Search

Morphological parameters comprising length-weight relationships (LWRs), sex ratio, condition factor (KF) and allometric growth of paradise threadfin, Polynemus paradiseus from the southern coast of Bangladesh were estimated. A total of 221 specimens were collected with the help of local fishermen ranging size 8.30-13.70 cm standard length (SL) and 11.64-50.67 g body weight (BW) during the period of January to October, 2104. The overall sex ratio of the samples did not reveal significant variation from the expected value of 1:1 (male: female=1:0.99, χ2=0.004, P < 0.05). Length-frequency distribution revealed a size predominance of males over females, where mean variation of males consistently exceeded that of females throughout the year. The allometric coefficient b of LWR significantly deviated from 3 indicating allometric growth in males and females. The analysis of covariance (ANCOVA) showed significant differences in slope and intercept between the sexes (P < 0.001). KF by month in both sexes indicating the fishes were thriving very well in the coast of Bangladesh. This study reports the first findings regarding the LWRs, sex ratio and KF of Polynemus paradiseus in the coastal waters of Bangladesh

A taxonomic review of seven-spined Polynemus species recognizes two species as valid: P. hornadayi Myers, 1936, currently known only from western Sarawak, Kalimantan, Malaysia, and P. paradiseus Linnaeus, 1758, distributed from India to Thailand and regarded as a senior synonym of P. aureus Hamilton, 1822, P. longifilis Cuvier in Cuvier and Valenciennes, 1829, P. risua Hamilton, 1822, and P. toposui Hamilton, 1822. Polynemus hornadayi differs from P. paradiseus in having a strongly protruded occipital profile (vs. nearly straight in the latter), lower counts of anal fin soft rays (mode 11 vs. 12) and gill rakers (26 vs. 32 or 33), higher counts of pectoral fin rays (18 vs. 17), scales above and below the lateral line (11 and 18 vs. 7 and 11, respectively), and pored lateral line scales (94 vs. 70), the fifth pectoral filament longest (vs. sixth), the fourth pectoral filament longer (extending well beyond the posterior central margin of the caudal fin vs. not reaching posterior central margin), a longer pectoral fin ray (posterior tip of pectoral fin reaching to midpoint of anal fin base vs. not reaching), a deeper maxilla posterior margin (mean 5% of SL vs. 4% of SL), and a well-developed swimbladder (vs. absent).

Ten fresh fish samples of different species (Mugil cephalus, Setipinna phasa, Coilia dussumieri, Scatophagus argus, Sillanopsis panijus, Arius caelatus, Hilsa ilisha, Polynemus paradiseus, Platicephalus indicus and Pelamys chiliensis) collected from Kuakata, Bangladesh were assessed biochemically (proximate composition, total volatile basic nitrogen, tri-methyl amine and pH). Moisture content of fresh fish varied over a range from 65.33 to 78.92%. Likewise, protein (8.58 to 19.06%), fat (6.12 to 12.99%) and ash (1.07 to 8.41%) content indicated wide variation in the ten fresh fish analysed. TVB-N and TMA-N values of fresh fish were found ranging between 10.92±0.23 to 25.75±0.80 mg N 100 g G and 7.70±0.67 to 18.50±0.77, respectively. The 1 values of pH of the samples ranged from 7.03±0.05 to 6.7±0.07.

The generic name Parapolynemus is proposed for the polynemid fish originally identified as Polynemus verekeri Saville-Kent. An osteological examination of the species of Polynemus Linnaeus revealed striking and unique characters in Polynemus verekeri Saville-Kent. Parapolynemus verekeri is redescribed. This is the smallest species in Polynemidae. Polynemus intermedius Nichols is a junior synonym of P. verekeri. Parapolynemus verekeri occurs along part of the north coast of Australia and south coast of New Guinea. IN his genus Polynemus, Linnaeus (1758) named three divergent species that are today recognized as Polynemus paradiseus, Pentanemus quinquarius, and Polydactylus virginicus. Feltes (1991) noted that there are two major lineages in the Polynemidae. Polynemus is representative of those polynemids that have a marked reduction in the size of the orbit, with a corresponding modification of the associated bones, and insertion of the pectoral fin relatively high on the body. The species previously recognized as Polynemus verekeri Saville-Kent shares these characters; however, based on a suite of conspicuous differences, it is placed in a new genus, Parapolynemus. The species of Polynemus occur from the Ganges Delta to Borneo, whereas Parapolynemus verekeri has been taken in Australia from the Cambridge Gulf in northern Western Australia to Arnhem Land, Northern Terri

A taxonomic review of seven-spined Polynemus species recognizes two species as valid:P. hornadayi Myers, 1936, currently known only from western Sarawak, Kalimantan, Malaysia, and P.paradiseus Linnaeus, 1758, distributed from India to Thailand and regarded as a senior synonym of P.aureus Hamilton, 1822, P. longifilis Cuvier in Cuvier and Valenciennes, 1829, P. risua Hamilton, 1822,and P. toposui Hamilton, 1822. Polynemus hornadayi differs from P. paradiseus in having a stronglyprotruded occipital profile (vs. nearly straight in the latter), lower counts of anal fin soft rays (mode 11vs. 12) and gill rakers (26 vs. 32 or 33), higher counts of pectoral fin rays (18 vs. 17), scales above andbelow the lateral line (11 and 18 vs. 7 and 11, respectively), and pored lateral line scales (94 vs. 70), thefifth pectoral filament longest (vs. sixth), the fourth pectoral filament longer (extending well beyond theposterior central margin of the caudal fin vs. not reaching posterior central margin), a longer pectoralfin ray (posterior tip of pectoral fin reaching to midpoint of anal fin base vs. not reaching), a deepermaxilla posterior margin (mean 5% of SL vs. 4% of SL), and a well-developed swimbladder (vs.absent).

Polynemus paradiseus [spec. nov.] P. digitis septem, cauda bifida. Edw. av. 208. t. 208. Paradisea piscis. Habitat in India. Genus a Trigla distinctum pinnis ventralibus, non in pectore, sed abdomine sitis; nec digiti articulati, ut in Triglis., Published as part of Linnaeus, Carolus, 1758, Systema Naturae per regna tria naturae: secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis, Stockholm :Laurentius Salvius on page 317, DOI: 10.5962/bhl.title.542, http://zenodo.org/record/3922206