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9. Insights into the divergent evolution of the oceanic squid Sthenoteuthis oualaniensis (Cephalopoda: Ommastrephidae) from the Indian Ocean.

Author

JEENA, Nikarthil S., SAJIKUMAR, Kurichithara K., RAHUMAN, Summaya, RAGESH, Nadakkal, KOYA, K. P. Said, CHINNADURAI, Shunmugavel, SASIKUMAR, Geetha, and MOHAMED, Kolliyil S.

Subjects
SYMPATRIC speciation, CEPHALOPODA, SQUIDS, VICARIANCE, HAPLOTYPES, MOLECULAR phylogeny
Abstract

Sthenoteuthis oualaniensis is known for its complex population structure with three major transoceanic forms (viz. middle‐sized, dwarf, and giant forms) whose taxonomic status has been disputed for decades. This integrated taxonomic study examines these prevenient morphotypes gathered on cruises in the Indian Ocean to ascertain their status in the evolutionary history of the species. Molecular analyses employing mitochondrial (COI, ND2) and nuclear (H3) markers revealed four genetically distinct and novel lineages of the species in the Indian Ocean, representing three morphotypes from the Arabian Sea and one from the Southern Indian Ocean. The mitochondrial‐based phylograms revealed two distinct clades in the species: "dwarf forms + giant form" and "middle‐sized forms," which further branch into geographically structured evolutionary units. Species delimitation analyses recovered five distinct clades, namely, the Arabian Sea giant and dwarf forms, Equatorial, Eastern Typical, and Other Middle‐sized forms, representing the consensus molecular operational taxonomic units. H3 being heterozygous could not resolve the phylogeny. Haplotype network and AMOVA analysis of mtDNA genes indicated explicit phylogeographic structuring of haplotypes, whereas these outputs and PCA results were incongruent with the morphological grouping. Phenetic features distinguishing the morphotypes were sometimes plastic and mismatched with the genotypes. The giant form was genetically close to the dwarf forms, contradicting the earlier notion that it descended from the middle‐sized form. It may be assumed that the dwarf form evolved following sympatric speciation and adaptation to warm equatorial waters, while the focal features of the Western Arabian Sea guide toward allopatric speciation of the giant form. [ABSTRACT FROM AUTHOR]

Published
2023
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13. Characterisation of an individual of the giant form of the purpleback flying squid Sthenoteuthis oualaniensis (Cephalopoda: Ommastriphidae) in the Arabian Sea and its biological descriptors

Author

Sajikumar, Kurichithara K., primary, Najmudeen, Theparambil M., additional, Ragesh, Nadakkal, additional, Jeena, N. S., additional, Rahuman, Summaya, additional, Sunil, K. T. Sadanandan, additional, Sasikumar, Geetha, additional, and Mohamed, Kolliyil S., additional

Published
2021
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14. First Record of the Thai Bobtail Squid, Euprymna hyllebergiNateewathana, 1997 (Cephalopoda: Sepiolidae) from the Arabian Sea

Author

Venkatesan, Vellathi, Sajikumar, Kurichithara K., Jeena, Nikarthil S, Rahuman, Summaya, Alloycious, Puthenpurakkal S., Jestin Joy, Konnoth M., Mohamed, Kolliyil S., and Sasikumar, Geetha

Abstract

The small benthic squid Euprymna hyllebergiis reported for the first time from the southeastern Arabian Sea along the Indian coast. A total of 97 individuals (56 females and 41 males) were collected from commercial trawls. The dorsal mantle length (DML) of the individuals ranged from 21 to 46.5 mm for males and 24 to 50 mm for females. This species has previously been reported only from the Persian Gulf, the Gulf of Thailand, and the Andaman Sea. Detailed morphometric, meristic, and molecular data for this species are provided. The documentation of this squid from India expands the catalogue of cephalopod fauna of the Arabian Sea, shedding new insights on its distribution patterns.

Published
2023
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16. Status of Indian marine fish stocks: modelling stock biomass dynamics in multigear fisheries

Author

Sathianandan, T V, primary, Mohamed, Kolliyil Sunil, additional, Jayasankar, Jayaraman, additional, Kuriakose, Somy, additional, Mini, K G, additional, Varghese, Eldho, additional, Zacharia, P U, additional, Kaladharan, P, additional, Najmudeen, T M, additional, Koya, Mohammed K, additional, Sasikumar, Geetha, additional, Bharti, Vivekanand, additional, Rohit, Prathibha, additional, Maheswarudu, G, additional, Sindhu, K Augustine, additional, Sreepriya, V, additional, Alphonsa, Joseph, additional, and Deepthi, A, additional

Published
2021
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21. World Octopus Fisheries

Author

Sauer, Warwick H. H., primary, Gleadall, Ian G., additional, Downey-Breedt, Nicola, additional, Doubleday, Zöe, additional, Gillespie, Graham, additional, Haimovici, Manuel, additional, Ibáñez, Christian M., additional, Katugin, Oleg N., additional, Leporati, Stephen, additional, Lipinski, Marek R., additional, Markaida, Unai, additional, Ramos, Jorge E., additional, Rosa, Rui, additional, Villanueva, Roger, additional, Arguelles, Juan, additional, Briceño, Felipe A., additional, Carrasco, Sergio A., additional, Che, Leo J., additional, Chen, Chih-Shin, additional, Cisneros, Rosario, additional, Conners, Elizabeth, additional, Crespi-Abril, Augusto C., additional, Kulik, Vladimir V., additional, Drobyazin, Evgenyi N., additional, Emery, Timothy, additional, Fernández-Álvarez, Fernando A., additional, Furuya, Hidetaka, additional, González, Leo W., additional, Gough, Charlie, additional, Krishnan, P., additional, Kumar, Biju, additional, Leite, Tatiana, additional, Lu, Chung-Cheng, additional, Mohamed, Kolliyil S., additional, Nabhitabhata, Jaruwat, additional, Noro, Kyosei, additional, Petchkamnerd, Jinda, additional, Putra, Delta, additional, Rocliffe, Steve, additional, Sajikumar, K. K., additional, Sakaguchi, Hideo, additional, Samuel, Deepak, additional, Sasikumar, Geetha, additional, Wada, Toshifumi, additional, Zheng, Xiaodong, additional, Tian, Yongjun, additional, Pang, Yumeng, additional, Yamrungrueng, Anyanee, additional, and Pecl, Gretta, additional

Published
2019
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22. Relating abundance of purpleback flying squid Sthenoteuthis oualaniensis (Cephalopoda: Ommastrephidae) to environmental parameters using GIS and GAM in south-eastern Arabian Sea

Author

Mohamed, Kolliyil S., Sajikumar, K.K., Ragesh, Nadakkal, Ambrose, T.V., Jayasankar, J., Said Koya, K.P., and Sasikumar, Geetha

Subjects
Biodiversity, Taxonomy
Abstract

Mohamed, Kolliyil S., Sajikumar, K.K., Ragesh, Nadakkal, Ambrose, T.V., Jayasankar, J., Said Koya, K.P., Sasikumar, Geetha (2018): Relating abundance of purpleback flying squid Sthenoteuthis oualaniensis (Cephalopoda: Ommastrephidae) to environmental parameters using GIS and GAM in south-eastern Arabian Sea. Journal of Natural History 52 (29-30): 1869-1882, DOI: 10.1080/00222933.2018.1497721, URL: http://dx.doi.org/10.1080/00222933.2018.1497721

Published
2018

23. Effect of tropical monsoon on fishery abundance of Indian squid (Uroteuthis (Photololigo) duvaucelii)

Author

Sasikumar, Geetha, Mohamed, Kolliyil Sunilkumar, Mini, Kalappurakkal Gopalan, and Sajikumar, Kurichithara Kunjumani

Subjects
Biodiversity, Taxonomy
Abstract

Sasikumar, Geetha, Mohamed, Kolliyil Sunilkumar, Mini, Kalappurakkal Gopalan, Sajikumar, Kurichithara Kunjumani (2018): Effect of tropical monsoon on fishery abundance of Indian squid (Uroteuthis (Photololigo) duvaucelii). Journal of Natural History 52 (11-12): 751-766, DOI: 10.1080/00222933.2018.1447156, URL: http://dx.doi.org/10.1080/00222933.2018.1447156

Published
2018

24. Relating abundance of purpleback flying squid (Cephalopoda: Ommastrephidae) to environmental parameters using GIS and GAM in south-eastern Arabian Sea

Author

Mohamed, Kolliyil S., Sajikumar, K.K., Ragesh, Nadakkal, Ambrose, T.V., Jayasankar, J., Said Koya, K.P., and Sasikumar, Geetha

Subjects
0106 biological sciences, Squid, biology, 010604 marine biology & hydrobiology, 04 agricultural and veterinary sciences, biology.organism_classification, 01 natural sciences, Geography, Oceanography, Abundance (ecology), Distribution pattern, biology.animal, Sthenoteuthis oualaniensis, Ommastrephidae, 040102 fisheries, 0401 agriculture, forestry, and fisheries, Ecology, Evolution, Behavior and Systematics, South eastern
Abstract

The distribution pattern of purpleback flying squid and the relationship between its abundance and environmental variables in the south-eastern Arabian Sea were analysed using a geographical inform...

Published
2018
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31. Range extension of a bathypelagic squid, Bathyteuthis bacidifera (Cephalopoda: Bathyteuthidae), to the south Arabian Sea with special reference to its age and growth pattern.

Author

Sajikumar, K. K., Arkhipkin, A. I., Venkatesan, V., Jestin Joy, K. M., Binesh, C. P., Sasikumar, Geetha, and Mohamed, Kolliyil S.

Abstract

The bathypelagic squid Bathyteuthis bacidifera was collected in an open net towed at 200 m over a bottom depth range from 1200 to 2340 m in the southern Arabian Sea, near Laccadive Archipelago (09°54′32″N; 73°39′12″E, 11°16′18″N; 72°51′09″E, and 10°48′08″N; 72°41′11″ E). Morphometric and molecular analyses are presented here. This is the first record of Bathyteuthis bacidifera from the southeastern Arabian Sea and the first description of the species at the molecular level. Specimens were collected from April 2015 to January 2016 in warmer (15.2 to 15.6 °C) and shallower (∼200 m) water than previously reported. The first observations of countable increments in the statolith of the genus Bathyteuthis are reported. The statolith microstructure of the specimens (15.6 to 39.0 mm dorsal mantle length) revealed that Bathyteuthis bacidifera is a slow growing squid, with a growth rate of 0.12 to 0.20 mm/day. The record of this rare squid from the Arabian Sea is an addition to the cephalopod fauna of India and contributes to biogeographic knowledge of this unusual deep sea family. [ABSTRACT FROM AUTHOR]

Published
2018
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32. Effect of tropical monsoon on fishery abundance of Indian squid (<italic>Uroteuthis</italic> (<italic>Photololigo</italic>) <italic>duvaucelii</italic>).

Author

Sasikumar, Geetha, Mohamed, Kolliyil Sunilkumar, Mini, Kalappurakkal Gopalan, and Sajikumar, Kurichithara Kunjumani

Subjects
*SQUIDS, *OCEAN temperature, *WEATHER forecasting, *FISHERIES & climate, *TIME series analysis
Abstract

Indian squid, Uroteuthis (Photololigo) duvaucelii (Loliginidae) constitute an important component of the inshore cephalopod fisheries along the eastern Arabian Sea. Local environmental variation plays an important role in species-environment interactions in neritic squids, which inhabit nearshore/coastal waters. Such ‘active’ and ‘passive’ responses of squids to environmental changes is crucial in understanding their relationships and influence on the biological processes, distribution and abundance of the fast-growing short-lived coastal loliginids. The empirical relationship between squid abundance and the variability in rainfall and sea surface temperature (SST) were explored in a tropical monsoon fishery. Monthly catch rates (catch per fishing hour) of squids in commercial trawl during 1987-2009 were used as the abundance index. Linear regression models with ARIMA errors were fitted with catch per unit hour time series as dependent variable and rainfall and SST as exogenous variables. While rainfall was observed to have a negative effect on squid abundance, the SST recorded a positive impact. ARIMA models provided satisfactory fit to observed data and forecast of 22 months. Given that the squid life-cycle is a function of their environment, this result is relevant in forecasting squid biomass for the management of tropical monsoon fisheries. [ABSTRACT FROM AUTHOR]

Published
2018
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