Glycera sheikhmujibi n. sp. (Annelida: Polychaeta: Glyceridae): A New Species of Glyceridae from the Saltmarsh of Bangladesh

Cyclone exposure mapping in coastal Bangladesh: A multi-criteria decision analysis

Owing to its geographical location, Bangladesh is highly exposed to natural disasters: the northern part is at risk of floods, while the southern part suffers from cyclones, storm surges, and salinity intrusion. This study aims to quantify the exposure to cyclones in Taltali, a southern coastal upazila of Bangladesh. To quantify the exposure, the study used 6 criteria, including elevation, slope, proximity to major water bodies, population density, proximity to cyclone tracks and land use and land cover, and produced maps focusing on each criterion. The overall exposure map was also created to observe the whole scenario of the upazila. All the analysis was done in a GIS environment using the Analytic Hierarchy Process (AHP) method. The individual criterion map represents the status of the study area in different classes. And the overall exposure map revealed that about 60 % of the study area was quantified as very highly exposed to cyclones, including 4 unions- Barabagi, Chhota Bagi, Karaibaria, Pancha Koralia and 6 Rakhain paras- Taltali, Monukhe, Momeshi, Agathakur, Saton, and Sawdagar. In numerical terms, about 8032 ha and 178 ha of land are counted as highly and moderately exposed to cyclones, respectively. Among the seven unions, the maximum area of the Barabagi and Chhota Bagi was found to be very highly exposed, followed by Panchakoralia and Karaibaria. Data from our previous study also validated the results of this study. Despite having some limitations, the study can be used to develop the capacity of the community to respond to cyclones. And the national and international communities can use the results to formulate policies regarding disaster risk reduction and risk mitigation.

On the Diversity of Phyllodocida (Annelida: Errantia), with a Focus on Glyceridae, Goniadidae, Nephtyidae, Polynoidae, Sphaerodoridae, Syllidae, and the Holoplanktonic Families

Phyllodocida is a clade of errantiate annelids characterized by having ventral sensory palps, anterior enlarged cirri, axial muscular proboscis, compound chaetae (if present) with a single ligament, and of lacking dorsolateral folds. Members of most families date back to the Carboniferous, although the earliest fossil was dated from the Devonian. Phyllodocida holds 27 well-established and morphologically homogenous clades ranked as families, gathering more than 4600 currently accepted nominal species. Among them, Syllidae and Polynoidae are the most specious polychaete groups. Species of Phyllodocida are mainly found in the marine benthos, although a few inhabit freshwater, terrestrial and planktonic environments, and occur from intertidal to deep waters in all oceans. In this review, we (1) explore the current knowledge on species diversity trends (based on traditional species concept and molecular data), phylogeny, ecology, and geographic distribution for the whole group, (2) try to identify the main knowledge gaps, and (3) focus on selected families: Alciopidae, Goniadidae, Glyceridae, Iospilidae, Lopadorrhynchidae, Polynoidae, Pontodoridae, Nephtyidae, Sphaerodoridae, Syllidae, Tomopteridae, Typhloscolecidae, and Yndolaciidae. The highest species richness is concentrated in European, North American, and Australian continental shelves (reflecting a strong sampling bias). While most data come from shallow coastal and surface environments most world oceans are clearly under-studied. The overall trends indicate that new descriptions are constantly added through time and that less than 10% of the known species have molecular barcode information available.