Indian Journal of Geo-Marine Sciences (IJMS)

GIS-based mapping of the spatio-temporal distribution of Reeve’s croaker, Chrysochir aurea (Richardson, 1846), along the coast of West Bengal, India

S Jana — 2026-04-08

The current study used GIS mapping to identify potential fishing areas for Chrysochir aurea (Richardson, 1846), a commercially important sciaenid species, along the coast of West Bengal, India, by analysing its spatio-temporal distribution and abundance. Data were collected from two purposively selected trawlers operating along the coast of West Bengal from October 2021 to September 2022. Chrysochir aurea was found to be distributed at depths ranging from 10 m to 67 m, with the largest catch per hour value (19.07 kg h^-1) occurring at depths ranging between 10 m and 30 m. The maximum catch was recorded in the southeast, which is regarded as a potential fishing zone along the coast. The predictive maps inferred that the species is more prevalent in the southeast region during pre-monsoon and both southeast and southwest regions during post-monsoon and winter seasons. Spatio-temporal distribution of C. aurea, recorded in the present study, will not only help in identifying the potential fishing grounds but also in framing management strategies for sustainable fisheries along the West Bengal coast.

Biometric analysis of rainbow sardine, Dussumieria acuta Valenciennes, 1847 from Andaman Waters

A Mohan — 2026-04-08

The present study aimed to generate baseline biometric data of rainbow sardine Dussumieria acuta from the Andaman Islands. A total of 127 specimens were analysed to examine meristic and morphometric characters, while 939 specimens were used to assess sex ratio, length-weight relationship, and relative condition factor. Eight meristic and twenty-eight morphometric characters were recorded for the current study. Based on the current study of meristic characters, the fin formula for D. acuta can be represented as follows: B_14-15D_18-19P₁₄V₈A_14-15C₁₉G_{(10-11)+(21-22)}. The coefficient of correlation (r) ranged from 0.536 to 0.983 for total length against different morphometric characters and from 0.724 to 0.785 for head length against different morphometric characters. After applying a log transformation, the pairwise linear regression between total length and various morphometric variables indicated that most characters' 'b' value was close to unity. The male-to-female ratio in the above species showed no significance difference from the theoretical 1:1 ratio. The length-weight relationship for D. acuta was expressed as W = 0.0053L^3.1822 for pooled samples, W = 0.0049L^3.2109 for males, and W = 0.0063L^3.116 for females. The relative condition factor (K_n) was close to an ideal threshold value in both males and females and across all seasons.

Biometric analysis of Whipfin silverbiddy, Gerres filamentosus Cuvier, 1829 from Ratnagiri coast of Maharashtra, India

M B Shetkar — 2026-04-08

The Whipfin silverbiddy, Gerres filamentosus Cuvier, 1829 is exploited by beach seines, bottom trawls, long lines, stake nets and gillnets at Ratnagiri in Maharashtra. Morphometric characters, Length-Weight Relationship (LWR) and condition factor of the G. filamentosus were studied from 506 specimens comprising 242 males, 229 females and 35 indeterminants. The coefficient of correlation of total length against other morphometric characters of G. filamentosus ranged between 0.807 (vs. snout length) to 0.994 (vs. standard length). All morphometric measures had a high and moderate degree of correlation with total length. The LWR indicated positive allometric growth. The coefficient of correlation (r) for the LWR was estimated at 0.9824, 0.9760, 0.9839 and 0.9826 for the males, females, indeterminants and pooled data, respectively. Furthermore, the condition factor indicated that the species remained in good condition throughout the year for both sexes, except during August.

First record of machine gun coral shrimp, Coralliocaris graminea (Dana, 1852) (Caridea: Palaemonidae) from Lakshadweep archipelago, Arabian Sea with a key to the genus Coralliocaris Stimpson, 1860

U P Mohammed Naeem — 2026-04-08

Machine gun coral shrimp, Coralliocaris graminea, is reported for the first time from Lakshadweep, India, based on two specimens collected during low tide at a depth of 2 feet from Agatti Island. Globally, C. graminea was reported from the Eastern and Southern Indian Ocean, Gulf of Aden, Pacific Ocean and the Persian Gulf. However, the occurrence of C. graminea has not been reported from the Arabian Sea. In this context, the present study provides a new distributional record of C. graminea from the Lakshadweep Islands, India. Detailed information about the taxonomic identification of the species, taxonomic remarks, and previous distribution is discussed.

An opportunistic encounter with a pod of Short-finned pilot whales (Globicephala macrorhynchus Gray, 1846) in the Lakshadweep archipelago

K Madhu Magesh — 2026-04-08

Observations of short-finned pilot whales (Globicephala macrorhynchus) in the wild are relatively infrequent. This study reports an opportunistic live sighting recorded on 12 February 2024 in the Lakshadweep Islands of the southeastern Arabian Sea, based on vessel-based visual observations conducted aboard FORV Sagar Sampada. The sightings occurred (10°43′74ʺ N; 73°27′35ʺ E), a small pod of six individuals, each approximately 3 m in length at 1800 m depth. Environmental conditions at the sighting location were evaluated using both on-field and satellite-sourced datasets. Sea surface temperatures (SST) ranged between 29 and 31.5 °C, while salinity values indicated moderately stable oceanic conditions. Chlorophyll concentrations were relatively low, signifying oligotrophic surface waters during the observation period. These environmental characteristics may influence prey availability and influence the habitat use by short-finned pilot whales in the southeastern Arabian Sea.

Rediscovery of a deep-water paguroid crab Xylocheles miersi (Alcock & Anderson, 1899) (Decapoda: Anomura) from the Andaman Sea, India

S Tiwari — 2026-04-08

This paper reports the rediscovery of a rare deep-water pylochelid hermit crab, Xylocheles miersi (Alcock and Anderson, 1899), from the Indian Exclusive Economic Zone based on a specimen collected off Narcondam Island, the Andaman Sea, using a High-Speed Demersal Trawl at a depth of 300 m. This is the second record of this species from the type locality. Detailed photographs of the morphological characters of the present specimen and its DNA barcodes of the partial mitochondrial COI and 16S rRNA genes are provided herein.