Length–weight relationships (LWR) were determined for Deania calceus, Deania profundorum, Merluccius polli, Merluccius senegalensis, Mora moro, Trachyscorpia echinata, and Zenopsis conchifer. Specimens were collected during scientific trawl surveys conducted along the edge of the continental shelf of Morocco and Western Sahara in November–December 2005 and 2006. Fish were measured in relation to total length (TL, to 0.1 cm) and total weight (TW, to 1 g), and sexed when possible. All LWRs obtained for the pooled sexes gave close linear regressions (r2 ≥ 0.93), and LWR parameter b ranged from 2.638 (Z. conchifer) to 3.172 (D. calceus). Data presented herein expand the knowledge base for these species in Northwest Africa, as they have limited or no LWR data publicly available.
A single male specimen of Goneplacid crab, Carcinoplax haswelli (Miers, 1884) is recorded for the first time from the Indian Ocean. The crab specimen was collected from the trawl bycatch landing of the commercial demersal trawler operated between 30 and 150 m depth along the Gujarat coastal region, Northwest coast of India. This C. haswelli is previously recorded from northern Australia and Taiwan to South China Sea. Until now, C. haswelli is not observed or recorded from the Indian Ocean. In the present study, detailed information regarding the taxonomic identification and previous distribution of the goneplacid crab, C. haswelli is described.
The present research documents new distributional records of two gobioid fishes, Acentrogobius vanderloosi Allen, 2015 and Pseudogobius fulvicaudus Huang, Shao, and Chen, 2014 from the southeastern coast of India. Indian coastal waters provide suitable habitats for many gobioid fishes due to its varied ecosystems. The confusion over the identity of a number of gobioid fishes in India suggests the need for more studies on these fishes to better understand their diversity, taxonomy, and geographical distribution. The present record of these species from the southeastern coast of India expands the known distribution of these species.
Intertidal macrobenthos at the small Chernaya Bight (the White Sea) was surveyed six times during 1993–2018 in order to study spatiotemporal variability. Distributions of sediments and macrophytes were highly variable in both space and time, as were most macrofaunal community attributes. Biomass slightly increased with time, while no long-term trends were found in total abundance, diversity, or functional structure. All community attributes were patchily distributed across the beach, and their patterns were not spatially autocorrelated and poorly associated with sediment properties, but changed considerably from year to year. Temporal changes in the community composition were considerable but less substantial compared with the spatial variations. The overall dynamics of species structure did not show any regular trend-like pattern but formed quasicyclic trajectories in ordination space, with nondirectional, spatially noncorrelated fluctuations around some relatively stable state. Comparison with two other neighbouring intertidal sites, studied annually in 1987–2017, showed that macrofauna at every site had similar average biomasses and common dominant species; however, the communities maintained their specificity in structure and exhibited distinct types of dynamics. In particular, the communities demonstrated different long-term trends in total biomass and diversity and followed their own paths in dynamics, appearing as differently oriented interannual trajectories. Nine most abundant species revealed no significant among-site correlations in abundance, and only two bivalve species showed good intersite agreement in dynamics of biomass. We suggest that local benthic communities are largely influenced by site-specific environmental conditions, resulting in independent and even opposite patterns of dynamics in neighbouring localities.