Africonus trochilus ( Mayer, 1864 )

Sacchetti, Claudia, Landau, Bernard & Ávila, Sérgio P., 2023, The Lower Pliocene marine gastropods of Santa Maria Island, Azores: Taxonomy and palaeobiogeographic implications, Zootaxa 5295 (1), pp. 1-150 : 81-82

Africonus trochilus ( Mayer, 1864)

Plate 5 M

Conus trochulus Reeve —Bronn in Reiss 1862: 24, pl. 1, fig. 2 [non Trovaoconus trochulus (Reeve, 1844) ].

* Conus trochilus Mayer 1864: 80 , pl. 7, fig. 60.

Type material. Single specimen length 16.0 mm, width 9.0 mm (incomplete spire fragment), Pinheiros (Baía da Cré), Santa Maria Island, Azores; whereabouts unknown ( Beu 2017:165) .

Original description. “ Eine kleine nur 6''' lange Art mit sehr flach-geŵlbtem Gewinde, vielleicht dem flächsten unter allen von dieser geringen Gr̂sse, und ohne Abstufung seiner 7-8 Umgänge; die Kante des letzten derselben abgerundet und einfach. Die ganze Oberfläche glatt und nur nächst dem vordern Ende mit Spuren von einigen Spiral-Streifen. Viel kleiner und die äussre Kante des Gewindes ausgeprägter, als an der fŗher als C. pyrula ? aufgef̧hrten Art. Vielleicht dem Conus trochulus REEVE von den Capverdischen Inseln entsprechend? [ A small species, only 6''' [lines] long species with very flattened spire, perhaps the flattest of all of this small size, and without the 7-8 spire whorls being scalate; the edge of the last is rounded and simple. The whole surface is smooth and only next to the anterior end are traces of some spiral cords. Much smaller and the outer edge of the suture more pronounced than on the previously mentioned as C. pyrula? Perhaps being the same as Conus trochulus Reeve from the Cape Verde Islands?] (Bronn in Reiss, 1862: 24).

Discussion. Tucker & Tenorio (2009: 83) placed this species in the genus Africonus Petuch, 1975 , which are characterise by shells with cords on the spire whorls, the top of which may be concave, a shallow to moderately deep anal notch, and a paucispiral protoconch. No further specimens are available to further characterised this species. Today the genus is restricted to the Cabo Verde Islands.

Distribution. Lower Pliocene: Atlantic, Santa Maria Island, Azores (Mayer, in Bronn in Reiss 1862; Mayer 1864).

Genus Lautoconus Monterosato, 1923

Type species. Conus mediterraneus Hwass in Bruguière, 1792 ( Monterosato 1923: 11), by original designation. Present-day, Mediterranean.

Figures

PLATE 5. A1-A2. Tritia atlantica (Mayer, 1862), DBUA-F 1295-2, height 13.0 mm, width 6.5 mm, Malbusca (east cave). B1-B2 C1-C2. Tritia serraticosta (Ĥrnes, 1852), DBUA-F 1292-A, height 6.2 mm, width 4.1 mm (B); height 8.1 mm, width 4.2 mm (C), Macela viewpoint. D. Tritia vetulum (Mayer, 1862), height 12.0 mm, width 6.0 mm, Pinheiros (figure taken from Bronn in Reiss, 1862, pl. 1, fig. 5). E1-E2. Aplus sp., height 7.5 mm, width 4.0 mm, Ponta do Castelo, LNEG collection (unnumbered). F1- F2. Orania cf. bellardiana (Foresti, 1884), DBUA-F 828-2, height 17.0 mm, width 12.0 mm, Ponta dos Frades. G1-G2. Favartia suboblonga (d’Orbigny, 1852), DBUA-F 946-3, height 19.0 mm, width 10.0 mm, Ponta dos Cedros. H1-H2. Bellardithala obsoleta (Brocchi, 1814), DBUA-F 542-4, height 5.9 mm, width 2.0 mm, Ponta dos Frades. I1-I2 J. Cancilla volvaria (Bronn, 1862), DBUA-F 937-2, height 10.9 mm, width 4.8 mm (I), Ponta do Castelo; height 15.5 mm, width 5.5 mm (J), Pinheiros (figure taken from Bronn in Reiss, 1862, pl. 1, fig. 4). K. Mitra (s.l.) peregrinula Mayer, 1864 species inquirenda, height 5.5 mm, width 2.5 mm, Feteirinhas (= Ponta das Salinas) (figure taken from Mayer, 1864, pl. 7, fig. 61). L1-L2. Mitra (s.l.) sp., DBUA-F 1295-3, height 12.9 mm, width 7.0 mm, Malbusca (east cave). M. Africonus trochilus (Mayer, 1864), length 16.0 mm, width 9.0 mm (incomplete spire fragment), Pinheiros, (figure taken from Mayer, 1864, pl. 7, fig. 60). N1-N2. Lautoconus cf. anomalomamillus (Sacco, 1893), DBUA-F 924-1, height 22.0 mm, width 11.0 mm, Malbusca. O. Plagioconus sp., height 35.5 mm, width 16.0 mm, unknown locality, LNEG collection (unnumbered). P1-P2 Q. Stephanoconus candidatus (Mayer, 1862), DBUA-F 913, diameter 19.0 mm (apical fragment of juvenile), Ponta dos Frades (P); diameter 40.0 mm, height 22.0 mm (incomplete spire fragment), Pinheiros (figure taken from Bronn in Reiss, pl. 1, fig. 1).