Three new species of Levinsenia Mesnil, 1897 (Annelida: Paraonidae) from shallow and deep waters of Southwestern Atlantic Ocean

Three new species of Levinsenia were collected during a benthic survey, from 10–3,000 m deep, in Espírito Santo Basin, off the southeastern Brazilian coast. These species are L. paivai sp. nov., L. blakei sp. nov. and L. lesliae sp. nov. Members of L. paivai sp. nov. are recognized by the presence of nine pairs of well-developed and heavily ciliated branchiae, those of L. blakei sp. nov. are characterized by the presence of three pairs of small branchiae, and those of L. lesliae sp. nov., by the absence of branchiae and presence of notopodial transitional chaetae. These new species are described herein and compared to the most similar congeners. These are the first new species of Levinsenia described from off the Brazilian coast.

Predicting the distribution of a portunid crab in Patagonian coastal waters

Ovalipes trimaculatus is a commercially important, cosmopolitan portunid crab. However, environmental conditions that drive its distribution have never been studied. Thus, we aimed to assess the habitat preferences of this species in northern Patagonia by developing a species distribution model. We obtained spatial quantitative data of the crab and its prey species from a benthic survey performed prior to commercial fishing in the area. We used measurements of environmental condition, biomass, richness and evenness of its prey as predictors, and modeled the density of O. trimaculatus through a delta-gamma model, and produced a map of its predicted biomass. Prey biomass, depth and substrate type were the most important variables for predicting the distribution of O. trimaculatus. The model predicts a restricted depth range, with maximum crab density at 10 m (the shallowest depth sampled) in bottom substrates of relatively fine granulometry, such as silty sand and silt. Prey biomass does not determine crab presence, but, where the crab is present, higher prey biomass correlates with higher crab abundance. Our results accurately predicted 1 of the 2 actual fishing grounds; hence, the model may be a useful tool for local fishers and managers.

Present geoecological transformations in the Kerch strait ecosystem

This study examined the distribution, structure, and dynamics of bottom communities of macrozoobenthos in the Kerch Strait based on an analysis of literature sources from 1934 and 1955, archival data documenting hydrobiological field investigations of the Southern Research Institute of Marine Fishery and Oceanography (YugNIRO, Kerch) in 1986 and 1989, and results of the joint Russian-Ukrainian benthic survey of the Kerch Strait (47 stations) conducted by the Institute of Geography of RAS and YugNIRO in the summer of 2010. It was found that populations of filter-seston feeding bivalves in the strait ecosystem have degraded over the past 75 years, whereas populations of detritus-feeding polychaetes preferring muddy bottoms have become much more abundant. Researchers identified species of bottom animals and strait areas exhibiting maximum changes. An analysis of the dynamics of bottom sediment structure in the strait based on YugNIRO archival data and the results of a 2008 diving survey conducted by the Institute of Geography of RAS (49 divers) demonstrated that the observed transformations are associated with silting of a considerable part of the strait bottom as a result of both earlier and more recent economic activities, particularly the disposal of dredging grounds from 1960 to 1990 and the construction of the Tuzla Dam in 2003, respectively. However, the character of the fixed transformations does not enable us to identify the specified reasons as the sole causes of the changes; therefore, the authors also consider hypotheses explaining other mechanisms. The authors conclude that further research on geoecological dynamics of the Kerch Strait ecosystem is needed, particularly after the construction of the Crimean Bridge.

Coral bleaching in turbid waters of north-western Australia

We report severe bleaching in a turbid water coral community in north-western Australia. Towed still imagery was used for a benthic survey near Onslow in March 2013 to assess thermal stress in hard and soft corals, finding 51–68% of all corals fully bleached in 10–15-m water depth. Tabulate or foliaceous Turbinaria was the locally most abundant hard coral (46%), followed by massives such as faviids and poritids (25%) and encrusting coral (12%), thus over 80% of the local corals could be considered to be bleaching resistant. All coral groups were bleached in similar proportions (massive hard corals 51%<soft corals 60%<encrusting hard corals 62%<Turbinaria 62%<‘others’ 68%). NOAA data and environmental assessments suggest previous recurrent thermal stress throughout the last 10 years in the study area. On the basis of these records this stress apparently changed the community structure from bleaching vulnerable species such as Acropora, leaving more tolerant species, and reduced coral cover. We could see no evidence for adaptation or acclimation of corals in this area. Towed still imagery was found to be a suitable means for rapid and large-scale bleaching studies in shallow, turbid areas where diving can be difficult or impossible.

Armandia sampadae, a new species of polychaete (Opheliidae) from Andaman Sea, Northern Indian Ocean

A new species of polychaete, Armandia sampadae was collected from shallow sandy sediments off Rutland Island (57 m depth) and off North Andaman (52 m depth) during a benthic survey along the continental shelf of Andaman and Nicobar Islands. The major character which distinguishes this species from other members of the genus Armandia is the presence of a pair of large, flattened, rounded, stalked, pigmented, leaf-shaped ventral papillae at the ventral base of the ringed anal funnel and the occurrence of a pair of sub-triangular black pigmented spots in the basal portion of the ventral papillae.

HABITAT HEALTH OF ILOILO RIVER - INSIGHTS FROM A STUDY ON BENTHIC COMMUNITY STRUCTURE

In west central Philippines, the monitoring of aquatic systems traditionally focused on dissolved oxygen values and biological oxygen demand, e.g. monitoring by the Environmental Monitoring Bureau around Panay Island. However, single or two factors are considered to be insufficient to assess habitat health precisely. In this paper, we investigated a benthic community and xamined their implications to habitat health of the Iloilo River. According to a prior benthic survey, warning signs pertaining to biotic, abiotic and community factors have been detected. The disturbed onditions in Iloilo River can be attributed to 3 factors; 1) its inherent topography, where bends serve as sinks for materials; 2) the lack of vigorous water exchange that promotes deposition and hinders complete flushing; and 3) the manner of utilization of the river by the local people. We thus concluded that: 1) monitoring for water parameters only is not enough to get a clear picture of habitat health; and 2) proposed that biotic components should be included for monitoring aquatic system.

Nemerteans in an Irish marine reserve: synopsis of current and historical records

The under-rock guild of nemerteans from Lough Hyne, south-west Ireland was recorded during a long-term benthic survey of the marine reserve. From 2004 to 2014, common nemerteans were recorded annually in late summer for ten historical monitoring sites (each 10 m of shoreline); more comprehensive surveys were completed in 2012 (4126 low-intertidal to shallow-subtidal rocks were turned) and 2014 (1289 rocks turned) with supplementary information in 2015. The bootlace worm,Lineus longissimus,was the most abundant nemertean species. It was significantly more abundant at the extremely shallow East Castle site than the other nine sites; peak populations (across all ten sites) occurred in 2012. The Lusitanian nemerteanParadrepanophorus crassuswas abundant after 2007. To date, 13 nemertean species were recorded with numerous new records for the lough, includingTubulanus annulatus, Micrura purpurea, Ramphogordius sanguineus, Micrella rufaandEmplectonema gracile. Three additional nemertean species were previously recorded, indicating that at least 16 species occur in the lough. Given the low densities and paucity of comprehensive earlier records, we are not able to ascertain definitely whether these species are new incursions or if sparsely distributed residents have increased.