Conus (Monteiroconus) tsampikaensis, Psarras & Merle & Moissette & Koskeridou, 2024

Psarras, Christos, Merle, Didier, Moissette, Pierre & Koskeridou, Efterpi, 2024, The Pleistocene Conidae (Mollusca: Gastropoda) from the island of Rhodes (Greece) and their palaeoecological significance, Geodiversitas 46 (11), pp. 423-444 : 434-437

Conus (Monteiroconus) tsampikaensis n. sp.

( Figs 7-9 )

urn:lsid:zoobank.org:act:63A46EA6-1DD1-4454-8091-EA1866BD5D64

Lithoconus mercati – Chirli & Linse 2011: 166, pl. 57, figs 1a-d (non Brocchi, 1814).

ETYMOLOGY. — Named after the type locality of Tsampika section where it was found.

TYPE LOCALITY. —Tsampika,Tsampika section, Rhodes, Greece ( Fig.1 ).

TYPE HORIZON. — Ladiko-Tsampika Fm, Pleistocene, Rhodes, Greece ( Fig. 2 ).

TYPE MATERIAL. — Greece • 1 specimen; Rhodes , Tsampika ; Ladiko-Tsampika Fm , Tsampika section; Middle Pleistocene (Chibanian) to Upper Pleistocene; holotype: AMPG(IV) 4058 • 3 specimens; Rhodes , Tsampika ; Ladiko-Tsampika Fm , Tsampika section, small Tsampika section herein; Pleistocene; paratypes: MNHN.F.A88170-A88172 .

OTHER MATERIAL EXAMINED. — Greece • one specimen (not complete specimen,shellshard); Rhodes ;Tsampikasection,TSS; MiddlePleistocene (Chibanian) to Upper Pleistocene; MNHN.F.A88173 • 8 specimens; Rhodes , Tsampika ; Ladiko-Tsampika Fm , Tsampika section; Middle to Upper Pleistocene; MNHN.F.A90345 .

STRATIGRAPHIC RANGE. — Chibanian (Middle Pleistocene) to Upper (?) Pleistocene of Rhodes, Greece (this work).

DESCRIPTION

Shell

Medium-sized shell (max length of about 52.3 mm), with low angled coeloconoid spire. Early spire whorls coeloconoid, slightly elevated with three to four spiral grooves on sutural ramp.Later spire whorls flatten with coeloconoid sutural ramps. Shoulder angulated, with maximum diameter below shoulder. Subsutural flexure moderately deep to shallow, strongly curved, moderately asymmetrical. Last whorl elongated, conical.

Colour pattern

The colour pattern on the spire whorls consists of thin axial flammulae. The pattern on the last whorl consists of two levels of pigmentation. The first one consists of two broad spiral bands, separated by a wide non-fluorescent band along the anterior part of the last whorl. The second level of pigmentation consists of spirally and axially arranged fluorescent dots, dashes and small flakes interrupted by non-fluorescent bars or small blotches. The second level of pigmentation persists on the fluorescent bands and the non-fluorescent areas.

REMARKS The specimens from Tsampika ( Figs 7-8 ) are considered to be of the subgenus Conus (Monteiroconus) due to their coeloconoid and spirally grooved sutural ramp, and the relatively low spire outline. They resemble the morphology of Conus (Monteiroconus) ambiguus Reeve, 1844 in terms of the angulated shoulder, the low, angled spire, and the size of this species reaches 75 mm, while the largest specimen found in Tsampika is 70 mm. However, the spire of Conus (Monteiroconus) ambiguus Reeve, 1844 does not have spiral cords ( Monteiro et al. 2004) or has three deeply incised spire grooves ( Petuch 1975) and thus differs from the specimens from Tsampika. In addition, the pattern of the last whorl of Conus (Monteiroconus) ambiguus is usually pale and consists of a purple-cream ground colour ( Monnier et al. 2018a), although it has rarely been observed to have evenly distributed spiral rows and two slightly darker spiral bands in the middle and anterior part of the last whorl (Reeve 1844: pl. 54, fig. 244; see also Monnier et al. 2018a: fig. 2). The colour patterns of Conus (Monteiroconus) ambiguus and Conus (Monteiroconus) tsampikaensis n. sp. differ in the density of the axial flammulae on the spire (which are denser in Conus (Monteiroconus) ambiguus ) and in the presence of spiral dashes, dots, flakes and non-fluorescent bars on the spiral pattern of the Tsampika population ( Fig. 9 ).

Conus (Monteiroconus) tsampikaensis n. sp. ( Figs 7 ; 8 ) resembles other Conus (Monteiroconus) species from the Pliocene, such as Conus (Monteiroconus) antiquus Lamarck, 1810 , Conus (Monteiroconus) villalvernensis Pavia & Dulai & Festa & Gennari & Pavia & Carnevale, 2022 , and Conus (Monteiroconus) virginalis ( Brocchi, 1814) recently discussed from Italy ( Pavia et al. 2022). However, Conus (Monteiroconus) antiquus has a different colour pattern variation (see Psarras et al. 2023), while the two species discussed in Pavia et al. (2022) have a higher spire and elevated spire whorls, so we do not consider them conspecific to the Rhodes material. Juárez & Matamales-Andreu (2016) identified Conus (Monteiroconus) tabidus Reeve, 1844 , a species originally described from West Africa, from the Tyrrhenian (MIS 5e) of Mallorca. This species usually lacks a colour pattern or displays fine and irregular spiral stripes, or occasionally some subquadrate blotches on an overall white background. This pattern is very different from that observed on the Rhodes specimens. Juárez & Matamales-Andreu (2016) did not describe a residual colour pattern on the Mallorcan material.

Several elongate and low spired specimens have been identified as Conus testudinarius Hwass in Bruguière, 1792 (synonym of Conus (Chelyconus) ermineus Born, 1778 ), an extant West African species (e.g., Cuerda 1957; Anapliotis 1961, 1963a, b, 1966; Charrier 1961; Vazzana 1988; Ruggeri & Buccheri 1968; Callapez & Soares 2000; Vicens et al. 2012; Zazo et al. 2013). The occurrence of Conus (Chelyconus) ermineus Born, 1778 in the Mediterranean during the Tyrrhenian (e.g., Muhs et al. 2015) is also questionable, as no one has yet shown any of the fossils under UV light. Conus (Monteiroconus) tsampikaensis n. sp. differs strongly from Conus (Chelyconus) ermineus in the colour pattern and in the morphology of the coeloconoid spire.

Chirli & Linse (2011) found specimens resembling Conus (Monteiroconus) tsampikaensis n. sp. at Malona. The figured specimens are very similar to those found at Tsampika. One specimen from Malona, stored at the AMPG, confirms Conus (Monteiroconus) tsampikaensis n. sp being present in that locality ( Fig. 8E ). The presence of this species in Arkhangelos Fm, which is certainly older than Tsampika ( Cornée et al. 2018), indicate that the species was present in the Mediterranean during the Middle Pleistocene in at least two interglacial periods.

Figures

FIG. 7. — Conus (Monteiroconus) tsampikaensis n. sp., holotype from the Pleistocene of Tsampika section,Rhodes (Greece), AMPG (IV) 4058,seen under natural (A1, A3-A5, A7) and UV (A2, A6, A8) light. Scale bars: 1 cm.

FIG. 8. — Conus (Monteiroconus) tsampikaensis n. sp. from the Pleistocene of Rhodes (Greece) seen under natural (A1, A3, A4, A6, B1, C1, C3, C4, C6, D1, D2, D4, D6, E1, E2, E4) and UV (A2, A5, B2, C2, C5, D3, D5, E3, E5) light: A, paratype MNHN.F.A88170, Tsampika section; B, paratype MNHN.F.A88171, Tsampika section; C, paratype MNHN.F.A88172, Tsampika section; D, specimen MNHN.F.A88173; E, specimen AMPG (IV) 4059, Malona. Scale bars: 1 cm.

FIG. 9. — Detailed figures of Conus (Monteiroconus) tsampikaensis n. sp. and colour pattern comparison, whenever possible: A, holotype, AMPG (IV) 4058; B, paratype MNHN.F.A88172. Scale bars: 1 cm.

FIG. 1. — Information about the studied section of Tsampika in Rhodes, Greece: A, general tectonic setting of the southern Aegean. B, geological map of Rhodes with the site of Tsampika as a blue star (*); C, satellite position of the studied section; D, geological map of Tsampika area, displaying the section (*), the cross section of Cornée et al. (2006) (red line a-b) and the location of the section of Cornée et al. (2018) (black arrow); E, cross section of the Ladiko-Tsampika Formation in Tsampika that was studied by Cornée et al. (2006), highlighting the area of study with a blue arrow; F, synthetic stratigraphic column of the section with the Conidae specimens recovered from TSS a. Notice that TSS d and TSS gravels (above arrow) were not visible on the figured section (Fig. 2), but were identified in nearby smaller sections. Maps A and B were modified from Cornée et al. 2018; D-E from Cornée et al. 2006. TSS beds belong to the TSS1 sequence of Cornée et al. (2006, 2018).

FIG. 2. — Small section of Tsampika along the new road on the south of Tsampika beach:A, the section is located in front of a palaeo-cliff of Jurassic limestones and has a small inclination; B, the section is divided into three units, from the base to the top: 1, sandy marl with cerithids and a rich malacofauna (= TSS a bed of Fig. 1F); 2, grey marl unit rich in Cladocora (= TSS b bed of Fig. 1F); 3, silty to sandy grey marl bed (= TSS c bed of Fig. 1F); numbers indicate the position of the associated faunas;C, detailed view of the palaeo-cliff perforated by the bivalve Lithophaga; D, in situ coral branches of Cladocora caespitosa; E, assemblage with Hexaplex (Trunculariopsis) trunculus (Linnaeus, 1758) (2), Cerithium vulgatum Bruguière, 1792 (1) and Ostrea edulis Linnaeus, 1758 (3) (hammer for scale); F, Assemblage with Hexaplex (Trunculariopsis) trunculus (Linnaeus, 1758) (2), Euthria cornea (Linnaeus, 1758) (4), and Bolma rugosa (Linnaeus, 1767) (5). Scale bar: F, c. 4 cm.