866:. The differences between the two orders is subtle and hinges on size and on details of the radula, shell, and foot. Specifically, the Dentaliids are the physically larger of the two families, and possess a shell that tapers uniformly from anterior (widest) to posterior (narrowest); they also have a foot which consists of one central and two lateral lobes and which bends into the shell when retracted. The Gadilids, on the other hand, are much smaller, have a shell whose widest portion is slightly posterior to its aperture, and have a foot which is disk-like and fringed with tentacles which inverts into itself when retracted (in this state resembling a pucker rather than a disk).
870:
113:
409:
151:
383:
603:
1114:
scaphopod nervous system demonstrated that both scaphopods and cephalopods share a similar nervous system structure, with ventrally shifted pedal nerves and lateral nerves that extend dorsally. These similarities led to the conclusion that scaphopods are sister to the cephalopods with gastropods as sister to them both. More recent research, including the sequenced genome of tusk shells, support the
Diasoma model with bivalves as the sister group.
395:
255:
758:. Furthermore, they also appear to be the only molluscs with openings that directly connect the hemocoel with the surrounding water (through two "water pores" located near the nephridial openings). These openings may serve to allow the animal to relieve internal pressure by ejecting body fluid (blood) during moments of extreme muscular contraction of the foot.
1105:, however their phylogenetic relationship with the other members of this subphylum remains contentious. The Diasoma concept proposes a clade of scaphopods and bivalves based on their shared infaunal lifestyle, burrowing foot, and possession of a mantle and shell. Pojeta and Runnegar proposed the extinct
594:
and
Steiner, "he apex of the shell and mantle are anatomically dorsal, and the large aperture is ventral and anterior. Consequently, the concave side of the shell and viscera are anatomically dorsal. The convex side has to be divided into anteriorly ventral and dorsally posterior portions, with the
683:
that breaks the bit into smaller pieces for digestion. The radulae and cartilaginous oral bolsters of the
Gadilidae are structured like zippers where the teeth actively crush the prey by opening and closing on it repeatedly, while the radulae and bolsters of the Dentaliidae work rachet-like to pull
646:
of a scaphopod is entirely within the shell. The foot extends from the larger end of the shell, and is used to burrow through the substrate. The scaphopod positions itself head down in the substrate, with the apical end of the shell (at the rear of the animal's body) projecting upward. This end
1113:
as the stem group. A review of deep molluscan phylogeny in 2014 found more support for the scaphopods, gastropods, or cephalopods than for scaphopods and bivalves, thus the shared body features of scaphopods and bivalves may be convergent adaptations due to similar lifestyles. Analysis of the
833:
larva that more closely resembles the adult, but lacks the extreme elongation of the adult body. The three-lobed foot originates prior to metamorphosis while the cephalic tentacles develop post metamorphosis. Scaphopods remain univalved throughout their morphogenesis contrary to bivalves.
1420:
Sumner-Rooney, Lauren H.; Schrödl, Michael; Lodde-Bensch, Eva; Lindberg, David R.; Heß, Martin; Brennan, Gerard P.; Sigwart, Julia D. (2015). "A neurophylogenetic approach provides new insight to the evolution of
Scaphopoda: A neurophylogenetic approach in Scaphopoda".
625:
The shells of the members of the
Gadilida are usually glassy-smooth and narrow, with a reduced aperture. This along with other structures of their anatomy allows them to move with surprising speed through loose sediment to escape potential bottom-dwelling predators.
662:
from the water. Unlike most other molluscs, there is no continuous flow of water with a separate exhalant stream. Instead, deoxygenated water is expelled rapidly back through the apical aperture through muscular action once every ten to twelve minutes.
589:
The morphological shape of the scaphopod body makes it difficult to orient it satisfactorily. As a result, researchers have often disagreed as to which direction is anterior/ posterior and which is ventral/ dorsal. According to
781:
A separate set of pedal ganglia lie in the foot, and a pair of visceral ganglia are set further back in the body, and connect to pavilion ganglia via long connectives. Radular and sub-radular ganglia are also present, as are
629:
The
Dentalids, by contrast, tend to have strongly ribbed and rough shells. When they sense vibrations anywhere around them, their defensive response is to freeze. This makes them harder to detect by animals such as
1629:
Guralnick, R.; Smith, K. (1999). "Historical and biomechanical analysis of integration and dissociation in molluscan feeding, with special emphasis on the true limpets (Patellogastropoda: Gastropoda)".
798:, or other distinct sensory organs. However, scaphopods do possess genes involved in photoreceptor formation and function implying scaphopods may have had eyes that degenerated over evolutionary time.
647:
seldom appears above the level of the substrate, however, as doing so exposes the animal to numerous predators. Most adult scaphopods live their lives entirely buried within the substrate.
1578:
Wanninger, Andreas; Haszprunar, Gerhard (2001). "The expression of an engrailed protein during embryonic shell formation of the tusk-shell, Antalis entalis (Mollusca, Scaphopoda)".
755:
387:
1130:
1124:
1963:
727:(gills) and blood vessels; the blood is held in sinuses throughout the body cavity, and is pumped through the body by the rhythmic action of the foot. The
1673:
Ellis L. Yochelson; Royal H. Mapes; Doris
Heidelberger (2007). "An enigmatic molluscan fossil from the Devonian of Germany: scaphopod or cephalopod?".
1071:
1822:
Schrödl, Michael; Stöger, Isabella (2014-12-25). "A review on deep molluscan phylogeny: old markers, integrative approaches, persistent problems".
1731:
Pojeta, John; Runnegar, Bruce (1976). "The paleontology of rostroconch mollusks and the early history of the phylum
Mollusca". Professional Paper.
400:
2428:
2287:
1090:
1089:. However, a competing hypothesis suggests a Devonian/Carboniferous origin from a non-mineralized ancestor, or from a more derived, Devonian,
1009:
988:
2313:
1077:
787:
2433:
1521:"Remnants of ancestral larval eyes in an eyeless mollusk? Molecular characterization of photoreceptors in the scaphopod Antalis entalis"
1643:
369:
707:. A digestive gland secretes enzymes into the stomach, but, unlike some other molluscs, does not digest the food directly itself. The
1109:
as the stem group of the
Diasoma. An alternative hypothesis proposes the cephalopods and gastropods as sister to the scaphopods with
2423:
2261:
2300:
754:
close to the anus. The tusk shells appear to be the only extant molluscs which completely lack the otherwise standard molluscan
599:, the large aperture with the foot is anterior, the apical area posterior, the concave side dorsal and the convex side ventral."
2001:
687:
The massive radula of the scaphopods is the largest such organ relative to body size of any mollusc (among whom, except for the
731:, a characteristic feature of all other groups of mollusca, has been considered totally lost or reduced to a thin fold of the
1475:
1401:
1375:
Reynolds, Patrick D. (2006). "Scaphopoda: The Tusk Shells". In Sturm, Charles F.; Pearce, Timothy A.; Valdés, Ángel (eds.).
2305:
1301:
Giribet, G.; Okusu, A, A.; Lindgren, A.R., A. R.; Huff, S.W., S. W.; Schrödl, M, M.; Nishiguchi, M.K., M. K. (May 2006).
679:, sift through the sediment and latch onto bits of food, which they then convey to the mouth. The mouth has a grinding
2002:
Steiner, G.; Kabat, A. R. (2001). Catalogue of supraspecific taxa of
Scaphopoda (Mollusca). Zoosystema. 23(3): 433-460
1773:"The Continuing Debate on Deep Molluscan Phylogeny: Evidence for Serialia (Mollusca, Monoplacophora + Polyplacophora)"
1303:"Evidence for a clade composed of molluscs with serially repeated structures: monoplacophorans are related to chitons"
2028:
1923:
1885:
1503:
1218:
691:, the presence of which is a defining characteristic). The remainder of the digestive system consists of a digestive
2385:
885:
2318:
566:
are unfamiliar with them; their shells are not as common or as easily visible in the beach drift as the shells of
539:
marine molluscs. Shells of species within this class range in length 0.5–18 cm (0.20–7.09 in) (with
362:
1771:
Stöger, I.; Sigwart, J. D.; Kano, Y.; Knebelsberger, T.; Marshall, B. A.; Schwabe, E.; Schrödl, M. (2013).
2209:
2196:
1942:
Scaphopoda of the tropical Pacific and Indian Oceans, with description of 3 new genera and 42 new species
1757:
1076:
has been interpreted as an early antecedent of the scaphopods, implying an evolutionary succession from
869:
150:
17:
2367:
2328:
2214:
355:
650:
Water enters the mantle cavity through the apical aperture, and is wafted along the body surface by
112:
2390:
2413:
1063:
2136:
811:
2354:
1391:
2349:
2021:
2377:
2341:
1465:
2292:
2235:
2183:
2174:
1314:
1255:
711:
opens on the ventral/ underside of the animal, roughly in the middle of the mantle cavity.
207:
8:
2438:
2418:
724:
555:
1318:
1259:
1977:
1847:
1799:
1772:
1744:
1690:
1655:
1611:
1555:
1520:
1446:
1337:
1302:
1278:
1243:
740:
634:, which can sense the electrical signals given off by the most minute muscle movement.
145:
1915:
1210:
2336:
2222:
1929:
1919:
1881:
1839:
1804:
1647:
1603:
1595:
1591:
1560:
1542:
1499:
1471:
1438:
1397:
1342:
1283:
1224:
1214:
1135:
911:
843:
744:
408:
1981:
1865:
Genomes of enigmatic tusk shells provide new insights into early Molluscan evolution
1851:
1694:
1659:
1450:
2227:
2188:
2116:
2014:
1911:
1864:
1831:
1794:
1784:
1732:
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1639:
1615:
1587:
1550:
1532:
1430:
1332:
1322:
1273:
1263:
1206:
1183:
1038:
948:
901:
643:
478:
434:
328:
132:
2201:
1672:
1835:
1268:
608:
525:
333:
312:
281:
2110:
2067:
1307:
Proceedings of the National Academy of Sciences of the United States of America
720:
529:
338:
122:
1537:
1187:
2407:
2159:
2104:
2057:
1843:
1599:
1546:
1106:
958:
735:; however, according to more recent studies, the muscular, regularly beating
591:
562:). Because of this subtidal habitat and the small size of most species, many
271:
262:
70:
1327:
382:
2052:
1933:
1808:
1651:
1607:
1564:
1442:
1346:
1287:
1228:
1110:
928:
847:
692:
563:
1996:
Catalog of species-group names of Recent and fossil Scaphopoda (Mollusca).
1948:, Volume 14 Mémoires du Muséum National d'Histoire Naturelle, 167 189-379.
1789:
1644:
10.1002/(SICI)1097-4687(199908)241:2<175::AID-JMOR7>3.0.CO;2-0
2274:
2168:
1151:
1139:
1080:
1028:
997:
938:
918:
826:
791:
732:
45:
1419:
2077:
2072:
1968:
1941:
1686:
1300:
1102:
1085:
892:
859:
783:
767:
751:
596:
578:
559:
544:
343:
302:
223:
192:
90:
55:
2006:
1434:
2279:
2248:
1018:
968:
807:
795:
704:
696:
577:
Molecular data suggest that the scaphopods are a sister group to the
567:
276:
162:
95:
2130:
1174:
Steiner, G. . (1992). "Phylogeny and Classification of Scaphopoda".
394:
254:
2266:
2253:
2153:
2082:
1498:. Philadelphia, PA: Holt-Saunders International. pp. 432–434.
1464:
Sturm, Charles F.; Pearce, Timothy A.; Valdés, Ángel, eds. (2006).
1379:. Boca Ratón, FL: Universal Publishers. pp. 229–238, esp. 231.
1147:
979:
863:
771:
736:
688:
672:
548:
536:
535:
with worldwide distribution, and are the only class of exclusively
246:
228:
182:
137:
127:
85:
80:
65:
60:
50:
1736:
1467:
The Mollusks: A guide to their study, collection, and preservation
1377:
The Mollusks: A guide to their study, collection, and preservation
2038:
830:
818:
occupying much of the posterior part of the body, and shed their
700:
631:
532:
100:
75:
581:, although higher-level molluscan phylogeny remains unresolved.
2062:
1519:
Wollesen, Tim; McDougall, Carmel; Arendt, Detlev (2019-10-19).
1154:, and are a possible indicator of early social stratification.
819:
774:
lie close to the oesophagus, and effectively form the animal's
680:
659:
172:
1910:. Advances in Marine Biology. Vol. 42. pp. 137–236.
1770:
1205:. Advances in Marine Biology. Vol. 42. pp. 137–236.
2362:
2240:
815:
775:
728:
651:
602:
307:
1146:
shells were also used to make belts and headdresses by the
719:
The scaphopod vascular system is rudimentary lacking heart
708:
655:
571:
496:
464:
458:
413:
1964:"Catalogue of supraspecific taxa of Scaphopoda (Mollusca)"
1876:
Crabtree, Pam J.; Campana, Douglas V., eds. (2005-06-21).
1364:. Vol. 6B: Mollusca II. Wiley-Liss, Inc. p. 719.
502:
452:
490:
443:
1244:"Gigantism and Its Implications for the History of Life"
1518:
1389:
1101:
The scaphopods are largely agreed to be members of the
1878:
Exploring Prehistory: How Archaeology Reveals Our Past
1360:
Shimek, Ronald; Steiner, Gerhard (1997). "Chapter 6".
1134:
were strung on thread and used by the natives of the
1062:
There is a good fossil record of scaphopods from the
508:
493:
487:
484:
449:
440:
437:
1880:(2nd ed.). McGraw-Hill Education. p. 233.
505:
499:
461:
455:
1577:
1470:. Boca Raton, FL: Universal Publishing. p. 2.
1066:onwards, making them the youngest molluscan class.
825:Once fertilized, the eggs hatch into a free-living
766:The nervous system is generally similar to that of
481:
446:
658:; the entire surface of the mantle cavity absorbs
1463:
862:(which may be paraphyletic) and the monophyletic
747:and is therefore considered the scaphopod heart.
2405:
1875:
1201:Reynolds, Patrick D. (2002). "The Scaphopoda".
801:
1730:
1666:
1628:
1457:
1383:
850:; some supplement this with vegetable matter.
750:Metabolic waste is excreted through a pair of
684:the prey into the esophagus, sometimes whole.
595:anus as the demarcation. Functionally, as in
2022:
1821:
1359:
1169:
1167:
363:
1390:Khanna, D.R.; Yadav, P.R. (1 January 2004).
1908:Molluscan Radiation - Lesser-known Branches
1203:Molluscan Radiation - Lesser-known Branches
2029:
2015:
1906:Reynolds, P. D. (2002). "The scaphopoda".
1707:
1164:
858:The group is composed of two subtaxa, the
547:tend to be larger than those of the order
370:
356:
111:
1798:
1788:
1701:
1554:
1536:
1336:
1326:
1277:
1267:
1905:
1374:
1200:
868:
770:. One pair each of cerebral and pleural
666:
601:
407:
393:
381:
120:Various Scaphopoda, from left to right:
2036:
1241:
1173:
822:into the water through the nephridium.
14:
2429:Extant Carboniferous first appearances
2406:
1493:
543:as the longest). Members of the order
2135:
2134:
2010:
1489:
1487:
412:Tusk shell necklace from Bronze Age (
27:Class of elephant tusk shell molluscs
2368:F1260A76-FFD4-FF8C-FF43-FD65FDE4FD20
2329:10f75ada-619b-426d-a523-c1564e9bef57
1415:
1413:
1362:Microscopic anatomy of invertebrates
24:
2434:Taxa named by Heinrich Georg Bronn
1904:For a comprehensive overview, see
1898:
1484:
714:
25:
2450:
1946:Résultats des Campagnes MUSORSTOM
1410:
853:
761:
1994:Steiner G. & Kabat A. 2004.
1592:10.1046/j.1525-142X.2001.01034.x
1057:
886:World Register of Marine Species
477:
433:
253:
149:
43:
2424:Mississippian first appearances
1869:
1858:
1815:
1764:
1724:
1712:and the origin of scaphopods".
1622:
1571:
1512:
1368:
1353:
1294:
1235:
1194:
875:Calliodentalium semitracheatum
584:
13:
1:
1916:10.1016/S0065-2881(02)42014-7
1777:BioMed Research International
1714:Acta Palaeontologica Polonica
1211:10.1016/S0065-2881(02)42014-7
1157:
829:larva, which develops into a
516:, from Ancient Greek σκᾰ́φης
1836:10.1080/00222933.2014.963184
1675:Paläontologische Zeitschrift
1269:10.1371/journal.pone.0146092
1176:Journal of Molluscan Studies
1117:
1096:
1052:
802:Reproduction and development
554:These molluscs live in soft
7:
1580:Evolution & Development
1423:Evolution & Development
10:
2455:
1998:Zoosystema 26 (4): 549-726
1824:Journal of Natural History
1494:Barnes, Robert D. (1982).
1396:. Discovery. p. 198.
837:
756:reno-pericardial apertures
615:
524:"foot"), are members of a
2143:
2096:
2045:
1538:10.1186/s13227-019-0140-7
880:(specimen at MNHN, Paris)
723:as well as corresponding
637:
620:
220:
215:
146:Scientific classification
144:
119:
110:
34:
675:around the foot, called
541:Fissidentalium metivieri
1328:10.1073/pnas.0602578103
1242:Vermeij, G. J. (2016).
1188:10.1093/mollus/58.4.385
1032:Scarabino in Boss, 1982
846:, feeding primarily on
881:
812:external fertilisation
612:
606:Anatomical diagram of
558:offshore (usually not
417:
405:
391:
388:Dentalium octangulatum
2350:Paleobiology Database
1940:Scarabino V., (1995)
1632:Journal of Morphology
872:
814:. They have a single
790:. Scaphopods have no
667:Feeding and digestion
605:
411:
397:
385:
1976:(3): 433–460. 2001.
1830:(45–48): 2773–2804.
1708:Peel, J.S. (2004). "
1496:Invertebrate Zoology
842:Tusk shells live in
295:About mollusc shells
41:Mississippian–Recent
1790:10.1155/2013/407072
1393:Biology of Mollusca
1319:2006PNAS..103.7723G
1260:2016PLoSO..1146092V
1131:Dentalium pretiosum
1125:Dentalium hexagonum
671:A number of minute
241:Part of a series on
1687:10.1007/BF02988386
983:Starobogatov, 1974
882:
878:(Boissevain, 1906)
613:
428:, technically the
418:
406:
392:
2401:
2400:
2337:Open Tree of Life
2137:Taxon identifiers
2125:
2124:
1752:Missing or empty
1477:978-1-58112-930-4
1435:10.1111/ede.12164
1403:978-81-7141-898-5
1313:(20): 7723–7728.
1136:Pacific Northwest
1083:molluscs such as
1043:
1033:
1023:
1014:
1002:
993:
984:
973:
963:
953:
943:
933:
923:
912:Calliodentaliidae
906:
897:
884:According to the
879:
844:seafloor sediment
380:
379:
334:Crustacean shells
329:Brachiopod shells
236:
235:
211:
16:(Redirected from
2446:
2394:
2393:
2381:
2380:
2371:
2370:
2358:
2357:
2345:
2344:
2332:
2331:
2322:
2321:
2309:
2308:
2296:
2295:
2283:
2282:
2270:
2269:
2257:
2256:
2244:
2243:
2231:
2230:
2218:
2217:
2205:
2204:
2192:
2191:
2179:
2178:
2177:
2164:
2163:
2162:
2132:
2131:
2117:Archinacelloidea
2031:
2024:
2017:
2008:
2007:
1985:
1944:P. Bouchet (ed)
1937:
1892:
1891:
1873:
1867:
1862:
1856:
1855:
1819:
1813:
1812:
1802:
1792:
1768:
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1740:
1728:
1722:
1721:
1705:
1699:
1698:
1670:
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1620:
1619:
1575:
1569:
1568:
1558:
1540:
1516:
1510:
1509:
1491:
1482:
1481:
1461:
1455:
1454:
1417:
1408:
1407:
1387:
1381:
1380:
1372:
1366:
1365:
1357:
1351:
1350:
1340:
1330:
1298:
1292:
1291:
1281:
1271:
1239:
1233:
1232:
1198:
1192:
1191:
1171:
1041:
1039:Wemersoniellidae
1031:
1021:
1012:
1001:Chistikov, 1979
1000:
991:
982:
971:
961:
951:
949:Laevidentaliidae
941:
931:
921:
904:
902:Anulidentaliidae
895:
877:
806:Scaphopods have
520:"boat" and πούς
515:
514:
511:
510:
507:
504:
501:
498:
495:
492:
489:
486:
483:
471:
470:
467:
466:
463:
460:
457:
454:
451:
448:
445:
442:
439:
372:
365:
358:
344:Sea urchin tests
257:
238:
237:
206:
154:
153:
115:
105:
42:
38:Temporal range:
32:
31:
21:
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2447:
2445:
2444:
2443:
2404:
2403:
2402:
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2348:
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2312:
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2286:
2278:
2273:
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2239:
2234:
2226:
2221:
2213:
2208:
2200:
2195:
2187:
2182:
2173:
2172:
2167:
2158:
2157:
2152:
2139:
2128:
2126:
2121:
2097:Extinct classes
2092:
2041:
2035:
1962:
1926:
1901:
1899:Further reading
1896:
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1506:
1492:
1485:
1478:
1462:
1458:
1418:
1411:
1404:
1388:
1384:
1373:
1369:
1358:
1354:
1299:
1295:
1254:(1): e0146092.
1240:
1236:
1221:
1199:
1195:
1172:
1165:
1160:
1150:culture of the
1120:
1099:
1072:Rhytiodentalium
1069:The Ordovician
1060:
1055:
1042:Scarabino, 1986
1022:Stoliczka, 1868
972:Chistikov, 1975
962:Chistikov, 1975
942:Chistikov, 1975
905:Chistikov, 1975
856:
840:
804:
764:
739:blood sinus is
717:
715:Vascular system
669:
654:. There are no
640:
623:
618:
609:Rhabdus rectius
587:
480:
476:
436:
432:
376:
339:Horseshoe crabs
321:Other seashells
205:
148:
106:
104:
103:
98:
93:
88:
83:
78:
73:
68:
63:
58:
53:
48:
40:
39:
36:
28:
23:
22:
15:
12:
11:
5:
2452:
2442:
2441:
2436:
2431:
2426:
2421:
2416:
2414:Mollusc shells
2399:
2398:
2396:
2395:
2382:
2372:
2359:
2346:
2333:
2323:
2310:
2297:
2284:
2271:
2258:
2245:
2232:
2219:
2206:
2193:
2180:
2165:
2149:
2147:
2141:
2140:
2123:
2122:
2120:
2119:
2113:
2111:Helcionelloida
2107:
2100:
2098:
2094:
2093:
2091:
2090:
2085:
2080:
2075:
2070:
2068:Monoplacophora
2065:
2063:Polyplacophora
2060:
2055:
2049:
2047:
2046:Extant classes
2043:
2042:
2034:
2033:
2026:
2019:
2011:
2005:
2004:
1999:
1991:
1990:
1989:
1988:
1987:
1986:
1957:
1956:
1950:
1949:
1938:
1924:
1900:
1897:
1894:
1893:
1886:
1868:
1857:
1814:
1763:
1723:
1700:
1681:(2): 118–122.
1665:
1638:(2): 175–195.
1621:
1586:(5): 312–321.
1570:
1511:
1504:
1483:
1476:
1456:
1429:(6): 337–346.
1409:
1402:
1382:
1367:
1352:
1293:
1234:
1219:
1193:
1182:(4): 385–400.
1162:
1161:
1159:
1156:
1122:The shells of
1119:
1116:
1098:
1095:
1059:
1056:
1054:
1051:
1050:
1049:
1048:
1047:
1046:
1045:
1035:
1025:
1006:
1005:
1004:
977:
976:
975:
965:
955:
945:
935:
925:
922:Children, 1834
915:
908:
896:da Costa, 1776
855:
854:Classification
852:
848:foraminiferans
839:
836:
808:separate sexes
803:
800:
763:
762:Nervous system
760:
716:
713:
668:
665:
639:
636:
622:
619:
617:
614:
586:
583:
401:Entalis laevis
378:
377:
375:
374:
367:
360:
352:
349:
348:
347:
346:
341:
336:
331:
323:
322:
318:
317:
316:
315:
310:
305:
297:
296:
292:
291:
290:
289:
284:
279:
274:
266:
265:
263:Mollusc shells
259:
258:
250:
249:
243:
242:
234:
233:
232:
231:
226:
218:
217:
213:
212:
200:
196:
195:
190:
186:
185:
180:
176:
175:
170:
166:
165:
160:
156:
155:
142:
141:
123:Fissidentalium
117:
116:
108:
107:
99:
94:
89:
84:
79:
74:
69:
64:
59:
54:
49:
44:
37:
26:
9:
6:
4:
3:
2:
2451:
2440:
2437:
2435:
2432:
2430:
2427:
2425:
2422:
2420:
2417:
2415:
2412:
2411:
2409:
2392:
2387:
2383:
2379:
2373:
2369:
2364:
2360:
2356:
2351:
2347:
2343:
2338:
2334:
2330:
2324:
2320:
2315:
2311:
2307:
2302:
2298:
2294:
2289:
2285:
2281:
2276:
2272:
2268:
2263:
2259:
2255:
2250:
2246:
2242:
2237:
2233:
2229:
2224:
2220:
2216:
2211:
2207:
2203:
2198:
2194:
2190:
2185:
2181:
2176:
2170:
2166:
2161:
2155:
2151:
2150:
2148:
2146:
2142:
2138:
2133:
2129:
2118:
2114:
2112:
2108:
2106:
2105:Rostroconchia
2102:
2101:
2099:
2095:
2089:
2086:
2084:
2081:
2079:
2076:
2074:
2071:
2069:
2066:
2064:
2061:
2059:
2058:Solenogastres
2056:
2054:
2051:
2050:
2048:
2044:
2040:
2032:
2027:
2025:
2020:
2018:
2013:
2012:
2009:
2003:
2000:
1997:
1993:
1992:
1983:
1979:
1975:
1971:
1970:
1965:
1961:
1960:
1959:
1958:
1954:
1953:
1952:
1951:
1947:
1943:
1939:
1935:
1931:
1927:
1925:9780120261420
1921:
1917:
1913:
1909:
1903:
1902:
1889:
1887:0-07-297814-7
1883:
1879:
1872:
1866:
1861:
1853:
1849:
1845:
1841:
1837:
1833:
1829:
1825:
1818:
1810:
1806:
1801:
1796:
1791:
1786:
1782:
1778:
1774:
1767:
1759:
1746:
1738:
1737:10.3133/pp968
1734:
1727:
1720:(4): 543–550.
1719:
1715:
1711:
1704:
1696:
1692:
1688:
1684:
1680:
1676:
1669:
1661:
1657:
1653:
1649:
1645:
1641:
1637:
1633:
1625:
1617:
1613:
1609:
1605:
1601:
1597:
1593:
1589:
1585:
1581:
1574:
1566:
1562:
1557:
1552:
1548:
1544:
1539:
1534:
1530:
1526:
1522:
1515:
1507:
1505:0-03-056747-5
1501:
1497:
1490:
1488:
1479:
1473:
1469:
1468:
1460:
1452:
1448:
1444:
1440:
1436:
1432:
1428:
1424:
1416:
1414:
1405:
1399:
1395:
1394:
1386:
1378:
1371:
1363:
1356:
1348:
1344:
1339:
1334:
1329:
1324:
1320:
1316:
1312:
1308:
1304:
1297:
1289:
1285:
1280:
1275:
1270:
1265:
1261:
1257:
1253:
1249:
1245:
1238:
1230:
1226:
1222:
1220:9780120261420
1216:
1212:
1208:
1204:
1197:
1189:
1185:
1181:
1177:
1170:
1168:
1163:
1155:
1153:
1149:
1145:
1141:
1137:
1133:
1132:
1127:
1126:
1115:
1112:
1111:helcionellids
1108:
1107:Rostroconchia
1104:
1094:
1093:rostroconch.
1092:
1088:
1087:
1082:
1079:
1075:
1074:kentuckyensis
1073:
1067:
1065:
1064:Mississippian
1058:Fossil record
1040:
1036:
1030:
1026:
1020:
1016:
1015:
1013:Steiner, 1992
1011:
1007:
999:
995:
994:
992:Steiner, 1992
990:
986:
985:
981:
978:
970:
966:
960:
959:Omniglyptidae
956:
950:
946:
940:
936:
932:Steiner, 1991
930:
926:
920:
916:
913:
909:
903:
899:
898:
894:
891:
890:
889:
887:
876:
871:
867:
865:
861:
851:
849:
845:
835:
832:
828:
823:
821:
817:
813:
809:
799:
797:
793:
789:
785:
779:
777:
773:
769:
759:
757:
753:
748:
746:
742:
738:
734:
730:
726:
722:
712:
710:
706:
702:
698:
694:
690:
685:
682:
678:
674:
664:
661:
657:
653:
648:
645:
635:
633:
627:
611:
610:
604:
600:
598:
593:
582:
580:
575:
573:
569:
565:
561:
557:
552:
550:
546:
542:
538:
534:
531:
527:
523:
519:
513:
475:
469:
431:
427:
423:
415:
410:
403:
402:
396:
390:
389:
384:
373:
368:
366:
361:
359:
354:
353:
351:
350:
345:
342:
340:
337:
335:
332:
330:
327:
326:
325:
324:
320:
319:
314:
311:
309:
306:
304:
301:
300:
299:
298:
294:
293:
288:
285:
283:
280:
278:
277:Chiton shells
275:
273:
270:
269:
268:
267:
264:
261:
260:
256:
252:
251:
248:
245:
244:
240:
239:
230:
227:
225:
222:
221:
219:
214:
209:
204:
201:
198:
197:
194:
191:
188:
187:
184:
181:
178:
177:
174:
171:
168:
167:
164:
161:
158:
157:
152:
147:
143:
139:
135:
134:
129:
125:
124:
118:
114:
109:
102:
97:
92:
87:
82:
77:
72:
67:
62:
57:
52:
47:
33:
30:
19:
2144:
2127:
2087:
2053:Caudofoveata
1995:
1973:
1967:
1945:
1907:
1877:
1871:
1860:
1827:
1823:
1817:
1780:
1776:
1766:
1754:|title=
1726:
1717:
1713:
1709:
1703:
1678:
1674:
1668:
1635:
1631:
1624:
1583:
1579:
1573:
1528:
1524:
1514:
1495:
1466:
1459:
1426:
1422:
1392:
1385:
1376:
1370:
1361:
1355:
1310:
1306:
1296:
1251:
1247:
1237:
1202:
1196:
1179:
1175:
1143:
1129:
1123:
1121:
1100:
1091:conocardioid
1084:
1070:
1068:
1061:
1010:Gadilimorpha
989:Entalimorpha
952:Palmer, 1974
929:Fustiariidae
883:
874:
857:
841:
824:
805:
780:
765:
749:
718:
693:diverticulum
686:
676:
670:
649:
641:
628:
624:
607:
588:
576:
564:beachcombers
560:intertidally
553:
540:
521:
517:
473:
429:
426:tooth shells
425:
421:
419:
399:
386:
286:
282:Snail shells
202:
131:
121:
29:
2275:iNaturalist
2169:Wikispecies
2078:Cephalopoda
2037:Classes of
1152:Middle East
1140:shell money
1081:rostroconch
1029:Pulsellidae
998:Entalinidae
939:Gadilinidae
924:– 14 genera
919:Dentaliidae
827:trochophore
768:cephalopods
733:pericardium
597:cephalopods
585:Orientation
579:cephalopods
528:of shelled
422:tusk shells
287:Tusk shells
272:Clam shells
189:Subphylum:
35:Tusk shells
2439:Conchifera
2419:Scaphopods
2408:Categories
2202:Scaphopoda
2189:Scaphopoda
2175:Scaphopoda
2145:Scaphopoda
2088:Scaphopoda
2073:Gastropoda
1969:Zoosystema
1955:Cited by —
1783:: 407072.
1710:Pinnocaris
1158:References
1103:Conchifera
1086:Pinnocaris
1078:ribeirioid
1044:– 2 genera
1034:– 3 genera
1024:– 8 genera
1008:sub-order
1003:– 9 genera
987:sub-order
944:– 3 genera
907:– 3 genera
893:Dentaliida
860:Dentaliida
788:staticonia
784:statocysts
741:homologous
568:sea snails
556:substrates
545:Dentaliida
474:scaphopods
430:Scaphopoda
398:Fossil of
303:Conchology
224:Dentaliida
203:Scaphopoda
193:Conchifera
18:Scaphopoda
1844:0022-2933
1745:cite book
1600:1525-142X
1547:2041-9139
1531:(1): 25.
1144:Dentalium
1118:Human use
1097:Phylogeny
1053:Evolution
1019:Gadilidae
974:– 1 genus
969:Rhabdidae
964:– 1 genus
954:– 1 genus
934:– 1 genus
914:– 1 genus
873:Shell of
796:osphradia
752:nephridia
745:ventricle
705:intestine
697:esophagus
677:captacula
673:tentacles
247:Seashells
169:Kingdom:
163:Eukaryota
2154:Wikidata
2083:Bivalvia
2039:Molluscs
1982:81442755
1934:12094723
1852:84697563
1809:24350268
1695:85124687
1660:14497120
1652:10420163
1608:11710763
1565:31641428
1451:37343813
1443:26487042
1347:16675549
1288:26771527
1248:PLOS ONE
1229:12094723
1148:Natufian
980:Gadilida
864:Gadilida
737:perianal
725:ctenidia
721:auricles
689:bivalves
549:Gadilida
537:infaunal
229:Gadilida
183:Mollusca
179:Phylum:
173:Animalia
159:Domain:
138:Gadilida
128:Gadilida
2160:Q238314
1800:3856133
1616:8936294
1556:6800502
1525:EvoDevo
1338:1472512
1315:Bibcode
1279:4714876
1256:Bibcode
1037:family
1027:family
1017:family
996:family
967:family
957:family
947:family
937:family
927:family
917:family
910:family
900:family
838:Ecology
831:veliger
820:gametes
772:ganglia
743:to the
701:stomach
632:ratfish
616:Anatomy
533:mollusc
216:Orders
199:Class:
2378:512944
2375:uBio:
2342:480061
2326:NZOR:
2254:1SCAPC
1980:
1932:
1922:
1884:
1850:
1842:
1807:
1797:
1693:
1658:
1650:
1614:
1606:
1598:
1563:
1553:
1545:
1502:
1474:
1449:
1441:
1400:
1345:
1335:
1286:
1276:
1227:
1217:
810:, and
703:, and
681:radula
660:oxygen
644:mantle
638:Mantle
621:Shells
592:Shimek
530:marine
518:skáphē
210:, 1862
136:, and
133:Gadila
2386:WoRMS
2363:Plazi
2319:32584
2306:82115
2288:IRMNG
2280:67990
2228:8ZXV9
1978:S2CID
1848:S2CID
1691:S2CID
1656:S2CID
1612:S2CID
1447:S2CID
816:gonad
794:, no
786:with
776:brain
729:heart
656:gills
652:cilia
572:clams
526:class
472:(the
313:Valve
308:Nacre
208:Bronn
2355:8166
2314:NCBI
2301:ITIS
2293:1002
2262:GBIF
2249:EPPO
2241:2688
2210:BOLD
1930:PMID
1920:ISBN
1882:ISBN
1840:ISSN
1805:PMID
1781:2013
1758:help
1648:PMID
1604:PMID
1596:ISSN
1561:PMID
1543:ISSN
1500:ISBN
1472:ISBN
1439:PMID
1398:ISBN
1343:PMID
1284:PMID
1225:PMID
1215:ISBN
1128:and
792:eyes
709:anus
642:The
570:and
522:poús
420:The
414:MHNT
46:PreꞒ
2391:104
2267:276
2236:EoL
2223:CoL
2197:AFD
2184:ADW
1912:doi
1832:doi
1795:PMC
1785:doi
1733:doi
1683:doi
1640:doi
1636:241
1588:doi
1551:PMC
1533:doi
1431:doi
1333:PMC
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1207:doi
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