New Cones from Oman and the Status of Conus Boschi (Gastropoda; Conidae) *
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MOOLENBEEK & COOMANS New Cones from Oman APEX 8(1-2) 19-26, mars 1993 New Cones from Oman and the status of Conus boschi (Gastropoda; Conidae) * R G MOOLENBEEK and H E COOMANS Zoologisch Museum Amsterdam, P O Box 4766, NL-1009 AT Amsterdam, The Netherlands ABSTRACT Conus boschorum and C biraghii omanemis are descnbed as new to science As far as we know both have a limited distnbution (Masirah island and Hallaniyah Islands [=Kuna Muna Islands]) After studying additional matenal of C boschi Clover, 1972, it must be considered a jumor synonym of C melvilh Sowerby III, 1879 KEYWORDS Gastropoda, Conidae, Conus, Oman, nomenclature INTRODUCTION MOOLENBEEK, 1990) we had no idea to which For over a century the Arabian Peninsula Conus species these "juvemles" should be has been a major and mystical source of assigned conchological treasures In recent years In November 1991 the first author joined knowledge of the molluscs of the Sultanate of an expedition, mitiated by Dr Bosch, to obtam Oman has increased after the publication of more matenal and new data concerning the "Seashells of Oman" by Donald and Eloise malacofauna fi'om the Oman coast Dunng a BOSCH (1982) They discovered the special week of intensive collectmg on Masirah Island, malacological nchness of Masirah Island, we discovered the habitat of these "juvenile" which IS situated in the Arabian Sea, just off cones They live subtidally m a bottom the coast of Oman This island has been visited community with algae, sponges, and other by only a few shell collectors and from their invertebrates No large specimens were findings we know that several endemic species collected The only other sympatnc Conus occur there Cypraea teulen Cazenavette, species were Conus ardtsiaceus Kiener, 1845 1846, Conus boschi Clover, 1972, Acteon and Conus boschi Clover, 1972 These facts eloiseae Abbott, 1973, Latirus bonmeae gave nse to the idea that our "juvemles" should Smythe, 1985, Conus stocki Coomans & be considered as two small Conus species Moolenbeek, 1990 Other Masiran species are After companson with other Indo-Pacific found on the neighbouring coast of Oman too, species of the genus Conus we are convinced which can be explained by the fact that the that both species belong to unnamed taxa island is only separated from the Arabian which are descnbed below All matenal is peninsula by a narrow strait of about 6 to 10 deposited m the Zoologisch Museum m depth Amsterdam (Umversity of Amsterdam), the Several years ago Dr D T Bosch showed Netherlands, unless otherwise stated us some small,wom cone shells fi'om Masirah island, which at first sight we considered juvemles When publishing on the family * Studies on Conidae no 17/ Studies on the Conidae from Oman m detail (COOMANS & manne molluscan fauna of Oman, no 7 19 APEX 8(1) 19-26, mars 1993 New Cones from Oman MOOLENBEEK & COOMANS TAXONOMY Operculum homy, orange-brown, measurements 2 8x09 mm Ammal not Conus boschorum n. sp. studied alive After its preservation in alcohol Figs 1-6, 17 It was blackish, eye stalks white with the eye black Proboscis with a white tip Type Material Holotype (figs 1-2) in Zoologisch Museum Amsterdam(ZMA Moll Variability There is little variation in 3 92 001) and 370 paratypes (ZMA Moll shape of the shells However, the colour 3 92 002), partly preserved in alcohol pattern is most vanable (figs 3-6) Especially Paratypes will be distnbuted to the Oman juvenile specimens can be completely Natural History Museum (Muscat), the yellowish to orange (fig 6) with only dark National Museum of New Zealand brown spots on the spire Larger specimens (Wellington) and to the pnvate collections of have grey to nearly black colour patterns Dr D Bosch (USA), Dr D Rockel About 70% of the studied matenal consists of (Germany), R M Filmer (England) , P L van specimens with the black colour pattern, but Pel and H Dekker (both the Netherlands) the larger specunens are more greyish The pattern is very irregular, although in general a Type Locality Sultanate of Oman, lighter mid-body band is present Fine spiral Masirah Island, Sur/Umm Rasas, 0 1-06 m bands of brown spots can cover the entire below low tide ,Sta 91/99, November 1991 body whorl The largest paratype has a length leg RG Moolenbeek «fe H Dekker of 12 6 mm, width 7 0 mm Description of the Holotype (figs 1-2) Other Material Studied One shell at Length 11 0 mm, width 5 9 mm Shell Umm Rasas, Sta 91/99, Nine shells at Ras turbinate, thin, glossy, low biconical Abu Zabil, Rounders Bay, 6 m SCUBA, Sta Protoconch paucispiral, 1 1/2 bulbous whorls, 91/123, leg Gary Keat (RAFO) Two shells partly with an indented sculpture Teleoconch were found on the west coast of Masirah with 4 whorls Spire stepped, straight to a little Island, Valley of the Moon beach. Sta 91/93, concave, whorls canaliculated with irregular Another two living specimens were collected growth lines Shoulder sharply angulated on Al Hallaniyah (Sta 91/60), which have a Body whorl smooth except lower third which more pronounced sculpture on the protoconch has 11 spiral grooves on the ventral and 7 on To find out whether these Al Hallaniyah the dorsal side specimens are conspecific more matenal and fiirther research is needed All matenal Aperture slender, somewhat expanding collected in November 1991, leg RG towards the base Moolenbeek & H Dekker Colour Spire white with irregular dark brown spots On the bodywhorl are 8 brown spots which continue below the shoulder and Etymology Conus boschorum is named are connected to a broader blackish band Just after Donald and Eloise Bosch, to express our below the shoulder a small light band is respect for all the activities they have mitiated followed by a somewhat broader blackish to stimulate malacological research in Oman band Middle of bodywhorl with a light band m which are about 5 fine brown spotted Discussion Due to its small size, this new spirals In this light band are many irregularly species could easily be considered a juvenile of formed milky white spots Base blackish with a larger species Juvemles of Conus irregular white spots in Periostracum thin, acummatus Hwass, 1792 , with a more slender nearly transparent, more prominent on the outline, have less canaliculated whorls with shoulder forming fine fringes one or two, sometunes vague, spirals on it Also, that species has never been recorded 20 MOOLENBEEK & COOMANS New Cones from Oman APEX 8(1-2) 19-26, mars 1993 from Oman Conus boschorum n sp lives applied to C exiguus Lamarck, 1810, type sympatncally with C ardisiaceus Kiener, species of Thoraconus Da Motta, 1991 1845, C boschi Clover, 1972 and C biraghu We are of the opinion that the genene omanensis n ssp Of these three taxa, only classification of the Comdae by DA MOTTA juvenile specimens of C ardisiaceus show (1991) IS premature The 30 new subgenera he resemblance but differs in having spiral descnbed, will create more confiision rather grooves on the spire whorls (figs 7-8) Also its than being a senous attemp to classify the shape IS more bulbous and it grows larger In hundreds of (sub)species m this family The shape and size C rutilts Menke, 1843 from taxonomy of the Comdae is still far from bemg southwest Australia shows similanties settled This is due to the large number of However, its protoconch is more nipple like species (about 600 recent) and the growmg and the spire is slightly coronated C klemae number of species [names] every year Also Cotton, 1953 from western Australia has a vanability, abundance of (sub)specific names more or less similar outline but has spiral (far over 2000 fossil and recent), homonymy, grooves on the spire Also that species grows synonymy , unknown distnbution patterns and much larger incorrect localities need more research We have two live collected shells from Al Therefore we prefer to use the genus Conus Hallaniyah [=Kuna Muria Island], which might be C boschorum n sp However there are slight differences in colourpattem and Conus biraghii omanensis n.ssp. protoconch structure Additional material is Figs. 11-16, 18 needed for companson Type Material Holotype (ZMA Moll 3 92 003) and 110 paratypes, partly preserved Conus biraghii m alcohol (ZMA Moll 3 92 004) Paratypes (G. Raybaudi, 1992) will be distnbuted to the Oman Natural Figs 9-10 History Museum (Muscat), the National Museum of New Zealand (Wellington) and to This small species was recently descnbed the pnvate collections of Dr D T Bosch,Dr as Leptoconus (Thoraconus) biraghii from D Rockel, P L van Pel, R M Fihner and H Somalia The description was based on a Dekker rather monomorph sample, and details on the sculpture of the protoconch were not available Type Locality Sultanate of Oman, We could study one of the paratypes of C Masirah Island, Sur /Umm Rasas, 0 1-0 6 m biraghu (figs 9-10) present in the collection of below low tide. Sta 91/99 November 1991 D Rockel (Germany) leg R G Moolenbeek & H Dekker From Masirah Island we have specimens of a small Conus species, which has a number Description of the Holotype (Figs 6-7) of characters in common with C biraghu Length 7 7 mm, width 3 6 mm Shell small, Our companson leads to the conclusion that a biconic, slender, rather solid Protoconch of 1 subspecific status for the Masirah matenal is 1/2 whorls Imtial part mainly white with justified brown sutures, remaming part brown with The shell characters of C biraghu do not mmute opisthoclme axial nms (folds) assign it to Leptoconus , which is based on Teleoconch consistmg of 4 1/2 whorls First type species C amadis Gmelin, 1791 The teleoconch whorl with one strong spiral latter is a large species with different size, groove, gradually a 2nd and 3rd appear shape, sculpture and pattern The same can be Whorls with microscopic growth Imes 21 APEX 8(1): 19-26, mars 1993.