Squat lobsters of the family Munididae of South Africa have been severely neglected with little to no studies done on the group since the turn of the century. Relatively few species are known from the region, which otherwise has a diverse invertebrate fauna, suggesting that the South African munidid diversity has been underestimated. Accumulated material housed in the Natural History Collections of the Iziko South African Museum, some of which had remained there for decades without being identified, as well as samples opportunistically collected during the course of this study, were examined. Morphological analyses and DNA barcoding were used to add to, revise and update records of the regional munidid fauna. One new species of Trapezionida is described, while eight others (four of which are also new generic records for South Africa) are added to the regional fauna. Four other poorly-known species are redescribed and several other dubious records resolved. As a result, the number of munidid species in South Africa is raised from seven to 17. Moreover, a key to the South African munidid fauna is provided. In terms of distribution pattern, only two species were recorded off the west coast, while 15 were found off the east coast. Endemicity was remarkably low at about 6%, with Trapezionida longisandla sp. nov. being the only endemic species, though it likely also occurs outside South African waters. Though greatly enhancing knowledge to this important group, this study also highlights the need for more rigorous sampling and almost certainly more species remain to be discovered from the region.

Squat lobsters of the family Galatheidae are severely understudied in South Africa and have never been the subject of a regional monographic study. The last additions and updates to the fauna were made almost 20 years ago and a revision of this family is thus long overdue. This study adds to, revises and updates the regional fauna based on examination of historic material housed in the Natural History Collections of the Iziko South African Museum, as well as ad-hoc samples collected around the South African coast. A new species of Galathea Fabricius, 1793 is described and illustrated, while three other species are added to the regional fauna and several dubious records resolved. The taxonomic status of Galathea labidolepta Stimpson, 1858 is confirmed and the species redescribed, with a neotype being assigned to replace the holotype lost in the 1871 Chicago fire, and a species of the genus Lauriea Baba, 1971 is reported for the first time from the country. A dichotomous key for identification of all species found in South Africa is also included. Although this study adds substantial knowledge on the group, it also highlights the need for more rigorous sampling in South Africa.

Gastropods of the echinoderm-parasitic family Eulimidae show extraordinarily high ecological diversity. A combination of the three types of parasitism (temporary, ecto- and endoparasitism) and the five classes of extant Echinodermata allows us to identify 15 potential categories of parasitic association, all but 1 of which have already been documented. Here, we describe the last remaining category by recording the first endoparasitic eulimid in the Ophiuroidea, Introphiuricola rebeccae n. gen., n. sp., from the bursal sac of the brooding brittle star Amphiura capensis (Amphiuridae) in Cape Town, South Africa. This new eulimid is characterized by (1) a globose pyriform shell up to 1.8 mm high with a blunt apex; (2) large body whorl occupying >= 90% of the total shell height; (3) large, drop-shaped aperture with a simple prosocline outer lip; (4) brownish, dorsoventrally depressed pupiform protoconch; (5) large epipodial flap on either side of the foot; (6) endoparasitic mode of life in an ophiuroid; (7) probable protandrous sequential hermaphroditism; and (8) direct early development with no pelagic larval period. A molecular phylogenetic reconstruction reveals its close relationship to certain temporary parasites of ophiuroids with slender shells in the genera Helimiostraca, Eulima and Pyramidelloides. Its distant relationship to Stilifer, a group that also has a globose shell and lives inside asteroids, suggests an independent endoparasitic origin of the globose shape for different hosts. Benthic early development shared by the present ophiuroid and eulimid implies that this host-parasite interaction has arisen locally and remains endemic to South Africa and perhaps also Mozambique.

Abstract 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.

The Galeommatoidea are a diverse but little-studied group of small bivalves, well known for the symbiotic relationships many species have with a range of invertebrate taxa. Four species collected from the Western Cape region of South Africa were examined and illustrated, providing new details on their habitat preferences, and depicting the mantle structure of live specimens for the first time. Brachiomya ducentiunussp. nov., is described herein, and an additional record of Montacuta substriata (Montagu, 1808) is reported from South Africa. Brachiomya ducentiunus and Montacuta substriata have obligate symbiotic relationships with different burrowing echinoids, while Kellia becki (WH Turton, 1932) and Melliteryx mactroides (Hanley, 1857) are free-living. DNA data and phylogenetic analyses are provided for three of the species.

Kelp forests along the southwestern and west coasts of South Africa, dominated by the species Ecklonia maxima and Laminaria pallida , are locally termed ‘the Great African Seaforest’. They form 3-dimensional biogenic habitats that provide 4 distinct microhabitats—canopy, fronds, stipe and holdfast—with the latter typically supporting the highest abundance and diversity of associated macroinvertebrates. The macrofauna inhabiting kelp holdfasts in South Africa have rarely been studied, resulting in a near complete lack of baseline data. In this study, macrobenthic assemblages from 40 E. maxima holdfasts were examined over 2 marine ecoregions and 4 locations. Macroinvertebrates were identified and counted for univariate and multivariate analyses using family-level data. A total of 120 families from 9 phyla were identified and were generally dominated by Arthropoda (48 families), Annelida (24 families) and Mollusca (23 families). Marine ecoregion had no significant effect on composition of macroinvertebrate assemblages, whereas location had a significant effect. There was no significant relationship between holdfast volume and macroinvertebrate diversity or abundance, suggesting that other environmental and physicochemical factors are important in determining community structure. This study serves as a baseline for future research aimed at understudied holdfast macroinvertebrate communities in the Great African Seaforest.

Many shark and ray species show affinity to specific sites, making these areas critical for their survival. These include cleaning stations: locations on reefs where cleaner fish remove parasites and clean wounds, which is important for maintaining health. Cleaning stations also function as social gathering sites, or resting points, where courtship and mating can occur. In this study, we identify an aggregation site for the shortfin devil ray, Mobula kuhlii (Family Mobulidae) within the Aliwal Shoal Marine Protected Area in KwaZulu-Natal (KZN), South Africa, and document their behavior. Remote underwater video was used to collect footage of M. kuhlii being cleaned by blue streak cleaner wrasse, Labroides dimidiatus. Generalized additive models (GAMs) were used to assess environmental predictors of M. kuhlii presence on Aliwal Shoal. Mixed models were used to assess the same environmental predictors and their correlation with mean M. kuhlii cleaning duration and number of L. dimidiatus bites per second at the identified cleaning station site. M. kuhlii were present in 56

Research on the composition and distribution patterns of intertidal biota has focused mostly on either sandy or rocky shores, with much less work on boulder shores and almost none on shores of particle grain sizes between 1 -< 256 mm. Recent studies have shown, however, that pebble (4-64 mm) and cobble (65-256 mm) shores comprise a very distinct habitat type, sheltering a biota less than 10% similar to those of either sandy, or boulder and rocky shores. This paper examines the composition and distribution patterns of the biota of seven pebble and five cobble shores along the South-Western coastline of South Africa, each surveyed by sampling a transect of eight equally-spaced 20 x 20 cm quadrats from low to high shore. Overall, 39 taxa were recorded, but only 14 occurred more than once and are thus considered characteristic of pebble and cobble habitats. The biota comprised many species typical of hard-substrata, some typical of sandy beaches, and a few unique to pebble and cobble habitats. Dominant species were mostly air-breathing Arthropoda, plus one pulmonate Gastropoda. Macro-algae were notably absent. Unlike the burrowing species of sandy shores, or attached species of rocky and boulder shores, pebble and cobble shore species were almost all motile, no doubt to withstand the mobility of rolling grains. Also, unlike most other intertidal shores, the fauna was concentrated around the high shore, where food was most available in the form of drift kelp. Some air-breathing species migrated well into the intertidal at low tide, but presumably retreat above the high-water mark during high tide.

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.

In South Africa, anthropogenic pressures such as water over-abstraction, invasive species impacts, land-use change, pollution, and climate change have caused widespread deterioration of the health of river ecosystems. This comes at great cost to both people and biodiversity, with freshwater fishes ranked as the country’s most threatened species group. Effective conservation and management of South Africa’s freshwater ecosystems requires access to reliable and comprehensive biodiversity data. Despite the existence of a wealth of freshwater biodiversity data, access to these data has been limited. The Freshwater Biodiversity Information System (FBIS) was built to address this knowledge gap by developing an intuitive, accessible and reliable platform for freshwater biodiversity data in South Africa. The FBIS hosts high quality, high accuracy biodiversity data that are freely available to a wide range of stakeholders, including researchers, conservation practitioners and policymakers. We describe how the system is being used to provide freshwater fish data to a national conservation decision-support tool—The Department of Forestry, Fisheries, and the Environment (DFFE) National Environmental Screening Tool (NEST). The NEST uses empirical and modelled biodiversity data to guide Environmental Impact Assessment Practitioners in conducting environmental assessments of proposed developments. Occurrence records for 34 threatened freshwater fishes occurring in South Africa were extracted from the FBIS and verified by taxon specialists, resulting in 6 660 records being used to generate modelled and empirical national distribution (or sensitivity) layers. This represents the first inclusion of freshwater biodiversity data in the NEST, and future iterations of the tool will incorporate additional freshwater taxa. This case study demonstrates how the FBIS fills a pivotal role in the data-to-decision pipeline through supporting data-driven conservation and management decisions at a national level.

First-time observations of courtship behaviour of the Endangered shortfin devil ray Mobula kuhlii are described from the Aliwal Shoal Marine Protected Area (MPA), KwaZulu-Natal, South Africa. Three events of M. kuhlii courtship, called 'mating trains', were recorded on video during the months of November 2020 and January 2021. These included a near-term pregnant female, and two lead females followed by up to four males. The common behaviours associated with courtship were documented: multiple males following a single female, rapid speed bursts, avoidance of the female, and swerving. This study confirms that M. kuhlii mating occurs in KwaZulu-Natal waters and that courtship is similar across mobulids. The findings demonstrate the importance of the habitat provided by the Aliwal Shoal MPA for this currently unprotected species.

Manta rays (Mobula alfredi and M. birostris) are poorly understood in South Africa, despite their ecological importance and charismatic appeal. This study analyzed a 41-year dataset from the KwaZulu-Natal bather protection program to investigate catch per unit effort between 1981-2021. We used Generalized Additive Models and the probability of encounter to assess annual and seasonal trends, as well as the effect of location and moon phases on catch rates. We also evaluated the size composition and demographics of caught manta rays using the same dataset. Our analysis revealed a significant decline in overall manta ray catches since the late 1990s (p<0.0001), with increased catch rates during summer, suggesting seasonal visitation to South African waters. We found that manta rays were caught at least once in all 46 netted beaches along the 350 km span of coastline, but with significantly more catches in the Central Area, between Anstey’s beach in the north and Mtwalume in the south. We also observed that moon phase had an effect on manta ray presence, with significantly more catches during spring tides at new and full moon phases. Over half of the caught individuals were juveniles, and a total of 841 individuals (52% of the total catch) belonged to the confirmed juvenile size class (1400-2500 mm disc width). We further found that a greater proportion (70%) of juveniles were caught in the southernmost sampled area, from Hibberdene in the north to Mzamba in the south. These findings highlight the importance of South African waters as a seasonal habitat for manta rays along the southern African coastline. The significant decline and spatial-temporal patterns we observed have critical implications for management and conservation efforts. Our study provides valuable baseline data for future research and underscores the need for continued monitoring and protection of these iconic marine species.

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.

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.

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.

New and notable stomatopods are reported on and added to the Mozambican faunal list, based principally on material housed in the collections of the Iziko South African Museum. Seven species are reported for the first time from Mozambican waters including one undescribed species of Clorida Eydoux & Souleyet, 1842, bringing the total known Mozambican stomatopod fauna to 22 species, comprising 17 genera and eight families. The known fauna is tabulated and taxonomic accounts of eight species are given, seven of these representing the new species records including one undescribed species, while the eighth species account is of the previously poorly documented Erugosquilla woodmasoni (Kemp, 1911), which is reported on from unpublished material. The new record of Manningia australiensis Manning, 1970 represents the first record of the family Eurysquillidae from southern Africa.

Microbial communities are found throughout the biosphere, from human guts to glaciers, from soil to activated sludge. Understanding the statistical properties of such diverse communities can pave the way to elucidate the common mechanisms ...Multiple ecological forces act together to shape the composition of microbial communities. Phyloecology approaches—which combine phylogenetic relationships between species with community ecology—have the potential to disentangle such forces but are often ...

The recently described amphipod Sunamphitoe roberta lives only on the kelp Ecklonia maxima, where it excavates slit-like burrows along the distal margins of thicker primary fronds. Oval chambers along the bases of these slits may represent feeding areas. As burrowing proceeds, the damage progressively erodes back the frond margins, giving them characteristic attenuated and irregular profiles, and probably impacting secondary frond survival and growth, and hence kelp productivity. A kelp forest in False Bay, South Africa, was surveyed to determine what proportion of kelp was infected as well as which individuals were selected as hosts. Forty kelp heads were also dissected to ascertain numbers of amphipods per host and their size composition, and to document details of burrow structure. Of 305 adult kelps inspected, 117 (38.4%) showed visible amphipod damage. Rate of infestation was not correlated with stipe length but was positively correlated with head circumference and negatively correlated with the proportion of secondary fronds remaining. The 40 kelp heads dissected contained 786 S. roberta specimens. These comprised 154 adults (>8 mm), including 33 ovigerous females, and 632 juveniles (<8 mm). The number of amphipods per host ranged from 1 to 112 (mean 19.7 [SD 25.1]). Size distribution was bimodal, and the largest individual measured 20 mm.

This report adds five previously unreported species to the decapod crustacean fauna of South Africa, as well as removing one species previously listed in error. It also documents locality (and/or reference specimen) data for 12 other species, most of which had been depicted in regional field guides, but without reporting when and where they had been collected. Almost all the species added were already known from adjacent African countries and their ranges are here extended into South Africa. Although some of these records are based on photographs, rather than collected specimens, it is argued that such records should be accepted as adequate evidence for inclusion of at least visually-distinctive crustacean species into the regional fauna.