Rhyssoplax affinis ( Issel, 1869 )

Dell’Angelo, Bruno, Landau, Bernard M., Sosso, Maurizio & Taviani, Marco, 2020, Late Pleistocene Red Sea Mollusca: 1. Polyplacophora, Zootaxa 4772 (3), pp. 401-449 : 412-414

publication ID

https://doi.org/ 10.11646/zootaxa.4772.3.1

publication LSID

lsid:zoobank.org:pub:F546A223-59A0-4DA1-9102-AD7BC482105F

DOI

https://doi.org/10.5281/zenodo.3844069

persistent identifier

https://treatment.plazi.org/id/03D21D39-FFB9-3954-FF7B-FA2FFA8BDF40

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Plazi (2020-05-11 05:40:28, last updated 2024-11-24 23:28:18)

scientific name

Rhyssoplax affinis ( Issel, 1869 )
status

 

Rhyssoplax affinis ( Issel, 1869) View in CoL

( Fig. 7 View FIGURE 7 )

Chiton affinis Issel 1869, p. 234 View in CoL ; Sykes 1907, p. 34; Pallary 1926, p. 30, pl. 4, figs 8–9 (ex Savigny 1817: pl. 3, figs 8–9); Moazzo 1939, p. 217; Yaron 1973, p. 15; Bouchet & Danrigal 1982, p. 11, fig. 51; Dekker & Orlin 2000, p. 7; Abubakr 2004, p. 73; Dekker & Gemert 2008, p. 124.

Chiton (Clathropleura) affinis View in CoL ; Thiele 1909, p. 91, pl. 9, figs 41–44.

Chiton olivaceus Spengler var. affinis View in CoL ; Leloup, 1952, p. 27, text-fig. 11, pl. 4, fig. 4; Leloup 1960, p. 36; Vine 1986, p. 125, unnumbered fig. p. 125.

Rhyssoplax affinis ; Ferreira 1983, p. 268, figs 22, 24; Blatterer 2019, p. 52, pl. 3, fig. 7 a–s.

Chiton (Rhyssoplax) affinis View in CoL ; Kaas & Van Belle 1988, p. 122, figs 34–40; Van Belle & Wranik 1991, p. 372, fig. 18; Van Belle 1994, p. 6; Bosch et a l. 1995, p. 190, fig. sp. 884; Kaas 1996, p. 371; Schwabe 1997, p. 26, unnumbered figs at p. 27; Kaas & Van Belle 1998, p. 14; Anseeuw & Terryn 2004, p. 11, figs 5, 42–43; Kaas et al. 2006, p. 165, fig. 61, map 30; Di Napoli & Janssen 2009, p. 15, pl. 8a–d; Schwabe 2010, figs 1A, 2A, 5A–B; Mohammadian 2011, p. 211.

Type material. Lectotype MNHN in Savigny Collection, designated by Ferreira (1983: 268), as illustrated in Bouchet & Danrigal (1982: fig. 51).

Type locality. Gulf of Suez.

Material examined. Jordan, Aqaba (Yamanie) (St. 1): 2 intermediate valves ( MZB 50592). Saudi Arabia, Gulf of Aqaba (Ash Shaykh Humayd): St. 2: 1 intermediate valve ( MZB 50593); St. 7: 1 intermediate valve ( MZB 50594); St. 8: 10 intermediate valves ( MZB 50595); St. 9: 6 valves (1 head, 4 intermediate and 1 tail) ( MZB 50596). Egypt (Hurghada): St. 13: 48 valves (3 head, 36 intermediate and 9 tail), Figs 7 View FIGURE 7 G–I ( BD 187; MZB 50531); St. 14: 106 valves (10 head, 90 intermediate and 6 tail), Figs 7 View FIGURE 7 A–F ( BD 188; MZB 50530); RGM.1356852); St. 14bis: 4 valves (3 intermediate and 1 tail) ( BD 189); St. 15: 3 valves (2 intermediate and 1 tail) ( BD 190); St. 16: 59 valves (12 head, 36 intermediate and 11 tail) ( BD 191). Maximum width: 4 / 7.1 / 4 mm.

Description. Head valve semi-circular, posterior margin widely V-shaped, front slope slightly convex, tegmentum sculptured with 13–14 strong radial ribs, some bifurcating, interstices pitted.

Intermediate valve rectangular, L/W = 0.34–0.42, front margin sinuous, moderately to highly elevated (H/W = 0.42–0.47), anterior profile carinated, side margins short, weakly bilobed, posterior margin straight at both sides of well defined apex, lateral areas clearly defined, sculptured like head valve, 2 radial ribs separated by pitted interstices, pleural areas with ca 10 longitudinal, slightly forwardly converging grooves, innermost not reaching anterior margin of valve, interspaces somewhat broader, smooth, jugal area narrow, smooth.

Tail valve semi-circular, length more than half the width (L/W = 0.58–0.60), front margin slightly convex, posterior margin lobate, mucro well defined, subcentral, prominent, antemucronal slope almost straight or slightly convex, postmucronal slope slightly convex, antemucronal area sculptured like central area of intermediate valve, postmucronal area with sculpture like head valve.

Articulamentum with apophyses wide, short, connected across the shallow sinus by short, denticulated jugal plate, insertion plates short, slit formula 8/1/10–13, teeth inequidistant, irregular, finely striated on the upper side, slit rays not indicated.

Remarks. Issel´s original description (1869) has subsequently been revised by several authors ( Leloup 1952; Ferreira 1983; Kaas et al. 2006). Rhyssoplax affinis has been confused with the Mediterranean R. olivaceus ( Spengler, 1797) by authors following Cooke (1885). The controversy, summarized by Leloup (1952), was resolved by Yaron (1973), who demonstrated consistent morphological differences between the two species. This is the first report of this species as a fossil.

Distribution. Late Pleistocene: Jordan, Aqaba (Yamanie); Saudi Arabia, Gulf of Aqaba (Ash Shaykh Humayd); Egypt (Hurghada: this study). Present-day: Indian Ocean: Red Sea, Gulf of Suez, Yemen, Socotra Island, Gulf of Oman, the Arabian Gulf, Seychelles and Somalia ( Kaas et al. 2006; Di Napoli & Janssen 2009; Blatterer 2019).

Abubakr, M. M. (2004) The Republic of Yemen Marine Biotic Ecosystem (Resources-Habitats and Species). Ministry of Water and Environment, Environment Protection Authority, Aden, 128 pp.

Anseeuw, B. & Terryn, Y. (2004) Intertidal chitons (Mollusca: Polyplacophora) from the coast of Jordan, Red Sea, with the description of a new species of Parachiton Thiele, 1909. Bollettino Malacologico, Supplement 5, 1 - 24.

Blatterer, H. (2019) Mollusca of the Dahab region. Oberosterreichisches Landesmuseum, Linz, Austria, 480 pp.

Bouchet, P. & Danrigal, F. (1982) Napoleon's Egyptian Campaign (1798 - 1801) and the Savigny Collection of Shells. The Nautilus, 96, 9 - 24.

Cooke, A. H. (1885) Report on the Testaceous Mollusca obtained during a dredging excursion in the Gulf of Suez in the months of February and March 1869. Annals and Magazine of Natural History, 16, 262 - 276. https: // doi. org / 10.1080 / 00222938509459881

Dekker, H. & Orlin, Z. (2000) Check-list of Red Sea Mollusca. Spirula, 47 (Supplement), 1 - 46.

Dekker, H. & Gemert, L. J. van (2008) A new list with corrections to the shells pictured in Red Sea Shells (1984) by Doreen Sharabati. De Kreukel, 44, 123 - 136.

Ferreira, A. J. (1983) Researches on the coast of Somalia. The chiton fauna (Mollusca Polyplacophora). Monitore Zoologico Italiano, 9, 249 - 297. https: // doi. org / 10.1080 / 00269786.1983.11758574

Issel, A. (1869) Malacologia del Mar Rosso. Ricerche zoologiche e paleontologiche. Parte terza. Catalogo delle conchiglie fossili raccolte sulle spiagge emerse del Mar Rosso. Biblioteca Malacologica, Pisa, 61 pp. [pp. 243 - 303]

Kaas, P. & Van Belle, R. A. (1988) Chitons (Mollusca: Polyplacophora) from the coasts of Oman and the Arabian Gulf. American Malacological Bulletin, 6, 115 - 130.

Kaas, P. (1996) Chitons (Mollusca: Polyplacophora) from the Seychelles with description of a new species. Zoologische Mededelingen, 70, 367 - 375, figs. 1 - 11.

Kaas, P. & Van Belle, R. A. (1998) Catalogue of living chitons (Mollusca, Polyplacophora). Second, revised edition. Backuys Publishers, Leiden, 204 pp.

Kaas, P., Van Belle, R. A. & Strack, H. L. (2006) Monograph of Living Chitons (Mollusca: Polyplacophora). Volume 6. Suborder Ischnochitonina (concluded): Schizochitonidae; Chitonidae. Additions to Volumes 1 - 5. E. J. Brill, Leiden-Boston, 463 pp.

Leloup, E. (1952) Polyplacophores de l'Ocean Indien et des cotes de l'Indochine francaise. Institut Royale des Sciences Naturelles de Belgique, Memoires, Series 2, 7, 1 - 69, 6 pls.

Leloup, E. (1960) Amphineures du golfe d'Aqaba et de la Peninsule Sinai. Sea Fisheries Research Station, Haifa, Bulletin, 29, 29 - 55, pl. 1.

Moazzo, P. G. (1939) Mollusques testaces marins du Canal de Suez. Memoires de l'Institut d'Egypte, 38, 1 - 287.

Mohammadian, H. (2011) The molluscs in Iran. Shabpareh Publishing Company, Tehran, 229 pp. [in Arabic script]

Pallary, P. (1926) Explication des planches de J. C. Savigny. Memoires de l'Institut d'Egypte, 11, i-viii + 1 - 139, pls. 1 - 18.

Savigny, J. C. (1817) Description de l'Egypte, ou recueil des observations et des recherches qui ont ete faites en Egypte pendant l'Expedition de l'armee francaise, publiee par ordre du gouvernement. Histoire naturelle. Planches. Vol. II. Imprimerie royale, Paris, IV + 69 + 36 + 24 + 16 + 20 + 44 + 79 + 51 + 26 + 4 + 18 + 18 + 98 + 22 + 24 + 12 + 95 + 63 + 12 + 2 pp.

Schwabe, E. (1997) Beitrag zur Kenntnis einiger Kaferschnecken (Polyplacophora) des Roten Meeres. Club Conchylia Informationen, 29, 25 - 30.

Schwabe, E. (2010) Illustrated summary of chiton terminology. Spixiana, 33, 171 - 194.

Spengler, L. (1797) Udforlig beskrivelse over det mangeskallede konkylie-slaegt, af Linnaeus kaldet Chiton; met endeel nye Arter og Varieteter. Skrivter af Naturhistorie Selskabet, 4, 62 - 103, pl. 6.

Sykes, E. R. (1907) Reports on the marine biology of the Sudanese Red Sea. 5. On the Polyplacophora or chitons. Journal of the Linnean Society of London, 31, 31 - 34. https: // doi. org / 10.1111 / j. 1096 - 3642.1907. tb 00450. x

Thiele, J. (1909) Revision des Systems der Chitonen. Zoologica, 22, 1 - 132, pls. 1 - 10. https: // doi. org / 10.5962 / bhl. title. 11245

Van Belle, R. A. & Wranik, W. (1991) Chitons (Mollusca: Polyplacophora) from the Coasts of Yemen and Socotra Island. Fauna of Saudi Arabia, 12, 366 - 381.

Van Belle, R. A. (1994) On the chiton fauna of Bahrain, Arabian Gulf. Gloria Maris, 33, 1 - 6.

Vine, P. (1986) Red Sea Invertebrates. IMMEL Publishing, London, 224 pp.

Yaron, I. (1973) A note on the taxonomic status of Chiton affinis Issel. Argamon, 4, 15 - 17.

Gallery Image

FIGURE 7. Rhyssoplax affinis (Issel, 1869). A–I. Egypt, Hurghada, Late Pleistocene (last interglacial MIS5e). A–C. MZB 50530a, head valve (St. 14), width 3.6 mm, dorsal, ventral and lateral views. D–F. MZB 50530b, intermediate valve (St. 14), width 5.7 mm, dorsal, ventral and frontal views. G–I. MZB 50531, tail valve (St. 13), width 2.5 mm, dorsal, ventral and lateral views.

MZB

Museum Zoologicum Bogoriense

RGM

National Museum of Natural History, Naturalis

Kingdom

Animalia

Phylum

Mollusca

Class

Polyplacophora

SubClass

Loricata

Order

Chitonida

SubOrder

Chitonina

SuperFamily

Chitonoidea

Family

Chitonidae

SubFamily

Chitoninae

Genus

Rhyssoplax