BIODIVERSITAS ISSN: 1412-033X Volume 20, Number 1, January 2019 E-ISSN: 2085-4722 Pages: 85-90 DOI: 10.13057/biodiv/d200111 Short Communication: Age and growth of elongated mudskipper, Pseudapocryptes elongatus (Cuvier, 1816) from Sundarbans, India GOPALAN MAHADEVAN 1, ♥ , PALANIVEL BHARATHIRAJAN 1 , VELAYUTHAM RAVI 1 , MOJTABA POULADI 2 , MARYAM MIRZAEI VAND KHANGHAH 2 1 Centre of Advanced Study in Marine Biology, Faculty of Marine Sciences, Annamalai University. Parangipettai-608 502, Tamil Nadu, India, Tel.: +91-8870214112, ♥ email: marinemahadevan@gmail.com 2 Department of Fisheries, Faculty of Fisheries and Environmental Sciences, Gorgan University of Agricultural Sciences and Natural Resources. Gorgan, Golestan, Iran Manuscript received: 8 November 2018. Revision accepted: 2 December 2018. Abstract. Mahadevan G, Bharathirajan P, Ravi V, Pouladi M, Mirzaei Vand Khanghah M. 2019. Short Communication: Age and growth of elongated mudskipper, Pseudapocryptes elongatus (Cuvier, 1816) from Sundarbans, India. Biodiversitas 20: 85-90. The estimation of age and mathematical expression of fish growth is complex and debated subject in fishery sciences. Growth parameters of elongated mudskipper, Pseudapocryptes elongatus were estimated based on the length frequency data using FiSAT II software (several tools such as Powell-Wetherall method, ELEFAN and von Bertalanffy growth estimates). Samples were collected from Sundarbans mangroves using gill and cast nets and by hand picking. The length-frequency (LFQ) of P.elongatus was recorded from January 2014 to December 2015 and the above tools estimated the growth parameters (L∞, K and t0) from the progression of LFQ modes through time. L∞ and K values of males were 220.50 mm and 1.3 yr -1 , respectively and similarly, L∞ and K values of females were 221.05 mm and 1.21 yr -1 , respectively. The t0 values estimated for males and females were-0.1915 years and-0.1661 years, respectively. The estimated growth performance index (Φ) values for males and females of P. elongatus were 4.394 and 4.503, respectively. The lifespan of both the sexes was found to be 4 + years. Keywords: Age and growth, Pseudapocryptes elongatus, FiSAT II, Sundarbans, India INTRODUCTION The Gobiidae is not only the largest family of the order Perciformes but also the species-rich family in fishes and also among vertebrates (Van Tassell 1998). The total number of genera is about 212 with roughly 1875 species. The five provisionally recognised subfamilies are Oxudercinae (Murdy, 1989), Amblyopinae (Hoese 1984; Birdsong et al. 1988) Sicydiinae (Pezlod 1993), Gobionellinae (Pezlod 1993) and Gobinnae (Birdsong et al. 1988; Pezlod 1993). The estimation of age and mathematical expression of fish growth is complex and debated subject in fishery sciences. Controversy still rages around the most appropriate means of age determination (Nedreaas 1990). Information on the age and growth of an organism is extremely important in understanding the nature of its stock, the role played by various year classes in the fishery constituted by the animal, the conditions required for optimum growth, the influence of environmental factors on growth, and also in comparing the rate of growth in different water bodies (Katselis et al. 2002). The analysis of length-frequency data is a reliable way of obtaining age and growth parameters of fishes in a tropical region. Many computer-assisted methods exist for the analysis of length-frequency data of fish and shell fish such as LFSA (Sparre and Venema 1987), COMPLEAT ELEFAN (Gayanilo et al. 1988), MULTIFAN (Fournier et al. 1990), FiSAT (Gayanilo and Pauly 1997) and LFDA (Kirkwood et al. 2001). Each method has its own strengths and inadequacies. The ELEFAN method is the most broadly used because it is easy to use, its utilization requests small preparing force, it doesn't require ordinariness in the appropriation of the informational collection utilized and the hypothesis behind it is straightforward. Previously very few attempts were made to determine the age and growth of P. elongatus. Zhang et al. (1990) studied the age and growth of Boleophthalmus pectinirostris collected from the tidal mudflats of China. Washio et al. (1990) determined the age and growth of B. pectinirostris collected from the Midori River Japan. King (1995) predicted the population dynamics of the mudskipper P. barbarus from the Gross River estuary of Nigeria. P. elongatus is commonly called as elongate mudskipper and they are an important estuarine fish of east coast of India. Cai (1996) studied the population structure and reproductive biology of B. pectinirostris in Shenzhen bay located in China. Dinh et al. (2007) studied the biological aspects of P. lanceolatus distributed along the coastal areas of the Mekong Delta in Vietnam. Bucholtz et al. (2009) evaluated length-weight of the mudskipper P. elongatus in the Mekong Delta, Vietnam. So far no attempt was made to determine the age and growth of the