Moonshine worms are a popular bait species used for fishing. The taxon was not detected during surveys of the macrobenthos conducted in Knysna in the 1940s and 1990s, and was first reported as a harvested bait species in the mid-2000s, suggesting that it appeared for the first time in the estuary in the last three decades. A previous molecular analysis identified the worms as Diopatra aciculata, a species first described from Australia. This study provides an updated detailed morphological description of D. aciculata in South Africa to facilitate future identifications and also investigates the species' distribution and population size in the Knysna Estuary. Specimens were examined by scanning electron, stereo- and compound microscopes. Diopatra aciculata has tubes that protrude from the sediment in sandy areas, often decorated with algae and shell fragments; a large body size, up to 600 mm long and 11.5 mm wide. It has 10–18 rings on ceratophores; 5–10 teeth on pectinate chaetae; uni- and bidentate pseudo-compound falcigers and dorsal cirri approximately as long as branchiae. Diopatra aciculata was detected up to 12 km from the mouth of the Knysna Estuary with densities measured at 18 sampled sites. Statistical analysis retrieved high and low density groups that were significantly different from one another (Kruskal-Wallis H(14, 800) = 376.55; P = 0.01), but distribution of high density sites was patchy. We estimate that the population comprises 20–24 million individuals. Given the size of individual worms and the population estimate, this species can be expected to have significant ecological impacts in the estuary.

Background: Atrial fibrillation (AF) is a cause of ischemic stroke and is associated with recurrence and with acute multi-vessel territory non lacunar stroke. Many cryptogenic strokes could be secondary to undiagnosed paroxystic AF. As left atrium (LA) dilatation is a risk factor of AF, we sought to determine if moderate or severe LA dilatation was associated with multiple vascular territory infarcts on magnetic resonance imaging (MRI) in patients with acute ischemic stroke without known AF. Normal LA diameter values are ≤4.0 cm for men and ≤3.8 for women. Methods: Patients who presented at our center between 2006 and 2011 with a diagnosis of acute ischemic stroke (AIS) or transient ischemick attack (TIA) who had a transthoracic echocardiography and a brain MRI were included. Patients with known or de novo AF diagnosed within 3 months of the event were excluded. The main outcome was the presence of acute multi-vessel territory infarct(s) on MRI.Results: 356 patients were included. The mean LA diameter was 37 mm in the control group (normal or mildly dilated LA) and 49 mm in those with moderately to severely enlarged LA (p<0.001). More patients in the LA dilatation group met the main outcome (20% vs 6%; OR 3.89; 95% CI 1.32-11.43; p=0.0014). Conclusions: LA dilatation (at least moderate) is associated with acute non lacunar multiple vascular territory infarcts on MRI in patients with AIS or TIA without known AF or a confirmed diagnosis of AF. Further studies are necessary to determine if this population might benefit from anticoagulation therapy.

Several empty shells of the Rissoid Alvania dorbignyi are found in the sea off Tabarka, north-western Tunisia. Alvania dorbignyi is a species known along Israeli and Cyprus coasts, generally considered to be a lessepsian migrant, but a full agreement on its origin does not currently exist. The present distribution of such species is here discussed, pointing out the lack of intermediate records between samples from Tabarka, here reported, and those from the Levantine Basin. It is emphasized that realistic conclusions will be suggested after an accurate search of the species in such intermediate areas.