Pachyseris inattesa sp. n. (Cnidaria, Anthozoa, Scleractinia): a new reef coral species from the Red Sea and its phylogenetic relationships Author Terraneo, Tullia I. Author Berumen, Michael L. Author Arrigoni, Roberto Author Waheed, Zarinah Author Bouwmeester, Jessica Author Caragnano, Annalisa Author Stefani, Fabrizio Author Benzoni, Francesca text ZooKeys 2014 433 1 30 http://dx.doi.org/10.3897/zookeys.433.8036 journal article http://dx.doi.org/10.3897/zookeys.433.8036 1313-2970-433-1 CA51CB5E3FAD4179BA0BDFE924989773 Taxon classification Animalia Scleractinia Agariciidae Pachyseris rugosa (Lamarck, 1801) Figures 1 a-c , 2 Pachyseris rugosa For synonymy, see Scheer and Pillai (1983) . Material examined. BMRI 62, Semporna, Malaysia (MV Celebes, Explorer, SMEE), 04°34'01.8"N , 118°45'27.5"E , 11 December 2010, coll. Z. Waheed; IRD HS2856, Prony Bay, New Caledonia, 22°21.230'S , 166°49.300'E , 10 m, 23 February 2011, coll. F. Benzoni; IRD HS2893, Prony Bay, New Caledonia, 22°21.230'S , 166°49.300'E , 10 m, 22 February 2011, coll. F. Benzoni; IRD HS3383, Mare , Loyalty Islands, New Caledonia (MV Alis, BIBELOT), 16 February 2014, coll. F. Benzoni. Corallum : Highly variable in shape from encrusting with foliose margins and central knobs ( Veron and Pichon 1980 ) to caespitose with bifacial fronds of variable width growing upward (Figures 1 a-c , 2 a-b ). Fronds can be anastomose ( Veron and Pichon 1980 ). The corallum surface is undulated or corrugated due to the presence of well-developed carinae ( Veron and Pichon 1980 ). Figure 1. Colonies of Pachyseris rugosa ( a-c ) and Pachyseris speciosa ( d-g ) in situ. a Image of the whole colony of specimen IRD HS2893, Prony Bay, New Caledonia b Lateral view of the fronds of specimen IRD HS2594, Prony Bay, New Caledonia c Fronds of specimen IRD HS2856 viewed from above, Prony Bay, New Caledonia d Tiers of foliose projections of a colony from New Caledonia e Image of specimen UNIMIB SO040, Socotra Island f Part of specimen KAUST SA714, Saudi Arabia g Detail of a colony with reduced carinae and brightly colored polyp mouths, growing in very turbid environment, Banc des Japonais, New Caledonia. Figure 2. Pachyseris rugosa . a Lateral view of colony IRD HS1442 b Lateral view of colony IRD HS152 showing very irregular fronds and carinae c Detail of the fronds of specimen IRD HS152 d Specimen IRD HS221, white arrow points at a dash-like columella e SEM image of IRD HS2594, white arrows point at the fused dissepiments connecting the inner end of the radial elements and the reduced columellae f SEM image of ornamentation on radial elements showing single granules (sg), clumped granules (cg) and menianae (me). Calices: Arranged in rows, mostly indistinct. Rows can be long and continuous, or short and irregular, especially on the fronds (Figures 2 a-d ). Series of calices are generally arranged parallel to each other and are concentric in the encrusting or foliose parts of the corallum. Series are separated by carinae with variable vertical development and inclination with respect to the corallum surface (Figures 2 b-c ). At the base of the fronds, the carinae can be very short and resemble hydnophoroid protuberances (Figure 1c). Columella: Well-developed, made by a dash-like process rising from a horizontal fig made of dissepiments from the inner ends of the radial elements (Figure 2d; Veron and Pichon 1980 : fig. 137). In the terminal parts of the corallum, especially on the top of the fronds, dash-like processes can be reduced to low-lying ridges mostly continuous between centres and the structure made by the fused dissepiments is more clearly visible (Figure 2e). Radial elements: Radial elements are continuous across the carinae, regularly spaced and equal or slightly alternating (Figures 2 c-e ). Lateral faces bear regularly distributed, parallel lines of granules or/and ledge-like features called menianae ( Benzoni et al. 2012 , Kitahara et al. 2012a ) often alternating along the same radial element. Such lateral ornamentation is variable and includes single granules, groups of 2-4 clumped granules and menianae with minutely beaded edges (Figure 2f). All lateral ornamentations are oriented in lines parallel to the upper radial element margin. The upper margin of the radial element is minutely beaded and straight in the portions above the menianae and typically attains a zigzag pattern with variable angles in the portions where single or clumped granules are present (Figure 2f).