(Cancellaria) Decussata Canc Ellaria
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NOTES ON THE MOLLUS CAN FAUN A OF THE MONTEZl'MA FORMATION , COSTA RICA RICH ARD E. PETIT N ORTH MYRTLE BEACH, SOUTH CAROLI NA Only recently has a paper on th e Canc ellaria (Cancellaria) darwini Montezuma Formation (Pliocen e Petit, 1970. The specim n illu--;trat<>dIp. Pleistocene of Costa Rica) published in 226, pl. 2, fig. 23) is a juvenile ('ancellaria 1986 come to my attention. This paper is s.s. , pro bably C. albida H nds, 1A1,{,ot •hf, by Teresita Aguilar and Rudolf Fischer , Recent Panamic- Pacific fauna, bt..t po. with the Gastropoda being by Aguilar and tive ident ificatio n is not possibh f om thP the Bivalvia by Fischer. As faunal studi es illustrati on. It is definitely not (' duru 111z of this type are used in various compil a which , alth ough p!aced in ('rir,u>/lanu _.., tions for both spatial and temporal rang es by Keen ( 1971, p. 64 7 l. was st, tui rn ts of taxa, the present paper is written t o original descript ion to !,,ck tre :tro11g r.01 point out incorrect identifications of both umell ar folds of Cancell,.,,ia --; arict genus-group and species-group taxa , par shoul d be placed in .'ome ·uhg0nu 1d r ticularly in the Cancellariidae as well as t han the nom inot.r pica! Tb• Ret en some others. The cited identification s species is somew hat littoriniform r out incorrectly indicate, for example , th at line and the shell is weakly cane •I' tE- r > Recent deep-water species from th e beaded as is the l½ontezum 1 specirr( '1 1 Galapagos Islands once lived in much Cancell aria (AgatrixJ deroyae £-- i shallower water during the Pliocen e 1970. The figured specimen fol ~ fi ~> Pleistocene. The stratigraphic portion of is C.(C.) urceolata Hinds. 1~1.1. a Rectnt the paper showing ranges of the speci es species which ranges f'rom tre nulf o studied should send up a warning flag to California to Ecuad or. Cam 0 tlarta Jerm the reader, as the taxa listed are an eclec ae, now prope rly placed int e gtnu · tic lot , containing species previously A dmetula , is known onlv from 110-~( 0 known only as endemics from the Alum meters off the Galapagos Island.., and Bluff Formation of Florida (Miocene ), th e bears no resemb lance to the shell figured. Tubara Formation of Colombia (Pliocen e), Cancella ria (Euclia) coda-zii deep-water Recent species from t h e Anderson , 1929. This specH' W'l'-> Galapagos Islands, and other unlikel y d escrib ed from the Tubard For'lla ion cohabitants. (P liocen e) of Colombia and has be£>n My particular interest is in the family r eported from various deposits in Central Cancellariidae and the relevant species in America . The figured Montezuma :p •c1 this study are: men (pl. 3, fig. 24) is not C. codazzu. whicn Cancellaria (Cancellaria) decussata h as a tabul ate shell without strong nodl.., Sowerby, 1832. The figured specimen (p. at th e should er and is more con:trictNl 226, pl. 2, fig. 26) does appear to be a ant eriorly than the specimen figured. fhf' species of Cancellaria s.s. , although the Mo n t ezum a specimen has the genl·ra, columellar folds are hidden by matrix so shap e and sculp ture of C. l a<;sidtformi ~ this cannot be determined with certainty. So werby, 1832, a shallow-wat£ r Rl'u r:t However, it is not C. (C.) decussata, which sp ecies ranging from the Gulf of C,liforria is a Recent species ranging from the Gulf to Peru and is probably that specie . of California to the Galapagos Islands and A fifth membe r of the Cancellc..rioi<lea also known from beds in the Galapagos figur ed in thi ·s paper (pl. 2, fig. 22J 1s thought to be Pleistocene in age. Tritonoh a rpa siphona ta (Reeve, 1844 ), Cancellaria decussata has much finer which app ears to be correctly identifit'd, sculpture, which appears as beading, although cite d as a Colubra ria, which was unlike the specimen figured which is wide the usual placement when the paper was ly reticulate. Also , the Recent shell is not written . so constricted behind the siphonal fasciole. A detail ed critique of the identification s This Montezuma specimen cannot be posi of the Mon tezuma specimens figured in tively identified with any described species this pap er is not being attempted. but it is very close to , if not the same as, C. How ever , workers are cautioned about cit corrosa Reeve, 1856, a rare species living ing taxa from this work without examining off western Mexico. the tax a closely. Besides the cancellariids 151 152 Tulane Studies in Geology and Paleontology Vol. 29 listed above, some obvious errors in identi typhis ) gabbi (Brown and Pilsbry) but is fication of other gastropods are: the Recent eastern Pacific Haustellotyphis In the stratigraphic portion of the paper cumingi (Broderip, 1833 ). (p . 214) it is pointed out that the genus In addition to the two cancellariids iden Marginella, although occurring in the tified as endemic deep-water Galapagos Montezuma fauna is not present in the species, a third species is also so treated. Recent Panamic-Pacific fauna. This state It is said to be Compsodrillia gracilis ment is based upon a species listed and McLean and Poorman and is represented figured (p. 226, pl. 2, fig. 19) as Marginella (pl. 3, fig. 26) by a badly broken shell lack mindiensis Cossmann, 1913. The figured ing its apex, at least one third of its body specimen is not a Marginella but is a whorl, and the anterior portion. Because Prunum. The only reference cited is that of the presence in the Recent Panamic of Olsson (1922, p. 268), who placed the Pacific fauna of similar species, the precise species in Marginella, as had Cossmann identification of this partial specimen originally. No mention is made of should be examined by turrid specialists Woodring's treatment of this species (1970, before admitting this taxon to a shallow to p . 332, pl. 51, figs. 10, 11), although his moderate depth Pliocene-Pleistocene fauna work is cited as a reference. Woodring in Costa Rica. placed this taxon in the synonymy of Prunum gatunense (Brown and Pilsbry, LITERATURE CITED 1911) and referred to a similar unnamed species living off Costa Rica. The AGUILAR, T., and R. FISCHER , Moluscos de la Montezuma specimen may be Prunum Formaci6n Montezuma (Plioceno-Pleistoceno ; gatunense, but in any case the genus Costa Rica): Geologica et Paleontologica , v. Marginella does not occur in the Monte 20, p. 209-241, pls. 1-6. zuma Formation as stated. KEEN , A. M., 1971 , Sea Shells of Tropical West Plate 2, fig. 8, is labeled as Distorsio America . Second Edition. Stanford University (Rhysena) floridana (Gardner). The fig Press, Stanford, California. xiv + 1064 p., 22 ured specimen is not the Alum Bluff color pls., ca. 4000 text-figs. (Miocene) species described by Gardner. OLSSON , A. A., 1922, The Miocene of Northern Plate 2, fig. 11, is labeled Cymatium cf. Costa Rica: Bulls. Amer. Paleontology, v. 9, wiegmanni (Anton) but it is a Distorsio, no. 39, p. 173-481 , pls . 4-35 [dual pagination ; not a Cymatium. also numbered: 1-309 , pls. 1-32]. Plate 2, figs. 15 and 16, are labeled PETIT, R. E., 1970, Notes on Cancellariidae Eupleura sp., but the figures are of a (Mollusca: Gastropoda ) - II: Tulane Stud. cymatiid . Geol. Paleont. , v. 8, no. 2, p. 83-88, pl. 1. Plate 2, fig. 17, is said to be Eupleura WOODRING, W. P., 1970, Geology and paleon lehneri Jung, which was described from tology of Canal Zone and adjoining parts of the late Miocene of Trinidad, but the speci Panama. Description of Tertiary mollusks men is the Recent eastern Pacific E. muri (Gastropoda: Eulimidae , Marginellidae to ciformis (Broderip, 1833). Helminthoglyptidae ): U.S. Geol. Survey , Plate 2, fig. 18, is identified as the Prof. Paper 306-D, p. 299-452, pls. 48-66. Gatun Formation species Typhis (Pilsbry- February 26, 1997 .