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The Atlantic brief squid. Lolliguncula brevis, is a euryhaline cephalopod that inhabits shallow, continental shelf habitats from Argentina to the Bay of Fundy. In the southeastern United States, brief squid can account for a considerable portion of the estuarine animal biomass and are an important component of the diets of species with high priority for management and conservation. Historical data from South Carolina Department of Natural Resources suggest that brief squid exhibit spatially and temporally variable size-frequency distributions within the Charleston Harbor estuary. Prior to this study, however, detailed life history information for this species was lacking in the region. Samples of brief squid were collected monthly at four stations along a salinity gradient within the Charleston Harbor estuary in 2019 to investigate temporal and spatial patterns of abundance, sex, size, and maturity. Season and station were significantly related to brief squid abundance, which was greater for all sexes in spring, summer, and fall than in winter. Catches of brief squid were dominated by immature squid compared with mature squid. Excluding sexually indistinct squid, and across all seasons, significantly more males were collected than females. Mean brief squid size tended to be larger in May than in several other months of the year, largely due to the lower abundance of small squid in that month. Logistic regression analyses indicated that brief squid size-at-maturity occurred at 50.2 mm for males and 59.2 mm for females. The presence of both small and large brief squid throughout the year at all stations supports a pattern of overlapping cohorts, whereas the continual presence of immature brief squid at all stations suggests asynchronous recruitment. This study provides valuable life history information that can be used to support the conservation and management of organisms that are either prey or predators of brief squid within the Charleston Harbor estuary. Further research over multiple years and within other estuaries in the Georgia Bight is needed, however, to determine how the life history patterns observed in this study apply more broadly across the region. KEY WORDS: asynchronous, cohort, demographics, phenology, recruitment, Lolliguncula brevis, INTRODUCTION The life history of a population of organisms is defined by how resources are traded off and invested in anatomical, physiological. or behavioral traits that influence patterns of survival [...]

Knowledge of juvenile recruitment (defined here as the quantitative addition of early benthic life stages to a local population) is important for conserving heavily harvested species and their critical habitats. Stone crabs (genus Menippe) are commercially and ecologically important throughout the Gulf of Mexico nearshore waters off Florida, but very little is known about their recruitment. Using standard commercial stone crab traps, megalopal and postsettlement juvenile (collectively, youngof-the-year. 'YOY') stone crabs were sampled at multiple spatial scales and for multiple stone crab generations to characterize geographical, seasonal, and interannual variation in their distribution and relative abundance (numbers collected on traps) in the Gulf of Mexico off peninsular Florida and north of the Florida Keys (the 'Florida Gulf'). The influences of potentially relevant oceanographic and biological variables [temperature, salinity, benthic community on the traps (trap fouling community). depth, distance from shore] on YOY stone crabs were investigated at locations distributed throughout the study area. Trap fouling communities had never been analyzed in detail prior to this study; an importance index was developed to quantify the seasonality, commonality, and density of the fouling communities and organisms composing the communities. Continuous, long-term data from the Tampa Bay location allowed investigation of the effects of biological relationships [relative abundance of female Menippe carrying eggs (ovigerous). occurrences of red tide (Karenia brevis, a toxic dinoflagellate) blooms] and meteorological events [tropical cyclones. El Nino Southern Oscillation (ENSO) occurrences] on temporal patterns of variation in recruitment. High relative abundances of YOY stone crabs were collected off peninsular Florida from dense, complex benthic biota that grew on crab traps located off large, pristine estuaries in relatively turbid water less than 5 m deep, where salinity ranged 24-36 and water temperature averaged 29[degrees]C-32[degrees]C. Two major recruitment locations, stable through decades, consistently accounted for approximately 50% of the YOY stone crabs collected: two secondary recruitment locations similarly accounted for another 25%. Relative abundance of YOY stone crabs was highest nearshore at the major recruitment locations, particularly during years of high relative abundance. Approximately 65%-75% of the recruits were collected August to October; however, the timing of both peak relative abundance and lowest relative abundance shifted to later in the year as latitude decreased. Patterns of change among months in relative abundance differed among locations within years and among years within locations. Water temperature, salinity, and trap fouling community were the important determinants of temporal and spatial variation in YOY stone crab relative abundance: depth and distance from shore were also important in areas where they varied notably among stations within locations and across broader expanses of the study area. At Tampa Bay, a sharp increase in relative abundance of ovigerous females in spring was followed by a similarly sharp increase in YOY stone crab relative abundance (principally stage 3-5 crabs) 3 mo later; whereas a sharp decrease in ovigerous female relative abundance in autumn was followed by a similarly sharp decrease in YOY stone crab relative abundance 1 mo later. Coincidence of the normal autumnal decrease in YOY stone crab relative abundance with red tides and tropical cyclones prevented assigning clear relationships between seasonal change in relative abundance and these potential external influences. Annual decreases in relative abundance were significantly related to the occurrence of tropical cyclones that came near Tampa Bay during the previous year. Twice, confluences of multiple hurricanes. timely red tides, and ENSO events were followed by nearly complete. 1- to 2-y recruitment collapses. In contrast, a single meteorologically and oceanographically highly anomalous year coincided with exceptionally high abundances of both YOY and ovigerous female stone crabs. A relationship between YOY stone crabs and subsequent fishery harvest was not evident, possibly due to a variety of fishery practices. Because stone crabs are subjected to intense fishing pressure throughout the Florida Gulf, the YOY stone crab recruitment grounds and their associated estuaries should be protected from the effects of development. agriculture, aquaculture. and commercial and recreational crabbing. KEY WORDS: abundance, depth, distance from shore, distribution. ENSO events, fishery, Florida, geographic variation. Gulf of Mexico, juveniles, megalopae, Menippe, ovigerous female crab, recruitment, red tide, salinity, seasonality, stone crab. Tampa Bay. temperature, trap fouling, INTRODUCTION Understanding the recruitment patterns of mobile marine benthic invertebrates with pelagic larval dispersal is important because the distribution and abundance of early benthic life stages can greatly influence a [...]

Deposits in dry lake basins of the Aminuis region, south-western Kalahari, Namibia, contain abundant sepiolite. Thin-section observations show that it occurs as part of the groundmass, for which an authigenic origin is implied by the lack of a source for detrital sepiolite. The deposits also contain common sepiolite coatings, which are nearly exclusively illuvial rather than the result of mineral authigenesis in pores. Other sepiolitic pedofeatures are (i) carbonate depletion hypocoatings, locally disturbed by development of porostriation; (ii) surface crusts, formed by re-suspension and settling of fine material after flooding, occurring at sites where low salinity allows their preservation; and (iii) common fragments of coatings, produced by physical or biogenic disturbance, in deposits with an often strongly fragmented microstructure. This study illustrates the need to consider an illuvial or depletion-related nature of sepiolite and palygorskite occurrences along pores in soils, as an alternative for the possibility of clay neoformation. Additional keywords: soil genesis, soil mineralogy., Introduction Sepiolite ([Mg.sub.4][Si.sub.6][O.sub.15][(OH).sub.2].6[H.sub.2]O) and palygorskite ([(Mg, A1)].sub.2] [Si.sub.4][O.sub.10](OH).4[H.sub.2]O) are common clay minerals in soils and surface sediments in semi-arid regions, where they occur in conditions that favour authigenesis of magnesium [...]