Allmonia, Harzhauser & Landau, 2019

Harzhauser, Mathias & Landau, Bernard, 2019, Turritellidae (Gastropoda) of the Miocene Paratethys Sea with considerations about turritellid genera, Zootaxa 4681 (1), pp. 1-136 : 85-87

Genus Allmonia new gen.

New name for Proto de Blainville, 1824 non Leach, 1814.

Proto de Blainville, 1824: 228 , non Proto Leach (1814: 353) [Crustacea].

Hemitropis Handmann, 1882: 212 , non Hemitropis Fieber (1866: 499) [Insecta].

Type species. Turritella cathedralis Brongniart, 1823 . Early Miocene, Léognan at Bordeaux, France, Aquitaine Basin (see discussion on the taxonomic status and type locality below) .

Diagnosis. Medium-sized to very large; moderately slender to very slender shells, typically with flat sided early and middle teleoconch sided whorls. Adult whorls and last whorl flat sided, concave and/or telescoped. Suture weakly incised or insignificant. Highly variable spiral sculpture on early teleoconch whorls in all species, tends to fade out on adult whorls. Spiral sculpture at adapical suture often forming subsutural collar or carina. Lateral sinus wide, simple concave with maximum depth around mid-whorl passing via prominent inflection point at basal angulation into basal sinus. Adapical part of lateral sinus steeply or moderately prosocline, lower part weakly opisthocline to nearly straight. Lateral sinus angle typically ranging around 16–28°. Transition into base coinciding with marked angulation and spiral cord, adjoined by spiral groove between angulation and fasciole. Fasciole broad, prominent, often scalloped by growth increments. Aperture wide, with flaring, often thickened, blunt outer lip. Inner lip narrow, reflected, well demarcated from base, passing into glossy parietal callus. Basal sinus deep to very deep, moderately wide. Short, weakly twisted canal. No inner lirae.

Etymology. In honor of Warren D. Allmon (Paleontological Research Institution, Ithaca, USA), specialist on turritellid gastropods.

Included species. North Sea: Allmonia woodi ( Speyer, 1869) ; Rupelian ( Germany, the Netherlands, Belgium), Allmonia schwarzbachi ( Strauch, 1967) : Chattian ( Germany) ( Anderson 1960; Strauch 1967; R. Janssen 1978; Marquet et al. 2016). North-eastern Atlantic: Allmonia cathedralis ( Brongniart, 1823) (including subjective junior synonyms as listed below): early Miocene (Aquitanian, Burdigalian) to middle Miocene (Langhian), north-eastern Atlantic ( France). Allmonia vasconiensis ( Cossmann & Peyrot, 1922) , A. inaequiplicata ( Cossmann & Peyrot, 1922) , A. turoniensis Glibert, 1949 : middle Miocene (Langhian), Loire Basin ( France) ( Peyrot 1938; Glibert 1949) [status unclear; may be related to A. cathedralis ]. Allmonia densecingulata ( Cossmann & Peyrot, 1922) : middle Miocene (Langhian), north-eastern Atlantic ( France). Allmonia mutabilis Sowerby, 1847 ): early Miocene (Burdigalian) to late Miocene (Tortonian), Portugal. Allmonia rotifera ( Lamarck, 1822) : early Miocene (Burdigalian) to late Miocene (Tortonian), Portugal. Proto-Mediterranean Sea: Allmonia alterniplicata ( Sacco, 1895) (including subjective junior synonyms as listed below): early Oligocene (Rupelian) to late Oligocene Chattian), northern Italy. Allmonia funiculata ( Borson, 1821) (including subjective junior synonyms as listed below): early Miocene (Burdigalian), northern Italy. Allmonia rotifera ( Lamarck, 1822) : late Miocene (Tortonian), Italy, S-France. Western and Central Paratethys: Allmonia quadricanaliculata ( Gümbel, 1861) : Egerian (late Oligocene and/or early Miocene) of Bavaria ( Wolff 1897), Croatia ( Anić 1952) and Hungary ( Báldi 1973) [status unclear]. Allmonia paucicincta ( Sacco, 1895) (including subjective junior synonyms as listed below): early Miocene (Eggenburgian), Switzerland, Germany, Austria, Hungary, Slovenia, Czech Republic. Allmonia inaequiplicata ( Cossmann & Peyrot, 1922) : middle Miocene (Badenian), Austria, Hungary. Allmonia carniolica ( Stache, 1858) (including subjective junior synonyms as listed below): early Miocene (Karpatian) and middle Miocene (Badenian) of Central Paratethys ( Slovenia, Austria, Hungary). The Egerian Turritella diversicostata Gümbel, 1861 , which is placed in Protoma by Báldi (1973), is probably not a Protominae . Eastern Paratethys: One species was mentioned by Popov (1986) as Protoma cathedralis quadricincta Schaffer from the Tarkhanian (late early Miocene to early middle Miocene) of the northern Talysh in Azerbaijan. Indian Ocean: Turritella deshayesi d’Archiac, 1850 : early Miocene (Aquitanian, Burdigalian), Pakistan (Baluchistan), NW-India (Kutch) (Harzhauser et al. 2009a). In addition, several species from the Oligocene and early Miocene of northwestern India and Pakistan may belong to Allmonia (e.g. Turritella renevieri d’Archiac & Haime, 1853 , Protoma retrodilatatum Vredenburg, 1928 , Protoma subrenevieri Vredenburg, 1928 , Protoma sindiense Vredenburg, 1928 ). Some doubts remain, as no apertures are known from these species. Similarly, the placement of Turritella eudeli Cossmann, 1910 ( Cossmann 1910a) from the Pliocene of Karaikal (south-eastern India) in Allmonia , as proposed by Cossmann (1912) (as Protoma ), is doubtful due to its fragmentary preservation.

Geographic range. North Sea ( Germany, the Netherlands, Belgium), Northeastern Atlantic ( Portugal, France), Proto-Mediterranean Sea ( France, Algeria, Italy, Greece, Turkey, Iran), Western and Central Paratethys (Switzer- land, S-Germany, Austria, Hungary, Czech Republic, Slovakia, Slovenia, Bosnia and Hercegovina, Bulgaria), Indian Ocean ( Pakistan, NW-India). A record of Protoma (= Allmonia ) from the Burdigalian of the tropical eastern Atlantic ( Angola) by Dartevelle et al. (1954) will need verification.

Stratigraphic range. Early Oligocene (Rupelian) (e.g. Rovereto 1900) to late Miocene (Tortonian) (e.g. Bernasconi & Robba 1993). Eocene records mentioned by Rumi et al. (1973) are most probably based on misidentifications.

Paleoenvironment. The Paratethyan Allmonia paucicincta ( Sacco, 1895) is found in large numbers in sandy littoral to shallow sublittoral settings of an agitated coast fringed by numerous small crystalline islands ( Pervesler et al. 2011). Similarly, the north-eastern Atlantic Allmonia cathedralis ( Brongniart, 1823) and the Paratethyan Allmonia carniolica ( Stache, 1858) are associated with shallow marine taxa ( Lozouet et al. 2001; Mikuž 2009). The Proto-Mediterranean Allmonia rotifera ( Lamarck, 1822) is described from shallow sublittoral environments of 0–25 m water depth from the Tortonian of northern Italy by Bernasconi & Robba (1993), being eponymous for the ‘ Protoma rotifera community’.

Separation from Protoma Baird, 1870 . The species here included in Allmonia have been treated as Protoma in the paleontological literature (e.g. Sacco 1895, 1896; Vredenburg 1928; Lozouet et al. 2001; Harzhauser et al. 2009a; Mikuž 2009). The type species of Protoma is the extant Protoma knockeri Baird, 1870 from Western Africa by monotypy. Herein, we illustrate three of the six syntypes of the extant Protoma knockeri from Whydah (west coast of Africa), which are stored in the Natural History Museum in London (NHMUK 1870.1.14.19). The largest syntype attains 55.5 mm in height and 15.1 mm in width ( Figs 23A 1 –A 2 ). The other two illustrated syntypes attain 49.1 mm in height and 13.2 mm in width ( Figs 23B 1 –B 2 ) and 31.1 mm in height and 8.2 mm in width ( Figs 23C 1 – C 2 ); pictures copyright of the NHMUK, taken by Kevin Webb, provided by Andreia Salvador, both NHMUK). Thus, Protoma knockeri is considerably smaller than the Oligocene to Miocene species of Allmonia . Aside from the smaller size, Protoma differs from Allmonia in its much weaker fasciole, and the deep and narrow basal sinus ( Figs 24 A–B versus 24 C–D). It lacks the prominent basal angulation of the last whorl, the marked concavity between angulation and fasciole and the broad parietal callus, which are typical for Allmonia . Further, it has a straight sided and thin outer lip, which differs from the flaring and thickened lip of Allmonia . It is worth mentioning, that Baird (1870) explicitly did not include the fossil European species in his Protoma .

Remarks. The first genus name proposed for some of the species united herein in Allmonia was Proto . This name was introduced as name for a Turritellidae genus in 1824 on page 228 in volume 32 of the ‘Dictionnaire des Sciences Naturelles’. As indicated in the preface, all mollusc-paragraphs in the ‘Dictionnaire’ were written by M. de Blainville, whereas geological chapters were provided by M. Brongniart, M. Brochant de Villiers, and M. Defrance. Therefore, the author of Proto is de Blainville, although he mentions that the name was used before by Defrance in his collection (‘ in schedis ’). The text lists only Proto terebralis Defrance (again a collection name, made available by de Blainville (1824), which is the type species of Proto de Blainville, 1824 by monotypy. In addition, de Blainville (1824) discussed that this genus seems to be represented also by an extant species, without providing a name. De Blainville (1825: 431) repeated the description and again mentioned Proto terebralis Defrance as representative of the genus. In the accompanying atlas, de Blainville (1827: pl. 21 bis, fig 1a) illustrated this fossil shell as Proto ? turritella Defrance. He seems to have used the question mark because he had suggested that the fossil might rather be related with Potamididae or Pachychilidae in an earlier paper (de Blainville 1825). The French early Miocene Proto turritella de Blainville, 1825 was soon recognized as subjective junior synonym of Turritella cathedralis Brongniart, 1823 , from the early Miocene of France (e.g. Defrance 1828: 164; Grateloup 1846: pl. 16; Sacco 1895: 31).

Later, de Blainville (1827: pl. 21 bis, fig 1) illustrated Proto maraschinii Defrance as typical species of the genus Proto . Unfortunately, the provenience of this species is unknown, and it is unclear if it is based on a fossil or Recent shell ( Bronn 1838: 1851). Baird (1870) doubted that it was congeneric with the Miocene Proto , due to the strikingly different morphology of the aperture and base. Soon after its introduction by de Blainville (1824), Proto was frequently used and accepted for Miocene Turritellidae by European and American paleontologists (e.g. Bronn 1831: 55; Deshayes 1832: 849; Conrad 1834: 146; Bronn 1838: 1850). Baird (1870), however, recognized that the Turritellidae genus name Proto was preoccupied by Leach (1814: 353), who had introduced the name for a crustacean. [ Baird (1870) thought that Proto was also used by Oken (1815) for an annelid genus. This statement, however, is incorrect, as Oken (1815) did not use this name (see also Bousfield 1887); it was made available by Örsted (1843: 133) and thus postdates Leach (1814) and de Blainville (1824)].

Baird (1870) did not provide a replacement name for Proto de Blainville, 1824 , but he introduced the new genus Protoma to allocate solely an extant species from Western Africa, which he named Protoma knockeri . Baird (1870) discussed the similarity with the Miocene Proto cathedralis from France but clearly pointed out the differences, which in his opinion justified the introduction of a new genus name for the African species. Thus, he clearly considered the Miocene species to belong to another genus. Therefore, the type species of Protoma Baird, 1870 is Protoma knockeri Baird, 1870 (see also MolluscaBase 2018a). This contrasts with Cossmann (1912), Wenz (1939), Marwick (1957), Marche-Marchad (1960), Lozouet et al. (2001), and Harzhauser et al. (2009a), who all considered Turritella cathedralis Brongniart 1823 , as type species of Protoma .

In his revision of Viennese Miocene Turritellidae, Handmann (1882: 212) introduced the subgenus Hemitropis for Turritella cathedralis Brongniart, 1823 and Turritella gradata Menke, 1855 , without designating a type species. Both species are certainly not congeneric, and the first revisor would have to choose the type species. Handmann (1882), however, was not aware that Hemitropis was already preoccupied by Fieber (1866: 499) for an insect. Therefore, Hemitropis Handmann, 1882 is not available as replacement name for Proto de Blainville, 1824 .

The subfamily Protominae . Despite the conchological differences that separate Allmonia from Protoma , both are morphologically similar, sharing a basal sinus and a fasciole, which separate both genera from Turritellinae . Therefore, we treat Allmonia as Protominae . A third genus that is frequently listed as member of this subfamily is Protomella. Thiele (1929: 182) introduced Protomella as new subgenus of Protoma with the extant type species Protoma pulchra Sowerby III, 1905. This West African species is currently considered to be a subjective junior synonym of Turritella capensis Krauss, 1848 (MolluscaBase 2018b). The convex whorls and deeply incised suture have little in common with the extant Protoma and the fossil Allmonia and raise doubts about a close relationship. The wide but moderately deep basal sinus, which induced Sowerby (1905: 282) to discuss a relation with Protoma knockeri , differs from the deeper and narrower basal sinus of P. knockeri . The illustration of Marwick (1957), however, indicates a fasciole as typical for Protoma and Allmonia . Therefore, we tentatively would keep this species in the Protominae genus Protomella as a genus different from Allmonia and Protoma .

Figures

FIGURE 1. Paleogeography of the Paratethys during the early Miocene (Burdigalian, Eggenburgian, Sakaraulian) and the middle Miocene (Langhian, Badenian, Tarkhanian) (modified after Popov et al. 2004 and Neubauer et al. 2015).

FIGURE 2. Miocene chronostratigraphy after Gradstein et al. (2012) with regional Paratethys stages after Popov et al. (2004) and Piller et al. (2007).

FIGURE 23. A–C. Protoma knockeri Baird, 1870, syntype, Whydah (west coast of Africa). A1–A2. Syntype, NHMUK 1870.1.14.19. B1–B2. Syntype, NHMUK 1870.1.14.19. C1–C2. Syntype, NHMUK 1870.1.14.19.

FIGURE 24. Schematic drawings of apertural features. A–C. Allmonia cathedralis (Brongniart, 1823). D–F. Protoma knockeri Baird, 1870.