Taxonomic Implications of the Residual Colour Patterns of Ampullinid Gastropods and Their Contribution to the Discrimination from Naticids

Caze, B., Merle, D., Le Meur, M., Pacaud, J.-M., Ledon, D., and Saint Martin, J.-P. 2011. Taxonomic implications of the residual colour patterns of ampullinid gastropods and their contribution to the discrimination from naticids. Acta Palaeontologica Polonica 56 (2): 329–347. The diversity of residual colour patterns is revealed for the first time in the European fossil Ampullinidae. The colour patterns were studied under Ultraviolet (UV) light in approximately 3100 specimens belonging to 83 species, 12 genera (Ampullina, Globularia, Crommium, Amaurellina, Pachycrommium, Amauropsina, Ampullonatica, Eocernina, Ampullinopsis, Vanikoropsis, Pictavia, and Ampullospira) and three subgenera (Globularia, Deshayesia, and Cernina within the genus Globularia). Forty-six Cainozoic species revealed residual colour patterns and 29 of them, belonging to six genera (Ampullina, Globularia, Crommium, Amaurellina, Pachycrommium, Amauropsina), are described herein as examples representing the entire diversity of the encountered colour patterns. These patterns are most diverse during the Middle Eocene coincident with the period of highest taxonomic diversity of the Ampullinidae. Four basic classes, regarded as containing possible homologous colour patterns in terms of pigments incorporation modalities, are proposed. Class I, a fluorescent wide diffuse area or spiral stripes, occurs in most of the species, while the three others are more peculiar. Class II, fluorescent axial zigzagging stripes, Class III, fluorescent axial to slightly opisthocline stripes or segments, and Class IV, fluorescent patches forming axial segments by coalescence, allow an easy distinction between the genera Globularia, Pachycrommium, and three peculiar species of Ampullina. The bauplan of the colour patterns revealed in Globularia is very similar to that of the single extant species, Globularia (Cernina) fluctuata. This supports the view of previous authors who classified them in the same genus. Furthermore, at the family level, the peculiar residual patterns belonging to classes II, III, and IV have not been observed in naticid gastropods. Thus our results for the Cainozoic fossil record are consistent with the conclusions based on anatomy and feeding habits, namely that ampullinid gastropods, regarded for a long time as belonging to the family Naticidae, constitute a family apart.


Introduction
The ampullinids are represented by numerous Mesozoic and Cainozoic shells. In the European Cainozoic, their shells are particularly common (81 of 93 species listed in worldwide Cainozoic; see Supplementary Online Material (SOM 1, for all SOMs see http://app.pan.pl/SOM/app56−Caze_etal_SOM. pdf) and well preserved, constituting an appropriate material for studies of residual colour patterns. While Ampullinidae were quite diverse in the past, now they are represented by sin− gle species, Globularia (Cernina) fluctuata (Sowerby, 1825), living in marine waters of the Philippines. The ampullinids first appeared in the Late Triassic (genus Falorina from Car− nian of San Cassiano formation; Bandel 2006). In Europe, this group reached its biodiversity optimum during the Middle Eocene (at least 40 European species, particularly in the Paris Basin). Later, the number of species decreased dramatically after the Eocene/Oligocene crisis (only 6 species in the Early Neogene of Europe) and disappeared in the Late Neogene of Europe.
Ampullinid shells display a very similar morphology (Lamarck 1804) to those of the naticids (globose shape, semilunar aperture, generally low spire and flattened suture, absence of ornamentation) and historically most authors (e.g., Deshayes 1864;Cossmann 1888;Wenz 1941;Wrigley 1946;Glibert 1963) have considered ampullinids as belong− ing to the Naticidae. Later, some authors (e.g., Wenz 1941;Wrigley 1946;Glibert 1963), however, proposed for them a separate subfamily Globulariinae (a junior synonym of Am− pullininae) within the family Naticidae, including there also the single living ampullinid species. Recently, Kase (1990) studied the anatomical characters (foot, head, proboscis) of G. (Cernina) fluctuata and stated that the latter should be re− moved from Naticidae and the Ampullospirinae (another ju− nior synonym of Ampullininae Cossmann, 1919) should be moved closer to the family Campanilidae. Kase and Ishikawa (2003a) confirmed these interpretations showing that G. (C.) fluctuata is an algal grazer, while all naticids are shell− drilling predatory gastropods. Thus, they removed the entire subfamily Ampullospirinae from Naticidae, indicating also their diagnostic shell characters (spire, columellar lip, proto− conch). Aronowsky and Leighton (2003) criticised this view, basing their discussion on variation of the diagnostic shell characters and disagreed with Kase and Ishikawa (2003a) on the removal of all fossil ampullinids from Naticidae. In their answer to Aronowsky and Leighton (2003), Kase and Ishi− kawa (2003b) indicated that they used a "combination of shell characters" in order to justify this removal. We agree with Aronowsky and Leighton (2003) that further study of the morphology of the ampullinids should be the best way to clarify the higher level taxonomic affiliation of fossil ampul− linid taxa. Therefore, we present an overview of the residual colour patterns of the Cainozoic ampullinids as an additional and here to date unexploited suite of shell characters useful for delimitation of Ampullinidae from Naticidae. Our aim is to demonstrate the diversity of the residual colour patterns; an exhaustive revision and a cladistic analysis of the family Ampullinidae will be published elsewhere. As many ampul− linid species have similar colour patterns, we illustrate the most representative species (including the type species) and those with a large number and/or the best preserved speci− mens; other species are considered in the SOM 1 and SOM 2.

Material and methods
We examined a large number of specimens belonging to 83 ampullinid species (including the sole extant species; see SOM 2) stored mainly in the MNHN. The studied material represents about 3100 specimens from 113 fossiliferous sites of the European, mainly French, Mesozoic and Cainozoic (from the Middle Jurassic to the Middle Miocene). Sixty− nine of 81 species listed in European Cainozoic are present in Paris and Aquitaine basins, Loire−Atlantique, Cotentin, Alpes and Aude (France). No residual colour pattern was re− vealed by the exposure of Mesozoic shells (10 species) under UV light. Forty−six of the 72 Cainozoic species showed re− sidual patterns.
The residual shell pigmentation may be revealed or en− hanced by bleaching specimens in sodium hypochlorite (NaClO) then directly exposing those under long−wave UV light (Olsson 1967;Vokes and Vokes 1968;Krueger 1974;Hoerle 1976;Dockery 1980;Swann and Kelley 1985;Pitt and Pitt 1993;Kase et al. 2008). For the UV light observa− tion, the samples were processed using the procedure defined by Merle et al. (2008): (i) they were placed in a bath of con− centrated sodium hypochlorite for 24 hours; (ii) they were carefully washed with water to eliminate all traces of dried hypochlorite of sodium; (iii) most of the patterns were re− vealed by exposure under UV light emitting a wavelength of 3600 Å (Merle 2003). For the UV light photography, the specimens were placed at the intersection of the beams of two UV lamps arranged face to face and emitting the same wavelength. Finally, in order to get the best images, we have undertaken software processing (brightness and contrast ad− justment). The photographed specimens are presented as im− aged under UV light and not in negative view. Comments on the relationship between colouration and pig− mentation: We observed that the fluorescent regions re− vealed under UV light on fossil shells correspond to regions with residual pigmentation and that dark regions correspond to "unpigmented" regions. In most cases Recent shells show an inverted contrast: the pigmented regions appear dark and the unpigmented regions appear pale or white. Nevertheless, the shells of Globularia appear to present an exception: anal− ogous axial zigzagging stripes observed in several species appear fluorescent, and consequently pigmented, in the fossil record while they are white on the Recent shells. Without chemical analyses, we are unable to determine whether this absence of contrast reversal between the fossil and extant species results from an arrangement of pigments producing a "white colour" in the extant one or from the non−homology of the similar fossil and Recent axial zigzagging stripes. Con− sequently, we do not know if the use of negative views would permit the observation of colour patterns as they "would have appeared in life" (Hendricks 2009) and prefer to keep the true appearance of the colour patterns as observed under UV light.

Descriptive terminology
Number of levels of residual colouration: the patterns can show from 2 to 4 different colours, called by Meinhardt (1998), levels of pigmentation. Background relative colouration: a darker or paler back− ground contrasts with the elements producing the different patterns. Background colour zonation (Fig. 1A): the background can show diffuse colour variations, forming generally some broad stripes or area. Stripes (Fig. 1B, C): this term applies to any elongated fluo− rescent colour pattern component which is axially or spirally continuous on the whole shell. "Stripes" (Fig. 1D, E): the use of quotes illustrates the desire to distinguish the result of a lack of fluorescence from well delineated fluorescent stripes. Patches (Fig. 1F): this term applies to any small area of a col− our contrasting sharply with the background. Segments (Fig. 1G): the segments are short elongated sec− tions, generally resulting from the coalescence of patches. They are always axially elongated in ampullinids.
Colour pattern description.-The pattern consists of three levels of residual colouration. The background is heteroge− neous with a fluorescent spiral stripe located just below the subsutural step ( Fig. 2A 1 ). The apex is paler. The diffuse stripe varies in breadth and the whorl is sometimes almost entirely fluorescent (excepting the subsutural step and the base). In the latter case, the stripe may have a different colour (more orange) and is still distinguishable. An additional thin median stripe is seen ( Fig. 2A 2 ) in several specimens.
Ampullina parisiensis (d'Orbigny, 1850) Colour pattern description.-The residual pattern is variable and consists of three levels of residual colouration. The back− ground is heterogeneous with one ( Fig. 2B, C 1 ) or two fluo− rescent spiral stripes and the apex is pale (Fig. 2C 1 ). The tran− sition between the two levels of residual colouration of the background is diffuse. There are usually two fluorescent stripes: a broad one on the adapical part and a thinner one on the adbasal part ( Fig. 2C 2 ). The width of the adapical stripe varies among specimens. Sometimes there are two thin ad− basal stripes very close to each other instead of one. The adbasal stripe is sometimes absent and several specimens have an additional thin subsutural fluorescent stripe. Some specimens display a single broad stripe spreading on the ma− jor part of the whorl. Although the whorl could be almost en− tirely fluorescent (excepting the subsutural step and the base), the adapical stripe is sometimes in a different colour (more orange) and remains distinguishable.
Comments on the residual colour pattern of A. depressa depressa and A. parisiensis.-Several hypotheses can be ad− vanced to explain the occurrence of two different colours in the background fluorescence: (i) the chemical nature of the incorporated pigments; (ii) the concentration of the incorpo− rated pigments; (iii) the modalities of incorporation. The first two hypotheses appear plausible. Previous studies, chro− matographic (Comfort 1949a(Comfort -c, 1950(Comfort , 1951Nicholas and Comfort 1949) and spectrometric (Hedegaard et al. 2006) analyses, have indeed revealed differences in the nature of the substances involved in the pigmentation of gastropod shells. Moreover Hedegaard et al. (2006) also indicated that there is no simple relationship between pigment, colour and taxa: different colours within a single taxon may be due to different pigments or different saturations of colour can be generated by different concentrations of the same pigment.
Ampullina rustica (Deshayes, 1864)  Colour pattern description.-The shells show three levels of residual colouration. The background is heterogeneous with a dark subsutural step and a wide fluorescent area covering the major part of the whorl (Fig. 2D 2 ). The apex is pale. The tran− sition between the fluorescent area and the darker area of the background is mostly diffuse. The absence of fluorescence on the subsutural step induces a dark straight spiral "stripe" (Fig.  2D 1 ). The base of the whorl may be dark too. Sometimes, there are also slightly darker thin and diffuse spiral "stripes" on the last whorl due to a localized lack of fluorescence. These "stripes" are related to obsolete spiral "microlines" and their number and distribution are variable. The residual colour pat− tern is very similar to that of A. grossa (Deshayes, 1864) from the Lutetian-Bartonian of the Paris Basin (Fig. 2E). Colour pattern description.-The pattern consists of three levels of residual colouration. The background is heteroge− neous with three fluorescent spiral stripes (Fig. 2G, H) and the apex is pale. The transition between the two levels of re− sidual colouration of the background is diffuse. These stripes are located on the shoulder and on the median and adbasal parts of the whorl. Their thickness is not homogeneous on the shell and varies among specimens (Fig. 2G, H 1 ).

Ampullina chenayensis Cossmann, 1892
Comments.-The figured shells (Fig. 2G, H) are from the Thanetian of Bachivillers (France, PB) from where this spe− cies' occurrence has never been listed. However their shell shape, oblong with slightly elevated and turreted spire and tabulate whorls, differs obviously from the sole previously known Thanetian species A. chenayensis ( Fig. 2F) which is globose with a low spire and lacks tabulate whorls. We con− sider that our specimens display the characteristic morphol− ogy of the Cuisian species A. aizyensis and that they repre− sent the oldest known occurrence of this species.
Ampullina stampinensis (Cossmann and Lambert, 1884)  cent stripes (Fig. 2I). The transition between the two levels of colouration is diffuse. The stripes are located on the adapical part, median part and adbasal part of the whorl. Their width is almost equal in the youngest specimens, but the median one becomes broader in most adult specimens. Some young specimens display a fourth spiral stripe around the umbilicus on the base of the shell.
Ampullina perusta (Defrance in Brongniart, 1823) Colour pattern description.-The pattern consists of two levels of residual colouration: a pale heterogeneous back− ground with several dark spiral stripes. Sometimes, there is only a group of two or three thin stripes very close to each other, of a variable width (Fig. 2J), on the median part. There is sometimes an additional broad adapical stripe (Fig. K).
Comments.-The residual colours in this species are observ− able in natural light and are obviously different from those of the other species. This is the result of a different type of pres− ervation of the colour pattern. It is also interesting to note that this pattern appears as the negative of the residual colour pat− tern on the other shells and that the dark elements in this spe− cies correspond to the fluorescent ones in UV light observa− tions.
Ampullina intermedia (Deshayes, 1832)  Colour pattern description.-The pattern consists of four levels of residual colouration. The background is heteroge− neous with three spiral slightly fluorescent stripes, one on the adapical part, one on the median part and one on the adbasal parts of the whorl (Fig. 3A). The apex is pale and there are small fluorescent patches superimposed on the background ( Fig. 3A-C). The transition between the levels of colouration of the background is diffuse. The background is homoge− neously dark in some specimens ( Fig. 3B-E). The small patches of varying size do not have a definite shape and their distribution is irregular (Fig. 3B). The coalescence of the patches sometimes produces fluorescent sinuous axial seg− ments (Fig. 3D, E). This residual colour pattern is very simi− lar to those of A. merciniensis (Deshayes, 1864) (Fig. 3F) from the Ypresian (Cuisian) of the Paris Basin and Ampul− lina lignitara (Deshayes, 1864) from the Ypresian (Spar− nacian) of the Paris Basin and Hampshire Basin.
Comments.-Former authors (Cossmann 1888;Wrigley 1946;Glibert 1963) considered the three species Ampullina intermedia (Deshayes, 1824), A. lignitara (Deshayes, 1864) and Ampullina merciniensis (Deshayes, 1824) as belonging to the genus Crommium. In the original description of the ge− nus, Cossmann (1888) however stated, that the sheath is ab− sent whereas it occurs in each of the three aforementioned species. Thus, A. intermedia, A. lignitara, and A. merci− niensis are, here, no longer considered to belong to the genus Crommium. Furthermore, these species with closely related 334 ACTA PALAEONTOLOGICA POLONICA 56 (2), 2011  shells, display very similar residual patterns. Consequently, our personal opinion is that the discrimination of these three species is probably not justified.

Genus Globularia Swainson, 1840
Type species: Globularia sigaretina (Lamarck, 1804), Grignon, Lutetian. Description.-This genus is here considered to comprise three subgenera (Globularia, Deshayesia, and Cernina) with 20 species (16 Palaeogene species, 3 Neogene and one extant; SOM 1). The taxa Globularia, Cernina, and Deshayesia have not always been regarded as congeneric (Wrigley 1946). Nev− ertheless, the very similar residual colour patterns of 11 of the 15 studied species (zigzagging axial fluorescent stripes; SOM 2; Fig. 4, 5) strengthens the initial impression based on the shell morphology (wide aperture with prosocline outer lip, low spire and expanded sheath delineated by a rim) that they are closely related (Cossmann and Peyrot 1919;Wenz 1941). Thus, thanks to the additional character, all these species are, here, no longer considered to belong to distinct genera but are placed within the genus Globularia (senior synonym).

Subgenus Globularia Swainson, 1840
Globularia ( (Fig. 4M). The axial thin stripes pres− ent a regular distribution. The zigzags occur along the whole height of the stripes and display variable amplitude. There is intraspecific variability in the number and density of the ax− ial thin stripes. This residual colour pattern is very similar to those of Globularia (G.) splendida (Deshayes, 1864) from the Ypresian of the Paris Basin (Fig. 4N) and Globularia (G.) patuloides (Cossmann, 1902) from the Bartonian of the Paris Basin (Fig. 4O).
Globularia (Globularia) peyreirensis (Cossmann and Peyrot, 1919)  Colour pattern description.-The colour pattern consists of three levels of residual colouration: a dark and homogeneous background, a pale apex and some thin fluorescent axial stripes forming zigzags (Fig. 5B 2 , C). The axial thin stripes are not parallel and present an irregular distribution. The zig− zags occur along the whole height of the stripes and display variable amplitude. There is intraspecific variability in the density of axial stripes (Fig. 5B 2 , C 2 ).
Comments.-?Globularia pilula has been previously classi− fied in the naticid genus Euspira. These shells strongly differ from the type species of the latter genus, Euspira glaucinoides (Sowerby, 1812) from the Ypresian of England, in many char− acters (moderately high and acuminate spire, sutural step, minute umbilicus with no sheath and narrow reflected colu− mellar edge). Furthermore, the colour pattern differs from those of the fossil naticid shells by converging stripes and nu− merous zigzags with very variable amplitude as observed in the characteristic colour pattern of genus Globularia. Thus, this species is, here, excluded from Euspira and is placed within the family Ampullinidae, but only questionably placed in the genus Globularia, because of its lack of a sheath.
Subgenus Cernina Gray, 1842 Colour pattern description.-This species shows two levels of residual colouration (apex absent). The background is dark and homogeneous. There are thin axial fluorescent stripes. The thin axial stripes are very close to each other, but not parallel and form small zigzags (Fig. 5F 1 , G). Their distri− bution on the shell is variable (Fig. 5G) and the zigzags dis− play variable amplitude. The stripes sometimes branch in a dichotomous manner (Fig. 5F 2 ).
Globularia (Cernina) sp. Comments.-All three specimens from Saint−Martin−d'Oney (France, AB) display the characteristic morphology of Glo− bularia (Cernina) compressa but the coloured pattern differs by the presence of opisthoclines, barely sinuous, thin stripes instead of axial zigzagging stripes (Fig. 5F, G). In our view, these differences do not result from intraspecific variability and justify these shells as belonging to a species other than G. (C.) compressa.
Crommium acutum (Lamarck, 1804)  Colour pattern description.-The shells show three levels of residual colouration. The background is heterogeneous with a fluorescent area covering the apical part of the whorl (Fig.  6A, B) (except a thin zone just below the suture). The apex is pale. The transition between the two levels of colouration of the background is diffuse. There is sometimes a second fluo− rescent diffuse area on the base of the shell. These fluores− cent areas cover a smaller or larger part of the whorl. The largest specimens show an entirely fluorescent last whorl (except the subsutural part). The young specimens display three or four thin spiral fluorescent stripes: one on the shoul− der, one on the base (but often lacking) and two on the me− dian part of the whorl (Fig. 6C). The two median stripes fade with growth until they disappear. The adapical one and the basal one, when present, gradually spread on the whorl.

Genus Amaurellina Bayle in Fischer, 1885
Type species: Amaurellina spirata Lamarck, 1804, Grignon, Lutetian. Description.-Worldwide, this genus comprises 8 species in the Cainozoic (SOM 1). 5 of the 6 studied species (SOM 2) display the same simple organisation of residual colouration with one or several fluorescent spiral stripes on a darker background.
Amaurellina spirata Lamarck, 1804 The background is heterogeneous with an almost completely dark whorl except the slightly flu− orescent shoulder that forms a spiral stripe (Fig. 7A-C). The apex is pale ( Fig. 7A-C). The fluorescent stripe covering the subcarinate shoulder is straight and has a constant width (Fig.  7A 1 , C). This stripe is sometimes also observable on the pen− ultimate whorl (Fig. 7C). The transition between this stripe and the darker colouration of the whorl is diffuse. The base of the whorl can be slightly fluorescent too.
Amaurellina levesquei (d'Orbigny, 1850) Colour pattern description.-The shells show two levels of residual colouration: a heterogeneous background with a slightly fluorescent area covering the major part of the shell (apex, spire, last whorl) except two dark "stripes". The ada− pical one is on the median part of the whorl and is thinner than the other one located on the base of the shell (Fig. 7D, E). On a few well−preserved shells, some slightly fluorescent axial stripes are distinguishable (Fig. 7F). These axial stripes, espe− cially distinguishable on the spire, are slightly prosocline.
Amaurellina sinuosa (d'Orbigny, 1850) fluorescent spiral stripes (Fig. 7J 1 ): one is located on the subsutural part of the whorl, one is on the base, circling the umbilicus, and two are on the median part. These stripes pres− ent a similar and constant width and are slightly thinner than the space between. The two adapical stripes are sometimes distinguishable on the penultimate whorl. This residual colour pattern is very similar to that of Amaurellina tuba (Deshayes, 1864) from the Lutetian of the Paris Basin (Fig. 7L).
Pachycrommium suessoniensis (d'Orbigny, 1850)  levels of residual colouration. The background is dark and homogeneous, the apical whorls appear paler than the rest of the spire but are rarely preserved and there are some axial flu− orescent stripes (Fig. 8A, B). The axial stripes, straight to sin− uous and slightly prosocline (Fig. 8A 1 , B 2 ), are only observ− able on the spire. The width of the stripes is equivalent to that of their interspaces and their distribution is regular. This re− sidual colour pattern is very similar to those of Pachy− crommium productum (Deshayes, 1864) from the Lutetian of the Paris Basin (Fig. 8C), Pachycrommium sp. from the Ypresian of the Paris Basin (Fig. 8D) and Pachycrommium hybridum (Lamarck, 1804) from the Bartonian (Auversian) of the Paris Basin.
Pachycrommium scalariformis (Deshayes, 1825)  Colour pattern description.-The colour pattern consists of a dark and homogeneous background and broad axial slightly fluorescent stripes (Fig. 8E, F). These stripes appear straight on the spire but present saw−tooth edges. They actually form zigzags spreading over the whole height of the whorl. Their width is not constant (Fig. 8F).
Pachycrommium acuminatum (Lamarck, 1804)  Colour pattern description.-The pattern consists of three levels of residual colouration. The background is dark and homogeneous, the apex is pale and there are broad axial fluo− rescent stripes (Fig. 9I, J, K 3 ). The stripes are broader than the interspaces and their width increases with growth ( Fig.  9I 2 ). Their distribution is regular and they may be straight (Fig. 9I 1 ) or sinuous (Fig. 9J 1 ). Some specimens from Dax (Fig. 9J, K) display an additional level of colouration: some patches much darker than the background, more or less axi− ally compressed, with irregular distribution and often coales− cent (Fig. 9J  Description.-No residual colour pattern is observed under UV light. Remarks.-This genus comprises 5 worldwide Cainozoic species (SOM 1). Two of the studied species of Ampullo− natica, A. ambulacrum (Sowerby, 1822), and A. brongniarti (Deshayes, 1864) from the Bartonian of England and France (HB, PB; SOM 2), are characterised by an acuminate and moderately high spire turreted by a deeply canaliculated su− ture, a large and deep umbilicus with an undistinguishable sheath and a thin and narrow columellar edge. This shell morphology is similar to the shell morphology of the enig− matic taxon Amauropsina.
?Ampullonatica gouberti (Deshayes, 1864), described on the basis of a unique specimen from the Bartonian of France, displays unusual shell morphology (very strong shoulder, very low spire) and might be a teratological specimen of an already known species (e.g., Ampullina parisisiensis).
Description.-The two Palaeogene species of this genus (SOM 1, 2) display various morphologies of the colour pat− tern varying from fluorescent patches more or less regularly positioned on a darker background to axial fluorescent seg− ments formed by coalescence of these patches.
Remarks.-The morphology of the species of Amauropsina (elevated and acuminate spire, large umbilicus without sheath, narrow columellar edge somewhat reflected and, in the type species a narrowly canaliculated suture) is not repre− sentative of the Naticidae. This rather resembles the shell morphology of the ampullinid genus Ampullonatica (no re− sidual pattern under UV light). However, the colour pattern of A. arenularia is similar to that revealed in Eocene naticids (Le Meur 2009) and that of A. canaliculata displays sparse small fluorescent patches, unknown from other naticids and even from other ampullinids. Interpretations of the system− atic affinity of this genus derived from shell morphology and colour pattern data differ and so the genus Amauropsina re− mains an enigmatic taxon.
Amauropsina canaliculata (Lamarck, 1804)  Colour pattern description.-This species exhibits three lev− els of residual colouration. The background is dark and ho− mogeneous. The apex is pale and there are three spiral rows of fluorescent patches. The patches are variable in shape and they are axially and spirally aligned (Fig. 10E). A specimen from Saffré (Loire−Atlantique) displays some sinuous axial segments (Fig. 10F). Depending on the part of the shell, there may be only axial elongated sinuous segments or alternating elongated and short straight segments (Fig. 10F 2 ). In the lat− ter case the two types of segments are sometimes connected (Fig. 10F 3 ).

Discussion
Classification of the ampullinid colour patterns.-The different residual colour patterns can be organised into four distinct classes, each containing possible homologues in re− gard to the modalities of pigments incorporation during shell growth: -one to three spiral stripes or a wide fluorescent diffuse area (colour zonation of the background); -axial fluorescent zigzagging stripes; -axial, sometimes opisthocline, straight or slightly sinuous stripes or segments; -fluorescent patches sometimes forming axial segments through coalescence. Class I contains the most common patterns (Figs. 2-7) within the Ampullinidae and occurs in most of the genera ex− cept Pachycrommium (Figs. 8,9). The survey of a large num− ber of specimens, particularly in the genera Ampullina and Crommium, shows that spiral stripes can diffuse and spread through ontogenesis, thus forming a wide diffuse area. We therefore include these two colour patterns in Class I. We be− lieve that they both result from variation of the background colouration.
The three other Classes: II (Globularia including the ex− tant species), III (Pachycrommium), and IV (three species of Ampullina) are easily distinguishable and occur less com− monly within the Ampullinidae.
Taxonomic implications of the patterns.-Class I: The re− sidual patterns of this class are very common within the Ampullinidae and also in numerous superfamilies of gastro− pods (e.g., Caenogastropods: Naticoidea, Cerithioidea, Litto− rinoidea, Muricoidea, Triphoroidea, Epitonioidea, Conoidea; Heterobranchia: Pyramidelloidea). They also occur in the Re− cent terrestrial Ampullarioidea, that have very similar overall shell morphology. As a corollary we regard them as general within the Ampullinidae and, whether plesiomorphic or result− ing from convergence, they do not appear to be systematically informative. Consequently, in this case, the residual patterns of the Class I do not reliably discriminate ampullinid gastro− pods from naticids, although this pattern morphology is rarely encountered in fossil Naticidae (Le Meur 2009). Some spe− cies, e.g., Globularia (G.) patula (Lamarck, 1804) and Amau− rellina sinuosa (d'Orbigny, 1850), display sharply delineated spiral stripes, which never diffuse with growth. Thus, these peculiar stripes do not appear as a result from variation of the background. They might be real elements of pattern, as in the Recent helicid land snail Cepaea nemoralis (Linnaeus, 1758). In this case, there would be a transition from background vari− ation to real elements of patterns in the genera Globularia and Amaurellina.
Class II: All the species of Globularia, excepting Globu− laria (G.) patula, reveal patterns of Class II, alone or super− imposed on a pattern of Class I (Figs. 4, 5). The absence of this pattern in the other genera of the family makes us con− sider it as probably more derived. Thus the striking similarity of the pattern between the various fossil species of Globu− laria (Figs. 4,5) and with the sole extant species, G. (Cerni− na) fluctuata, suggests a close relationship. This type of thin axial fluorescent zigzagging stripes is absent in naticids ( Fig.  11; Table 1) allowing an easy distinction of all the species of Globularia from those of the Naticidae and supporting their inclusion to Ampullinidae.
Class III: Our observations demonstrated that the species of Pachycrommium reveal similar patterns of Class III (Fig.  8, 9). This class of pattern is absent in all other Ampullinidae with the exception of rare specimens of Amaurellina leves− quei. Thus this character, almost unique to Pachycrommium, can be regarded as a second probable derived pattern within the Ampullinidae suggesting a certain unity within this ge− nus. Furthermore, this class of pattern is never observed in Naticidae and allows this genus of Ampullinidae to be distin− guished from the Naticidae. Besides, the similarity between the pattern morphology of P. acuminatum and G. (Cernina) sp. indicates that both genera, Pachycrommium and Globu− laria, seem phylogenetically not very distant.
Class IV: Three species of Ampullina (Ampullina. inter− media, A. merciniensis, and A. lignitara; Fig. 3) display fluo− rescent poorly organised elements and sometimes thin sinu− ous axial segments. Among the studied taxa, this pattern is more similar to the peculiar pattern of the Class II of Globu− laria than any other known from the other genera. This sug− gests that Ampullina and Globularia seem phylogenetically not very distant too.

Conclusions
The study of the residual colour patterns provides much new morphological information on fossil Cainozoic species of the family Ampullinidae. The testing on Mesozoic species pro− vided up to now only negative results. Future observations of very well preserved material (e.g., Cretaceous from Northern America, Jurassic from Eastern Europe) nevertheless may complete the present study. The diversity of Cainozoic colour patterns appears to a greatest magnitude during the Middle Eocene, when the specific richness of the family is most pro− nounced, as observed in the stromboid family Seraphsidae (Caze et al. 2010).
Firstly, we demonstrated that there is an obvious similarity between the residual pattern of fossil Globularia and that of the extant Globularia (Cernina) fluctuata. Secondly, in the other studied genera, some species display intermediate pat− terns suggesting a transition between Globularia and Ampul− lina (A. intermedia; Fig. 3) and between Globularia and Pachycrommium (Globularia (C.) sp.; Fig. 5).
Otherwise the colour patterns of fossil ampullinids and naticids appear easily distinguishable (Le Meur 2009;Fig. 11) and can be used as an additional diagnostic character to discriminate the two families (Table 1). Thus, although the request of Aronowsky and Leighton (2003) for more detailed morphological studies was correct, we can safely confirm the suggestion of Kase and Ishikawa (2003a) that fossil, or at least Cainozoic, and Recent ampullinids should be removed from Naticidae. Nevertheless, we should urge caution be− cause the species with the general colour pattern of class I are difficult to adjudicate. Finally, we believe that molecular se− quence data analyses would be helpful to resolve this ques− tion definitively and thus test the relevance of the use of UV light in such cases. Despite the existence of only a single liv− ing representative, we can assert that the colour patterns of Globularia remain almost unchanged from the Early Palaeo− gene to the Recent, the other patterns disappearing with the extinction of the other ampullinid genera.  Kase 1990, andKase andIshikawa 2003a) supplemented with colour pattern features (this paper).

Ampullinidae
Naticidae Feeding habits Algal grazer Carnivorous predator Anatomical features foot with small, flat, quadrangular propodium and massive, short metapodium; -wide, flat, bipartite and snoutless head without extensible proboscis -foot with a large plow−like propodium; -head with a long extensible proboscis con− taining the radula Morphological featureshighly elevated and pointed spire; -tabulate whorls; -columellar lip lined abaxially with a sheath; -anterior tip of the columellar lip often expanding abaxially into a round lobe; -species with small protoconch have protoconch consisting of 1.2-1.5 helicoidal, smooth and inflated whorls.
low spire with obtusely pointed apical whorls; -devoid of a sheath and developing instead one or more funicles; -species with small protoconch have protoconch consisting of 2.2-3.5 planispirally and ornamented whorls.