Diversity of Sponges in Marine Protected Areas of North Andaman, India Preeti Pereira 1 & Chelladurai Raghunathan 1,2 # Springer International Publishing AG, part of Springer Nature 2018 Abstract The continental shelf of the Andaman and Nicobar Islands harbours rich sponge diversity. Despite being one of the most important components of the reef ecosystem, comprehensive inventories of marine sponges of the protected areas of these Islands are still lacking. The present study was devoted to provide an outline of the sponge species composition of the island sanctuaries and adjoining areas of North Andaman and to compare the species assemblage from east and west coasts. The intertidal and subtidal sponges were surveyed from 41 sites covered under 23 locations (17 island sanctuaries and 6 undesignated locations) during March 2016 – September 2017. A total of 43 sponges distributed among 16 orders, 25 families and 35 genera were identified and recorded. The number of sponges per location was ranging from 6 to 20 in the east coast with a mean (mean ± SE) of 14± 2.07 and 3 to 21 in the west coast with a mean of 9.13±1.44, indicating a significant difference on a spatial scale, notwithstanding the geographical proximity of the survey locations. Haplosclerida was the most represented order (9 species), contributing approximately 21% to the total sponge biodiversity, followed by Axinellida and Dictyoceratida (6 species). Two species namely, Carteriospongia foliascens (18 locations) followed by Neopetrosia exigua (16 locations) were dominant from the survey locations, indicating their ubiquitous occurrences throughout the survey locations. Sixteen growth forms were observed of which, cushions were the most dominant growth form (18.6%) followed by thin sheets (16.28%) and massive- globose (11.63%), suggestive of their survival ability in the coral-reef environments. Nevertheless, the significant differences in the species composition and growth forms among the survey locations are likely to be attributed to numerous ecological and environmental factors. Further research on sponges should be devoted in understanding their interaction with other fauna. Keywords Andaman and Nicobar Islands . Distribution . Diversity . Porifera Introduction The continental shelf of the Andaman and Nicobar Islands har- bours rich sponge (Phylum Porifera) diversity. Taxonomic stud- ies on sponges in these Islands date back to 1902 when Schulze (1902) provided an account of the deepwater sponges collected by R.I.M.S. Investigator (1884–1900). Since then, studies on sponges have been very sporadic and scanty. Annandale (Annandale 1915) provided an account of few parasitic sponges. Subsequent literature reports on sponges (Burton 1928; Burton and Rao 1932; Dendy and Burton 1926) were mainly based on the rich collections of R.I.M.S. Investigator. Pattanayak (Pattanayak 2006) studied the extant specimens maintained at the Zoological Survey of India (Kolkata) and listed a total of 75 sponges from these Islands. Though the taxonomic and bio- diversity studies of marine sponges in the Islands has significant- ly increased in the last decade, most of the recent studies (Immanuel and Raghunathan 2011; Immanuel et al. 2015a, b; Ubare and Mohan 2016) are restricted only to South Andaman. More recently, (Raghunathan et al. 2017) have provided detailed descriptions of 41 sponge species from these Islands. However, knowledge of the sponge species composition is far from com- plete and comprehensive inventories in other islands are still lacking. Implementation of spatial management tools such as Marine Protected Areas and Sanctuaries are a common prac- tice in biodiversity conservation and management (Guidetti et al. 2014). However, the knowledge of the marine fauna inhabiting an area and their interactions with other areas are * Preeti Pereira preeti0018@yahoo.co.in Chelladurai Raghunathan raghuksc@rediffmail.com 1 Andaman and Nicobar Regional Centre, Zoological Survey of India, Haddo, Port Blair, Andaman and Nicobar Islands 744102, India 2 Zoological Survey of India, M – Block, New Alipore, Kolkata, West Bengal 700053, India Thalassas: An International Journal of Marine Sciences https://doi.org/10.1007/s41208-018-0073-2