evaluate spatial patterns in distribution, diversity, threat, invasion, and protection status of freshwater fishes in South Africa. Results show that record density varies spatially, at both primary catchment and provincial scales. The diversity of freshwater fishes also varied spatially: native species hotspots were identified at a provincial level in the Limpopo, Mpumalanga, and KwaZulu-Natal provinces; endemic species hotspots were identified in the Western Cape; and threatened species hotspots in the Western Cape, Mpumalanga, Eastern Cape, and KwaZulu-Natal. Non-native species distributions mirrored threatened species hotspots in the Western Cape, Mpumalanga, Eastern Cape, and KwaZulu-Natal. Some 47% of threatened species records fell outside of protected areas, and 38% of non-native species records fell within protected areas. Concerningly, 58% of the distribution ranges of threatened species were invaded by non-native species. [ABSTRACT FROM AUTHOR]

Octopus vulgaris type III preys upon molluscs by drilling a hole in the shell, through which it injects venom, weakening the muscles and allowing the octopus to remove and eat the mollusc flesh. In False Bay, South Africa, the abalone Haliotis midae, the kelp limpet Cymbula compressa and the helmet snail Semicassis zeylanica, are all common octopus prey, but each has a very different shell morphology and underlying anatomy. It is hypothesized that O. vulgaris type III targets the muscle attachment site of all three species and that the precision of drilling should correlate with the relative size of these muscle attachment sites. Measurements of the locations of drill holes from collected shells of each species showed that drilling locations were significantly non-random. In the abalone and limpet, the muscle attachment site was targeted two and 4.5 times more frequently than expected, respectively. Octopus vulgaris type III drilled helmet snails with extreme precision, with over half the holes drilled on the spire at an angle of 45° and 90° from the lip. Kernel density heat maps demonstrated that octopus drilled abalone with low precision, limpets with medium precision and helmet snails with high precision. The reason for the high precision in the helmet snail remains speculative, as the main drilling location did not align with the columellar muscle attachment and no target could be defined. This study is the first to assess octopus drilling in temperate southern Africa and to compare drilling precision across different prey species. [ABSTRACT FROM AUTHOR]

Freshwater fishes are recognised as South Africa's most threatened species group. Reliable, long-term data on fish occurrence records are critical for effectively managing and conserving these species. A comprehensive freshwater fish dataset was compiled and uploaded to the Freshwater Biodiversity Information System (FBIS, freshwaterbiodiversity.org), comprising all available records of formally described freshwater fish species occurring in South Africa. An 18-month historic-data collation effort resulted in the accrual of 35 955 new records of freshwater fish from South Africa spanning 194 years (1828-2022), that have since been uploaded to the Global Biodiversity Information Facility (GBIF). Together with pre-existing GBIF records (24 861), a total of 60 837 freshwater fish records are thus now available for South Africa. The data show a marked decline in the number of native fish occurrence records over the last decade. Conversely, the number of occurrences for non-native fishes increased over the past three decades. A data breakdown is provided for each of South Africa's nine provinces including total number of records, and the numbers of native, non-native, endemic and threatened species. These data provide a much-needed update of the known status and distribution of freshwater fishes in the country. [ABSTRACT FROM AUTHOR]

The tanaid Pagurapseudes dentatus was described from a male collected from the intertidal zone at False Bay, South Africa. The description was poorly illustrated, incomplete, did not describe the female or juvenile stages, and gave no information on its habitat. The species was rediscovered and found to be locally abundant at locations in South Africa, where it inhabits vacant gastropod shells. We redescribe P. dentatus by fully illustrating and describing its morphological characters, including the copulatory female and manca II stages. Pagurapseudes dentatus differs from similar species by a long seta on the basis of the characteristically elongated pereopod-1, as well as its singular distal pectinate setae on the propodus and adjacent to the dactylus of pereopod 6. Nano-CT scanning was used to illustrate and document the unusual mode of occupation of empty gastropod shells by the species. It was found (N = 139) occupying shells of 19 gastropod species from 10 different genera, occurring most abundantly in shells of Tricolia Risso, 1826, Burnupena Iredale, 1918, Assiminea Fleming, 1828, and Gibbula Risso, 1826. It forms dense populations under intertidal boulders, where it co-occurs with, and may compete for empty shells, with at least two common species of hermit crabs. [ABSTRACT FROM AUTHOR]

The parapagurid hermit crabs Sympagurus dimorphus (Studer, 1883) and Parapagurus bouvieri (Stebbing, 1910) form dominant components of South African deeper‐water benthic invertebrate communities and, as adults, forego the use of "traditional" gastropod shells in favour of symbiotically associated Epizoanthus carcinoecia. A total of 1,122 adult S. dimorphus and 549 adult P. bouvieri derived from demersal research trawl surveys were examined to investigate parameters of population structure, carcinoecia association and morphology. S. dimorphus had a female‐biased sex ratio of 1:1.5, and P. bouvieri an equal sex ratio of 1:1. The proportion of males of both species increased with cephalothoracic shield length (CL). The lengths of the major right chelipeds of both S. dimorphus males and females, and P. bouvieri males were positively allometric, and negatively allometric in P. bouvieri females. All P. bouvieri inhabited carcinoecia, while 3.39% (n = 38) of S. dimorphus specimens occupied gastropod shells. There was a positive relationship between S. dimorphus CL and rate of gastropod shell occupation (r2 = 0.96). In S. dimorphus, number of zoanthid polyps forming the carcinoecia pseudoshell increased with both total shell volume (R2 = 0.73) and colony height (R2 = 0.61), but no such relationships were found for P. bouvieri. Euspira napus was the most common original shell around which carcinoecia developed in both S. dimorphus (45.45%) and P. bouvieri (39.00%). We speculate that these hermit species exist along an evolutionary continuum of carcinoecia use. Sympagurus dimorphus retains the ability to occupy both gastropod shells and pseudoshells and, like most other hermit crabs, continue to use shells/carcinoecia as shelters to protect the entire body. In contrast, adult P. bouvieri appear to be totally reliant on carcinoecia, which they use more as a brood pouch covering only the abdomen, rather than as a shelter into which they can fully retract to escape predation. [ABSTRACT FROM AUTHOR]

To date, living acrothoracican barnacles have only been directly observed burrowing into the skeletons of marine animals or into calcareous rocks. While surveying the Acrothoracica of South Africa, we recorded live Weltneria spinosa Berndt, 1907, burrowed into a beach-cast rhodolith, comprising non-geniculate coralline red algae from the genus Lithophyllum Philippi, 1837. Unoccupied holes of the same acrothoracican were also found in another rhodolith identified as Neogoniolithon brassica-florida (Harvey) Setchell & L.R.Mason, 1943. A search of herbarium material also revealed the same acrothoracican species burrowing into two thick discoid coralline algal species, Lithophyllum neoatalayense Masaki, 1968, and Heydrichia woelkerlingii R.A.Townsend, Y.M.Chamberlain & Keats, 1994. These are the first unequivocal records of living acrothoracicans burrowing into coralline red algae. The fact that several algal species were colonized and that these were found across a range of sites suggests that coralline algae represent a previously unknown habitat type for this group of barnacles and that this habitat greatly increases the known range of substrates available for colonization. Further inspections of coralline algae in this and other regions will likely reveal many more new host records and possibly new host-specific acrothoracican species. [ABSTRACT FROM AUTHOR]

The herbivorous amphipod Sunamphitoe roberta n. sp. is described from the canopy of kelp beds in False Bay, South Africa. The new species has unusual habits, small family groups burrowing directly into the margins of the swollen primary fronds of the kelp Ecklonia maxima (Osbeck) Papenfuss, 1940. Morphologically, the new species is best distinguished from other species of Sunamphitoe by strong rows of dorsal spines on the outer rami of uropods 1 and 2. These spine rows appear to be employed as 'drill-bits' to excavate kelp tissue and create the burrows. Damage to hosts does not appear to be fatal, but requires further investigation. [ABSTRACT FROM AUTHOR]

The first records of the maritime earwig Anisolabis maritima from South Africa are reported. The species was first discovered in 2015 in the upper intertidal zone of an artificial rubble causeway at Port Shepstone, on the east coast of South Africa, where it appears to feed on driftline isopods and amphipods. The study site operated briefly as a harbour from 1880-1902, suggesting that this introduction took place via shipping at that time and has remained undetected for more than a century. [ABSTRACT FROM AUTHOR]

A new species of hermit crab, Pagurus fraserorum n. sp. (family Paguridae) is described from rocky subtidal reefs off KwaZulu-Natal, South Africa, and illustrated using both conventional drawings and colour photographs, and via three-dimensional (3D) X-ray micro-computed tomography (μCT). Because of the limitation μCT has in detecting very fine and soft structures, a novel approach of manually drawing setation and spinulation onto the two-dimensional images of the 3D visualizations was used to illustrate the pereopods. In addition, an interactive figure and rotation movie clips in the supplement section complement the species description, and the 3D raw data of the 3D type data are downloadable from the Gigascience Database repository. The new species is the sixth species of Pagurus Fabricius, 1775 reported from South Africa and is closely allied to the Indo-Pacific P. boriaustraliensis Morgen, 1990 and P. pitagsaleei McLaughlin, 2002, from which it differs by its shorter ocular peduncles, by the armature of the carpus of the right cheliped, and also in colouration. This study presents the first description of a hermit crab in which a majority of taxonomic details are illustrated through 3D volume-rendered illustrations. In addition, colour photographs and COI molecular barcodes are provided, and the latter compared to COI sequences of specimens from Western Australia previously identified as P. boriaustraliensis and of specimens of P. pitagsaleei from Taiwan, as well as to three additional South African members of the genus. The South African taxon was confirmed to be genetically distinct from all species tested. [ABSTRACT FROM AUTHOR]

The porcelain crab Porcellana africana Chace, 1956, a species native to NW Africa, between Western Sahara and Senegal, is reported from Saldanha Bay, South Africa, and both morphological evidence and DNA analysis are used to confirm its identity. The taxonomic history of P. africana is summarized, and the taxonomic implications of the DNA analysis are discussed. The observations that the South African population appeared suddenly and that it is located in and around a major international harbour, strongly suggest that it represents a recent shipping introduction. Porcellana africana was first detected at a single site within Saldanha Bay in 2012, but by 2016 was abundant under intertidal boulders and within beds of the invasive mussel Mytilus galloprovincialis across most of the Bay. It remains absent along the adjacent oceanic coastline and in other regional harbours, but these should be monitored to detect any subsequent range expansion. [ABSTRACT FROM AUTHOR]

Recent phylogeographic studies along the coastline of southern Africa have uncovered cryptic diversity in several coastal invertebrates, including direct developing crustaceans in the superorder Peracarida. These findings indicating the possible existence of additional cryptic diversity in other yet to be studied peracarids, particularly those known to harbor said cryptic diversity in other regions of the world. Isopods in the genus Ligia are one such taxon. They inhabit patchy rocky beaches, are direct developers, avoid the open water, and exhibit other biological traits that severely constrain their dispersal potential (e.g., poor desiccation resistance). These traits are thought to have led to long- term isolation of populations, and allopatric diversification in Ligia species around the world; however, Ligia species in southern Africa, where three endemic Ligia species of uncertain validity are known to exist, remain unstudied to date. In this study, we used mitochondrial and nuclear markers to characterize Ligia collected in 18 localities from Namibia to the KwaZulu-Natal region of South Africa. We report the presence of cryptic lineages within Ligia species in the region that suggest the need for taxonomic reevaluation of these isopod species. [ABSTRACT FROM AUTHOR]

Background: Along with the conventional deposition of physical types at natural history museums, the deposition of 3-dimensional (3D) image data has been proposed for rare and valuable museum specimens, such as irreplaceable type material. Findings: Micro computed tomography (µCT) scan data of 5 hermit crab species from South Africa, including rare specimens and type material, depicted main identification characteristics of calcified body parts. However, low-image contrasts, especially in larger (>50 mm total length) specimens, did not allow sufficient 3D reconstructions of weakly calcified and fine characteristics, such as soft tissue of the pleon, mouthparts, gills, and setation. Reconstructions of soft tissue were sometimes possible, depending on individual sample and scanning characteristics. The raw data of seven scans are publicly available for download from the GigaDB repository. Conclusions: Calcified body parts visualized from µCT data can aid taxonomic validation and provide additional, virtual deposition of rare specimens. The use of a nondestructive, nonstaining µCT approach for taxonomy, reconstructions of soft tissue structures, microscopic spines, and setae depend on species characteristics. Constrained to these limitations, the presented dataset can be used for future morphological studies. However, our virtual specimens will be most valuable to taxonomists who can download a digital avatar for 3D examination. Simultaneously, in the event of physical damage to or loss of the original physical specimen, this dataset serves as a vital insurance policy. [ABSTRACT FROM AUTHOR]

Surveys of species diversity in sublittoral waters along the coasts of the Cape Peninsula on the Atlantic coast of South Africa yielded three species of Mysidopsis G.O. Sars, 1864. A new species, M. abbreviata   n. sp. is described, a supplementary description is given for M. similis (Zimmer, 1912), and the female of M. zsilaveczi   Wittmann & Griffiths, 2014 is described for the first time. The new species is characterized, among other characters, by a transversely shortened rostrum. Field observations of M. zsilaveczi and M. abbreviata   n. sp. showed the greatest intraspecific diversity of colour patterns ever documented for mysids. Stomach contents, together with differences in the armature of perioral mouthparts and in the foregut, suggest that all three species are specialized predators, mainly of crustaceans. An updated key to the species of Mysidopsis in southern Africa is given. [ABSTRACT FROM AUTHOR]

A long-term sightings and photographic identification (photo-ID) database documented the inter-annual and monthly trends in white shark ( Carcharodon carcharias) sightings, sex ratios and life-history stages at Seal Island, False Bay, South Africa, over the period 2004-2012. A total of 1105 sightings were recorded during 171 scientific surveys incorporating 577 h of observation (annual mean 64.10 h, range 23.71-178.69 h). The mean annual sighting rate was 1.87 (range 0.90-3.19) sharks per hour and sighting rates declined over the nine-year study period. It is unknown whether the decline resulted from an actual population decline, or was due to changes in shark distribution or environmental conditions, but it highlights the need for ongoing monitoring at this site. The overall sex ratio was 1.0: 1.0: 2.3 for male: female: unsexed sharks, respectively. Of the 1105 sightings, 39% ( n = 433) were photo-ID'd, representing 303 individual sharks (112: 111: 80, male: female: unsexed) and 130 resightings. Of the 303 photo-ID'd sharks, 71% were sighted in a single year only, indicative of transient behaviour. Of the 29% of sharks that were resighted in more than one year, 65% were resighted in the following year, indicating site fidelity to Seal Island, whereas 35% skipped one or more years between encounters, indicative of a temporary absence. The majority (60%) of the photo-ID'd sharks were immature, 32% were subadult and only 8% were mature. No young-of-the-year sharks and few adults were recorded, indicating that Seal Island is not an adult aggregation site, nor a pupping or nursery area, but rather is best described as a seasonal feeding ground. Large females were rarely resighted again after they approached length-at-maturity (≥450 cm TL), whereas some adult males were recorded consistently across years. The emigration of subadult female sharks approaching maturity from Seal Island, combined with the small number of mature sharks of both sexes reported from any South African location, indicate that adult aggregation sites, and thus areas of reproductive importance, still remain unknown. [ABSTRACT FROM AUTHOR]

Faunistic studies in sublittoral and littoral marine habitats on the Cape Peninsula, South Africa, have yielded three new species belonging to the genus Heteromysis, subgenus Heteromysis: H. cancelli sp. n. associated with the diogenid hermit crab Cancellus macrothrix Stebbing, 1924, and H. fosteri sp. n. extracted from 'empty' urchin and gastropod shells. The first documented mysid-cephalopod association is reported for H. octopodis sp. n. which was found in dens occupied by Octopus vulgaris Cuvier, 1797, but was also captured from tide pools. The three new species differ from previously known E. Atlantic species, among other characters, by a single spine on the endopods of uropods in combination with large cornea and absence of median sternal processes on thoracic somites. They are also characterized by a white stripe along the dorso-lateral terminal margin of the eyestalks in living specimens. The new species appear quite similar to each other, but are distinguished by different depths of the telson cleft, different distributions of spines on the lateral margins of the telson, different numbers of segments on thoracic endopod 4, and by differently modified setae on the carpus of the third thoracic endopod, as well as on the carpopropodus of the fourth endopod. An updated key to the species of Heteromysis known from the E. Atlantic is given. [ABSTRACT FROM AUTHOR]

This article describes the reproductive biology and developing young of Amphiura capensis, a small brooding brittle star found in the intertidal zones of Namibia and South Africa. Each month from October 2014 to September 2015, 20 specimens were collected from Mouille Point, Cape Town, South Africa, and dissected for internal examination of brooding characteristics. Disc diameters of 238 analyzed adults ranged 2.5-8.7 mm, with a mean of 6.15 mm (SD = 1.10 mm). Brooding was exhibited in 60.5% of all sampled individuals, of which 30.6% contained young of only one of six subjectively chosen size classes, 31.9% contained two size classes, and the rest (37.5%) contained more than two size classes at the same time. Young within the same bursa were commonly of the same size class, which suggests sequential brooding. However, multiple size classes of young were often present within different bursae of the same parent, which thus exhibited characteristics of both sequential and simultaneous brooding. Of 584 brooded young retrieved from dissections, an average of 2.5 (SD = 3.2) and a maximum of 14 young were recorded within a single parent. As no larval stages were observed, development was assumed to be direct. Threedimensional visualizations of μCT scans revealed the positions of the brooded young to be quite different from those in other species, facing with their mouths downwards instead of upwards, and not all pressed against the adult's bursal wall. Brooding occurred throughout the year, but numbers of young peaked in austral winter, coinciding with warmer water temperatures at this site. The duration of brooded development was estimated to be ~6 months, comparable with other species with similar reproductive biology. [ABSTRACT FROM AUTHOR]

Two introduced beachfleas,Orchestia gammarellusandPlatorchestia platensis, have been recorded from South Africa, but have been misidentified by some earlier researchers and, prior to this study, each was also known from just a few, scattered observations, such that their true distributions remained obscure. We illustrate both species to clarify the features that identify and distinguish them and determine their true distributions by re-examining historical samples and by collecting new material from estuaries and lagoons along the west and south coasts of South Africa. Adult males ofO. gammarellushave slender antennae and characteristic expanded, flattened, oar-like distal segments on pereopod 7. Adult males ofP. platensishave the peduncle of antenna 2 strongly swollen and have bulbous, but not flattened, distal segments on pereopod 7. Both species occur under wrack and other debris along the banks of estuaries and sheltered lagoons.Orchestia gammarellusis found only along the south-west coast, in the Berg River Estuary, Langebaan Lagoon and the Diep River Estuary. Previous records from Knysna were misidentifications ofP. platensis.Platorchestia platensisis found at one west coast site, Langebaan Lagoon, but is widely distributed from Cape Point eastwards to at least Algoa Bay. Both species share the same habitats as several other native beachfleas and competitive interactions between native and introduced species merit investigation. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to document recent additions to the South African barnacle (Cirripedia) fauna. New species records were obtained by examining accumulated collections of unidentified material in the Iziko South African Museum, as well as via material collected directly by the authors. Fourteen species, none of which are new to science, are added to the known fauna, raising the total number of barnacle species recorded from South Africa by over 20%, from 69 to 83 species. Ten of the additional species are offshore benthic forms and represent deep-water taxa whose ranges are extended into South African waters. The remaining four are coastal inshore or surface-dwelling species, of which three are considered recent anthropogenic introductions. The large number of additions to the fauna can be attributed to a long absence of taxonomic expertise on this group in the region and consequent accumulation of unidentified samples. A high proportion of the deep-water samples examined contained previously unreported species, suggesting that additional sampling of hard abyssal substrata in the region is certain to yield yet more new cirripede records. [ABSTRACT FROM AUTHOR]

Numerous authors have cited numbers, or proportions, of endemic species within South(ern) African marine taxa, but comparisons between these statistics are confounded by differing definitions of regional boundaries and differences among data sets analysed. These have resulted in considerable variations in published endemicity data, even within the same taxonomic group. We tabulated and compared key endemicity statistics for regional marine taxa and explained biases in the data sets. The most comprehensive data sets available give overall marine endemicity within the national boundaries of South Africa as 28-33%, but estimates within individual taxa making up these totals vary enormously, from 0% (Aves, Mammalia) to over 90% (Polyplacophora). We also examined published data documenting localised endemicity patterns around the coastline. These consistently show the highest numbers of endemics occurring along the South Coast. There are logical biogeographical reasons to expect this trend, but endemicity rates are also inherently biased by distance from defined political boundaries and by differing sampling effort locally and in neighbouring countries. Range restriction is considered a better measure of conservation status than endemicity, although it is far less often used and yields very different patterns. Properly and consistently calculated measures of national endemicity do, however, retain significant conservation value, and the rates for South African marine biota are high relative to other regions globally, being exceeded only by New Zealand and Antarctica. It is important that when citing endemicity statistics, researchers and conservation managers understand the definitions used and the many constraints under which these measures are derived. [ABSTRACT FROM AUTHOR]

The cushion-star Parvulastra exigua (Lamarck, 1816) is a widely distributed member of the temperate intertidal fauna in the southern hemisphere. In South Africa, it occurs in sympatry with the endemic Parvulastra dyscrita (Clark, 1923), the two species being differentiated predominantly by gonopore placement. Several recent studies have suggested that there may be additional cryptic species within the P. exigua complex in South Africa, based variously on color morphology, genetic evidence and the differential placement of the gonopores. This paper attempts to resolve whether one or more species are represented within P. exigua. A total of 346 P. exigua and 8 P. dyscrita were collected from sites on the west and south- west coasts of South Africa; morphological, anatomical and genetic analyses were performed to determine whether cryptic species and/or P. exigua specimens with aboral gonopores were present. Results show that neither cryptic species nor P. exigua specimens with aboral gonopores occur at these sites. This study thus refutes previous claims of the existence of aboral gonopores in South African P. exigua, and suggests that a single species is represented. The distinction between P. exigua and P. dyscrita is also confirmed, and features separating these two species are clarified and documented. [ABSTRACT FROM AUTHOR]

Brooding behavior and the brooded young of Ophioderma wahlbergii, a common, large, shallow-water brittle star from South Africa, are described for the first time. Monthly samples of 20 specimens were collected from June 2013 to May 2014 (n=240 in total). The species was shown to be gonochoric. Females reached maturity at 17 mm disc diameter (dd), and their ovaries contained 5±3 yolky eggs of mean diameter 0.25±0.1 mm. No seasonal trends in reproduction were found, and >50% of females examined in each month were brooding. Brooding individuals contained an average of 7±6 and up to 33 developing young. Small stages were more frequent than larger young, suggesting that juveniles either emerge at different sizes, or more likely suffer mortality during development. Young within individual adults were of different clutches, but those within individual bursae were all of the same stage. No signs of larval stages were found, indicating that development is direct. Given the large size of emerging juveniles, the species is likely to be matrotrophic and hence truly viviparous. Brooding is a recent discovery in Ophioderma and, so far, the only known brooder has about 1000 small embryos. This study shows quite a different reproductive strategy within the genus, with few, large eggs developing into the largest brooded young known from any species of ophiuroid. [ABSTRACT FROM AUTHOR]

Aim Climate change is expected to drive range shifts among a wide array of organisms. Non-indigenous species ( NIS) provide a unique opportunity to observe the establishment of range boundaries in a way that cannot be directly seen for native species. Recent studies have indicated that climate change facilitates biological invasions at local scales. However, the generality of these effects is unclear, as there is a dearth of comparative studies that assess how rapid environmental change affects species ranges across taxa and biogeographic provinces. Location The South African coast and other coastlines across the world. Methods We first studied the distribution of shallow-marine benthic organisms along the South African coastline and analysed the global distribution of NIS. We then obtained DNA sequence data from a suite of co-occurring NIS from along the studied coastline and compared these data with available genetic information from other regions of the world. Subsequently, we conducted physiological experiments to assess how thermal tolerance was related to species distribution. Finally, we analysed ship-based seawater temperature records and compared these with past changes in the range size and abundance of NIS. These records were used to estimate shipping intensity and NIS propagule pressure. Results We found that NIS with a variety of thermal tolerances and distributions have expanded their ranges and increased in abundance as seawater temperature regimes have changed. We found little interannual variation in shipping transport intensity. Most haplotypes of the studied NIS in South Africa were shared with other regions. Main conclusions This study provides empirical evidence that NIS, regardless of their thermal tolerance, range size and genetic variability, are expanding their ranges and increasing in abundance. This trend is uncorrelated with levels of human-mediated NIS transport but concurrent with changes in seawater temperature, which suggests that climate change fosters the spread and abundance of NIS across multiple spatial scales. [ABSTRACT FROM AUTHOR]

Twenty-two South African shores were surveyed for stranded debris colonized by goose barnacles. The most frequently colonized substrata were kelp (Ecklonia maxima) and plastic, comprising 33.1 and 29.0% of total colonized items, respectively. Four goose barnacle species showed significant preferences for specific substrata: Dosima fascicularis for feathers; Lepas anserifera for rubber sandals; L. pectinata for the shells of dead cephalopods Spirula spirula; and L. testudinata for kelp E. maxima. The other species, L. anatifera and L. australis, did not show significant preference for specific substrata. All species frequently attached to plastic debris. Object size and species were significantly related (P < 0.0001), with D. fascicularis and L. pectinata colonizing relatively smaller objects than other species. Colony size differed significantly between species (P < 0.0001), with D. fascicularis and L. pectinata occurring in relatively smaller colonies and L. testudinata being the only species to regularly occur in colonies ≥1000 individuals. We conclude that the nature and abundance of available substrata greatly influences the abundance and distribution of goose barnacles, and the increasing abundance of plastic is drastically increasing their opportunities to colonize and disperse within the southern African region. [ABSTRACT FROM AUTHOR]

Continental South Africa has a coastline of some 3,650 km and an Exclusive Economic Zone (EEZ) of just over 1 million km2. Waters in the EEZ extend to a depth of 5,700 m, with more than 65% deeper than 2,000 m. Despite its status as a developing nation, South Africa has a relatively strong history of marine taxonomic research and maintains comprehensive and wellcurated museum collections totaling over 291,000 records. Over 3 million locality records from more than 23,000 species have been lodged in the regional AfrOBIS (African Ocean Biogeographic Information System) data center (which stores data from a wider African region). A large number of regional guides to the marine fauna and flora are also available and are listed. The currently recorded marine biota of South Africa numbers at least 12,914 species, although many taxa, particularly those of small body size, remain poorly documented. The coastal zone is relatively well sampled with some 2,500 samples of benthic invertebrate communities have been taken by grab, dredge, or trawl. Almost none of these samples, however, were collected after 1980, and over 99% of existing samples are from depths shallower than 1,000 m-indeed 83% are from less than 100 m. The abyssal zone thus remains almost completely unexplored. South Africa has a fairly large industrial fishing industry, of which the largest fisheries are the pelagic (pilchard and anchovy) and demersal (hake) sectors, both focused on the west and south coasts. The east coast has fewer, smaller commercial fisheries, but a high coastal population density, resulting in intense exploitation of inshore resources by recreational and subsistence fishers, and this has resulted in the overexploitation of many coastal fish and invertebrate stocks. South Africa has a small aquaculture industry rearing mussels, oysters, prawns, and abalone-the latter two in land-based facilities. Compared with many other developing countries, South Africa has a well-conserved coastline, 23% of which is under formal protection, however deeper waters are almost entirely excluded from conservation areas. Marine pollution is confined mainly to the densely populated KwaZulu-Natal coast and the urban centers of Cape Town and Port Elizabeth. Over 120 introduced or cryptogenic marine species have been recorded, but most of these are confined to the few harbors and sheltered sites along the coast. [ABSTRACT FROM AUTHOR]

Background: Brooding brittle stars have a special mode of reproduction whereby they retain their eggs and juveniles inside respiratory body sacs called bursae. In the past, studying this phenomenon required disturbance of the sample by dissecting the adult. This caused irreversible damage and made the sample unsuitable for future studies. Micro X-ray computed tomography (µCT) is a promising technique, not only to visualise juveniles inside the bursae, but also to keep the sample intact and make the dataset of the scan available for future reference. Findings: Seven µCT scans of five freshly fixed (70 % ethanol) individuals, representing three differently sized brittle star species, provided adequate image quality to determine the numbers, sizes and postures of internally brooded young, as well as anatomy and morphology of adults. No staining agents were necessary to achieve high-resolution, high-contrast images, which permitted visualisations of both calcified and soft tissue. The raw data (projection and reconstruction images) are publicly available for download from GigaDB. Conclusions: Brittle stars of all sizes are suitable candidates for µCT imaging. This explicitly adds a new technique to the suite of tools available for studying the development of internally brooded young. The purpose of applying the technique was to visualise juveniles inside the adult, but because of the universally good quality of the dataset, the images can also be used for anatomical or comparative morphology-related studies of adult structures. [ABSTRACT FROM AUTHOR]

This study documents the fauna associated with two common comatulid crinoid species, Comanthus wahlbergi and Tropiometra carlnata, in False Bay, South Africa, and describes the patterns of infestation of obligate associate species. A total of 11 invertebrate species was found associated with one or both crinoids. Of these, three were considered obligate: the myzostomidans, Myzostoma fuscomaculatum and Myzostoma n. sp., and the shrimp, Hippolyte catagrapha, all of which only occurred on T. carinata. Both frequency and density of infestation were higher for the two myzostomes than for the shrimp. The majority of crinoids infested with myzostomes hosted two or more individuals, while H. catagrapha usually occurred singly. A total of 67.5% of all T. carinata collected were infested by symbionts. Of these 45% hosted only one species, 17% hosted two species and 5.8% hosted all three. Most M. fuscomaculatum (85.2%) and H. catagrapha (82.1%) matched their hosts' colouring, while Myzostoma n. sp. were all yellowish in colour. Infestation by Myzostoma n. sp. increased in both frequency and density with depth. All three obligate symbiont species are new to science, illustrating the biodiversity that can still be uncovered by investigating new niches. [ABSTRACT FROM AUTHOR]

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A revised and updated list of South African sea anemones is compiled and the distribution pattern and endemicity of each determined from museum and literature records. Forty-nine valid species are recognized. Species richness appears fairly uniform around the coast, although marked peaks occur at Cape Town, False Bay and Durban - almost certainly the result of disproportionately intense sampling effort at these locations. Forty-nine percent of species are endemic, slightly above the average for the South African marine fauna (31%), but well within the range shown by component taxa. Endemics are absent in the northwest, hut otherwise comprise a fairly consistent proportion of species in each region. The fact that existing records are strongly biased towards a few centres of high sampling activity, indicates a pressing need for additional systematic collection of this group in under-represented areas. [ABSTRACT FROM AUTHOR]

Abstract. Available data on species distributions and endemicity were compiled and examined for 11 groups of South African marine invertebrates (2533 species). For five groups species richness adhered to a well-documented pattern, increasing from west to east, but for the other groups species richness was highest along the south coast. Endemicity was generally highest along the south coast, and lowest along the east coast. The data base was then analysed using several types of complementarity analyses, each producing a minimum set of potential reserve areas, which cumulatively represent all invertebrate species analysed. Approaches based solely on rarity, species richness and endemicity demonstrated individual biases, suggesting a need to combine all three interests. Combining the three techniques produced similar results to the individual analyses, showing conservation priorities to be highest along the east coast. Specifically, the areas of Port Elizabeth and Durban were ranked high in all analyses. Consistently, a total of 16 sites was necessary to represent all species analysed. Comparisons with similar analyses on fish and seaweeds revealed similar findings. Existing invertebrate records were shown to be biased towards centres of high sampling activity, demonstrating a need of future sampling attention in under-represented areas. [ABSTRACT FROM AUTHOR]