Diversity of intertidal, epibiotic, and fouling barnacles (Cirripedia, Thoracica) from Gujarat, northwest India Author Trivedi, Jigneshkumar N. Department of Life Sciences, Hemchandracharya North Gujarat University, Patan- 384265, Gujarat, India Author Doshi, Mahima Department of Life Sciences, Hemchandracharya North Gujarat University, Patan- 384265, Gujarat, India Author Patel, Krupal J. Marine Biodiversity and Ecology Laboratory, Department of Zoology, The Maharaja Sayajirao University of Baroda, Vadodara- 390002, Gujarat, India Author Chan, Benny K. K. Biodiversity Research Center, Academia Sinica, Taipei 115, Taiwan text ZooKeys 2021 2021-03-25 1026 143 178 http://dx.doi.org/10.3897/zookeys.1026.60733 journal article http://dx.doi.org/10.3897/zookeys.1026.60733 1313-2970-1026-143 A27C7BA5F20646A2B307167C99BBFDDD B7D64A6A5D2952569EC76E0235617F29 Chelonibia testudinaria (Linnaeus, 1758) Figures 2H, I , 8 Examined material. Two specimens (BD 5.33 and 5.59 mm ), LFSc.ZRC-159, on carapace of crab Portunus sanguinolentus , Kuda, Bhavnagar ( 21°37.70'N , 72°18.40'E ), 17 April 2019 , Gujarat , India , sandy shore, leg. J. Trivedi. Diagnosis. Shell white, slightly conical and six-plated, radii board. Specimens living on turtles display oval-shaped depressions on radii of each shell plate. Specimens living on surfaces of decapods have a smooth outer surface, without any depressions on radii (Fig. 2I ). Aperture large, scutum and tergum reduced, elongated rectangular in shape (Fig. 2I ). Maxilla bilobed (Fig. 8A ); maxillule feebly notched, cutting edge straight (Fig. 8B ); mandible with five teeth, lower margin short (Fig. 8C-E ). Mandibulatory palp elongated with rough edges (Fig. 8F ). Labrum having cleft with numerous sharp teeth (Fig. 8G, H ). Figure 8. Chelonibia testudinaria (Linnaeus, 1758), (BD: 5.33 mm) LFSc.ZRC-159, Light Microscopy on mouth parts A maxilla B maxillule C mandible D close up on the inferior angle of mandible E close up on the teeth of mandible F mandibulatory palp G labrum H close up view on the cutting edge of labrum, showing the teeth. Scale bars in µm . Remarks. Previously, Chelonibia living on decapods were identified as C. patula and Chelonibia living on sea turtles as C. testudinaria . Cheang et al. (2013) and Zardus et al. (2014) revealed there is no significant genetic difference between C. patula and C. testudinaria , suggesting that these are the same species and their morphological differences are the result of phenotypic plasticity. We consider C. testudinaria as including two major morphs. The Chelonibia patula morph has a smooth white shell and lives mainly on decapods, while the Chelonibia testudinaria morph has oval depressions on the radii and lives mainly on surfaces of turtles. Dwarf males are often housed in these depressions on the Chelonibia testudinaria morph ( Zardus and Hadfield 2004 ; Collareta 2020 ). Worldwide distribution. Chelonibia testudinaria has been recorded in the Atlantic Ocean, Pacific Ocean and the Mediterranean Sea ( Pasternak et al. 2002 ; Rawson et al. 2003 ) including Greece ( Kitsos et al. 2003 , 2005 ), Israel ( Pasternak et al. 2002 ), Italy (Relini 1980; Frazier and Margaritoulis 1990 ), and Turkey ( Bakir et al. 2010 ). Further records included Australia ( Jones and Hosie 2016 ), Pakistan ( Javed and Mustaquim 1994 ), and India ( Krishnamoorthy 2007 ). Distribution in India. This species has been reported from Gujarat (Frazier 1990; present study), Maharashtra ( Wagh and Bal 1974 ), Kerala (Pillai 1958), Lakshadweep Islands ( Hayashi 2013 ), Tamil Nadu ( Daniel 1956 ; Krishnamoorthy 2007 ), Andhra Pradesh ( Nilsson-Cantell 1938 ), Pulicat lake ( Daniel 1981 ), Odisha (formerly Orissa) ( Nilsson-Cantell 1938 ), west Bengal ( Daniel 1981 ), and Andaman and Nicobar Islands ( Nilsson-Cantell 1938 ).