Decapoda - Brachyura - Epialtidae - Tylocarcinus
| Tylocarcinus styx (Herbst, 1803) |
World Distribution
Sakai (2004 - CD) - Indo-West Pacific. Red Sea to Fiji. This include, Seychelles, Réunion, Maurice, Chagos, Andaman, Taiwan, Japan, Philippines, New Caledonia. Plus French Polynesia (Society).
Sakai (2004 - CD) - Indo-ouest Pacifique. Mer Rouge aux Fidji. Comprend, Seychelles, Réunion, Maurice, Chagos, Iles Andaman, Taiwan, Japon, Philippines, Nouvelle-Calédonie. Europa, Juan de Nova.
Environnement : Marine - Substrat/Association : Hard bottom (rock and rubbles)
Vertical range : Shallow-waters (0-100 m) - Min-Max observed: 0-17 m
Mayotte data
Tylocarcinus styx (Herbst, 1803)
Material examined — Mayotte KUW 2009, st. 12, reef La Prévoyante, 6-11 m, 1 M juv. 4.9 x 2.3 mm, photo, MNHN B32534, MNHN-IU-2009-1294; st. 14, Prudente Bank, 15-17 m, 1 M 8.15 x 4.4 mm (horns broken), 3 MM with sacculina 10.2 x 4.9 to 13.5 x 7.0 mm, 2 MM juv. 8.4 x 4.1 and 8.4 x 4.5 mm, 1 F juv. 7.2 x 3.6 mm MNHN B32533, MNHN-IU-2009-1293; st. 26, Mutsumbatsou reef flat, intertidal low tide, 1 F 11.3 x 5.9 mm, photo MNHN B32531, MNHN-IU-2009-1291, 1 M 13.2 x 7.1 mm, 1 F 10.8 x 5.7 mm, MNHN B32532, MNHN-IU-2009-1292.
Others records — Poupin et al., 2013c: 11, Glorieuses, Expedition Glorieuses December 2012 (new record), st. Dive 12; also aff. Tylocarcinus styx (Herbst, 1803) - Expedition Glorieuses December 2012 (new record), st. BIO 37, 0.9 m, Island du Lys, 1 M 11.1 (with horns) x 4.9 mm. - Poupin, 2016: 50, Juan de Nova, Expedition Juan de Nova December 2013, reef-block, 1 male 19.5x13.9 mm, st. 10 (photo) (nr), 1 male st. 17 (MNHN). - BIOTAS 2009, Juan de Nova, st. JDN06, lots MEPA-00393.
Remarks — Male pleopod of this species is figured by Guinot (1962c: 240, fig. 17a, b) with a characteristic triangular distal lobe. Tylocarcinus styx is rather polymorphic, for example for extension of basal fused part of horns, and has variable shades of green, red, brown or pink in live coloration. A character rather constant and useful to quickly recognized this crab on the reef is the skull-shaped design present on posterior carapace.
Geographic and depth ranges — IWP, Red Sea, Mayotte (this work) to Japan, French Polynesia; intertidal to subtidal
Europa data
Tylocarcinus styx. - Lenz (1910: 542, 1 mâle, 1 femelle du récif corallien de l'île Europa). - Europa, BIOTAS collections, specimen MEPA-00262, st EURO-11, MEPA-00264, st. EURO-18, dét. J. Poupin d'après photos. - Mission BIORECIE, St. 8, 1 male 10.3 (without horns)x6.1 mm (MNHN), 1 female 13.6(without horns)x9.6 mm (MNHN).
Réunion data
Arctopsis styx - A. Milne-Edwards, 1862, annexe F : 6 (Réunion, coll. Maillard). - Tylocarcinus styx - Ribes, 1978 (Réunion). - Mission Poupin, avril 2008 (D'après photographies du programme BIOTAS). - Réunion - Program BIOLAVE, ARVAM, J.-P. Quod, photo, plate A. Barrère.
New Caledonia data
Nouvelle Caledonie, STATION — Edwards AM, Nouv Arch MNHN 8: 229-267
Central Pacific data (Wallis & Futuna, Polynesia, Clipperton, Easter Island)
Tylocarcinus styx - Unpublished specimens, coll. & det. G. Paulay, Rangiroa, October 10, 2001 (FLMNH-UF 1638), also (FLMNH-UF 1528, 1535, 1570, 1590, 1598, 1654). (first record for FP); Austral, Neilson reef, coll. BENTHAUS Expedition, stn DW1917, dredge 50-60 m, prov. det. J. Poupin from photograph. - Moorea Biocode project (with a '?'). - Remark - This record, initially mentioned under Tiarinia cornigera (Latreille, 1825), was corrected into Tylocarcinus styx in February 2009, based on redetermination by G. Paulay. - Salvat & Bacchet, 2011: 246, photo, field guide 'Au Vent des Iles Ed. Tahiti - French Polynesia, most often Society (Moorea, Tahiti).
References : PDF list, 214 pp (1.4 Mo)This species in Worms Database