Cainozoic Research, 9(1), pp. 121-133, June 2012 The genera Engina and Ameranna nov. gen. (Mollusca: Gastropoda, Buccinoidea, Buccinidae, Pisaniinae) from the Western Atlantic Neogene Bernard Landau!* and Geerat J. Vermeij" 1Centro de Geologia da Universidade de Lisboa. Campo Grande, 1749-016 Lisboa, Portugal and International Health Centres, Av. Infante de Henrique 7, Areias São João, P-8200 Albufeira, Portugal; [email protected] 2Department of Geology, University of California at Davis, One Shields Avenue, Davis, CA 95616 USA; [email protected] *Corresponding author Received: 16 April 2012; revised version accepted 20 April 2012 The first occurrence of the cosmotropical pisaniine buccinid gastropod genus Engina Gray, 1839 was previously in the lower Gatun Formation (late Miocene) of Panama. Here we describe four new fossil species: E. cantaurana nov. sp., from the early Miocene of Venezuela (the oldest known species of Engina, with an unusually high spire), E. gigas nov. sp., from the late Miocene and early Pliocene of the Dominican Republic (the largest known Engina, with an erect inner lip and obsolete parietal denticle), E. latior nov. sp. from the late Miocene and early Pliocene of the Dominican Republic (a more typical species of Engina in terms of apertural dentition) and Engina moinensis nov. sp from the Pleistocene of Costa Rica and the Bocas del Toro Area (a species with possible paciphile affinities). We propose the new pisaniine genus Ameranna (type species: Anna florida García, 2008) for four living Carib- bean species and for two fossil species: A. primitiva nov. sp., from the early Miocene of Venezuela (the oldest known species of Ameranna) and the new Pliocene species A. minuscula nov. sp. from the Dominican Republic. The new genus differs from the early Oligocene to Recent eastern Atlantic genus Anna by having a lirate rather than denticulate outer lip. KEY WORDS: Neogene, tropical America, Gastropoda, Pisaniinae, new genus, new species Introduction Material and methods Despite years of taxonomic study, the fossil record of The material described here is from the Panama Paleon- tropical America still contains many undescribed spe- tology Project (PPP) collection and the Gibson-Smith cies. This situation applies especially to hard-bottom collection, both housed in the Naturhistorisches Museum taxa, which preserve less reliably than those from sand Basel (NMB coll.), Switzerland and the Bernard Landau or mud bottoms. To help redress this lack of taxonomic collection (BL coll.), now deposited in the Naturhis- work, we here describe six new fossil species from hard- torisches Museum Wien (NHMW coll.), Vienna, bottom habitats in the Neogene of tropical America. All Austria. We have also consulted the collections in the the species in question belong to the buccinid neogastro- Zoological Museum, University of Amsterdam (ZMA), pod subfamily Pisaniinae. The Netherlands. Vermeij (2001, 2006) informally recognized three mor- We have adopted the recent recommendation of the phological groups within Pisaniinae, those centered on International Commission on Stratigraphy – accepted by the genera Pisania Bivona-Bernardi, 1832, Cantharus the IUGS on June 30, 2009 – on the redefinition of the Röding, 1798; and Engina Gray, 1839. The Engina Pleistocene (now including the Gelasian Stage/Age as its group, characterized by a shell with a narrow, strongly lowermost unit), and the concomitant formal redefinition denticulate aperture and the presence of distinct columel- of the base of the Quaternary System/Period (and thus lar folds, is the least well represented in the fossil record the Neogene/Quaternary boundary) by the Monte San but the most species-rich in the Recent fauna. Four of the Nicola GSSP and thus to be coincident with the bases of six species we describe here belong to Engina in the the Pleistocene and Gelasian. The Plio-Pleistocene broad sense, and thus add significantly to the fossil re- boundary is now pushed back to 2.59 Ma (Riccardi, cord of that group. 2009). - 122 - Systematic Palaeontology cords and threads. The aperture is narrow and more or less parallel-sided or elongate pyriform, bordered abaxi- Superfamily Buccinoidea Rafinesque, 1815 ally by a slightly expanded and thickened terminal varix Family Buccinidae Rafinesque, 1815 and on its adaxial side by an adherent inner lip. At the Subfamily Pisaniinae Gray, 1857 adapical end of the aperture, a distinct anal canal is Genus Engina Gray, 1839 formed between the adapicalmost (anal) tooth on the outer lip and a parietal tooth on the inner lip, but there is Type species – Engina zonata Gray, 1839 by subsequent no adapical notch in the outer lip. Adults bear five or designation Gray, 1847 = Purpura turbinella Kiener, more teeth on the inner side of the outer lip some dis- 1836 (see Orr, 1962), Recent, Caribbean. tance in from the edge. There is typically a gap between these teeth and the anal tooth, and the adapical outer-lip Remarks – As currently understood, Engina comprises a tooth is larger than the others. The edge of the outer lip is cosmotropical and warm-temperate southern-hemisphere erect, sharp, and slightly crenulated by the ends of the group of small, thick-shelled, determinately growing external spiral cords. There are no spiral ridges (lirae) on gastropods found on intertidal and shallow subtidal the inner side of the outer lip. The adult inner lip bears rocky bottoms (Cernohorsky, 1971, 1975; Ponder, 1972). small denticles along its edge, and has two abapical spi- Engina turbinella Kiener, 1836 (the type species) and ral folds, an entrance fold to the siphonal canal and, im- other typical members of the genus have shells with a mediately adapical to it, a much weaker second fold. biconic shape, weak abapical constriction, a relatively Cernohorsky (1975) described radial lirae, present on the short siphonal protuberance whose axis more or less par- parietal callus, as a characteristic feature of the genus. allels that of the shell, and teleoconch sculpture consist- However, these parietal lirae are not present in all En- ing of narrowly rounded axial ribs overridden by spiral gina species. Figure 1. Engina turbinella (Kiener, 1836), illustrating terminology of apertural features for the genus (adapted from Cernohorsky, 1975). Besides E. turbinella, which is a species (or species siphonal protuberance is often longer than in typical En- complex) in the Caribbean with low axial ribs and very gina, and, as previously mentioned, the parietal lirae are weak spiral cords, at least two other Recent tropical not present in all species. A wide range of shell form is American species conform to this general description, seen in the Recent American species, which include the except that their spiral sculpture and axial ribs are con- very short and squat E. pulchra (Reeve, 1846), strongly siderably more prominent. These are the eastern Pacific shouldered E. pyrostoma (Sowerby I, 1832), both of E. maura (Sowerby, 1832) and E. tabogaensis Bartsch, which are from the eastern Pacific, and the elongate Flo- 1931. In the Indo-West Pacific, species with similar ridian E. corinnae Crovo, 1971. The Brazilian E. gon- outer-lip dentition have a notably thickened outer lip and calvesi Coltro, 2005 is an outlier, with a less biconic low axial and spiral sculpture. They include, among oth- shell, with much weaker sculpture, more rounded, less ers, the widespread E. mendicaria (Linnaeus, 1758) and angular whorls and a wider pyriform aperture, but the E. phasinola (Duclos, 1840). character of the apertural denticles and folds is character- Not all species placed in Engina conform to this charac- istic for the genus. In all Recent Caribbean members of terization. In these species, the outer-lip denticles are the genus, including E. goncalvesi, the protoconch is more numerous and less differentiated in size, and the paucispiral, consisting of 1.5 whorls. Watters (2009) - 123 - described Hesperisternia itzamnai, a very rare Recent unrecorded from the fossil record of the Indo-West Pa- shell from eastern Mexico and compared it to the eastern cific. The only record of which we are aware is that of Pacific H. jugosa (Adams, 1852) and placed this and the van Regteren Altena (1950), who recorded E. sinensis Brasilian Engina janowskyi Coltro, 2005 in the genus Melvill, 1895 [a synonym of E. curtisiana (E.A. Smith, Hesperisternia, which was reviewed by Vermeij (2006). 1884) according to Wilson (1994)] from the Kendeng Both these species show shell features characteristic of Beds (Pucangan Formation, early Pleistocene) of Java, Engina, and should be included in this genus. Indonesia. Numerous Indo-West Pacific species also diverge from the typical form (see also Ponder, 1972). The species we describe in this paper fall into several categories, includ- Engina cantaurana nov. sp. ing typical Engina (see E. latior nov. sp.). As discussed Figs 2-7 below, we consider all of them to belong to Engina in the broad sense. Dimensions and type material – Holotype NHMW Our assignment of the three new Engina species to En- 2010/0124/0001, height 18.6 mm, width 9.8 mm (Figs 2- gina rests on comparisons with other genera that resem- 4); paratype 1 NHMW 2010/0124/0002, height 16.8 mm, ble, and may be related to that genus. The Indo-West width 9.7 mm (Figs 5-7); paratype 2 NHMW Pacific genus Clivipollia Iredale, 1929, has shells charac- 2010/0124/0003, height 21.4 mm; paratype 3 NHMW terized by broad, rounded axial ribs, a glossy surface, 2010/0124/0004, height 21.4 mm. and a terminal varix with denticles of relatively even size situated on its inner side very close to the slightly con- Etymology – From the locality of Casa Cantaure, Para- vex, crenulated edge. Further inside the aperture, the guaná Peninsula, where this species is found. outer lip bears long, prominent spiral lirae. There is no parietal denticle. The siphonal protuberance is demar- Type locality – 1 km southwest of Casa Cantaure, about cated from the rest of the shell by a well-marked con- 10 km west of Pueblo Nuevo, Falcón, Venezuela (= lo- striction, and shows a strong dorsal curvature, unlike the cality GS12PGNA of Gibson-Smith & Gibson-Smith, nearly straight canal of Engina.