Bayericerithium bayeri Petuch, 2001

Cavallari, Daniel Caracanhas, Almeida, Sérgio Mendonça & Simone, Luiz Ricardo L., 2020, Cerithiidae, Litiopidae, Modulidae and Planaxidae (Gastropoda, Cerithioidea) collected by the Marion Dufresne MD 55 expedition in southeastern Brazil, Papéis Avulsos de Zoologia 60, pp. 1-10 : 3

Bayericerithium bayeri Petuch, 2001 ( Figs. 10‑12 )

Bayericerithium bayeri Petuch, 2001: 336 , fig. 1A-C; 2013: 147, fig. 10.2C.

Type locality: Brazil, Pernambuco State, off Gaibu, on muddy sand bottom, 2 m depth near coralline algal reef.

Distribution: Brazil, state of Pernambuco, 2 m depth ( Petuch, 2001).

New occurrences: Brazil: Ceará, Rio Grande do Norte, Bahia and Espírito Santo states, at 18-120 m depths.

Material examined: Brazil; off Espírito Santo: continental slope of Abrolhos , 18°50′S, 37°57′W, 60 m, 4 shells, MZSP 105301 , 2 shells ( MD55 , sta. DC83 , 28/v/1987) ; 18°59′S, 37°48′W, 607-620 m, MNHN, 1 shell, ( MD55 , sta. DC73 , 27/v/1987) ; Jaseur Seamount , 20°27′S, 35°54′W, 54 m, MNHN, 2 shells (sta. DC34; 15/v/1987) .

Additional (non‑MD55) material: Brazil; Ceará: off Fortaleza, 18 m depth, MZSP 33517 , 1 shell (H. R. Matthews col., VI /1967; former H. R. Matthews collection, № 491). Rio Grande do Norte: off Touros, Praia do Cajueiro , 18-21 m, MZSP 100667 , 2 shells (col. by diving, 2011; under rocks) ; off Rio do Fogo, 20-25 m, MZSP 67938 , 1 shell (A. Bodart col., III/1999; in coral sand), MZSP 70225 , 3 shells (A. Bodart col., III/1999; in coral sand), 10-15 m, MZSP 74554 , 38 shells (M. Coltro col., I/2007). Bahia: Minerva Seamount , 17°01′S, 37°37′W, 50 m, MZSP 107939 , 5 spm (dredged, J. Coltro col., 12/ VIII /2012), 17°06′S, 37°38′W, 120 m, MZSP 110859 , 15 spm (dredged, local fishermen col., VIII /2012), MZSP 110910 , 66 shells (dredged, local fishermen col., VIII /2012), MZSP 110959 , 20 spm (dredged, local fishermen col., VIII /2012) ; off Alcobaça, 5-10 m, MZSP 33188 , 8 spm (A. Bodart col., VII /2001), MZSP 34065 , 21 spm (A. Bodart col., VII /2001), MZSP 65240 , 10- 12 m, 2 shells (A. Bodart col., VII /2001), MZSP 65241 , 2 shells (A. Bodart col., I/2005;in coral sand), MZSP 69418 , 15 spm (A.Bodart col., I/2005; in coral sand), 20-25 m, MZSP 69417 , 1 spm (A. Bodart col., I/2005; in coral sand), MZSP 71941 , 1 shell (A. Bodart col., IX/2001; in coral sand), MZSP 72318 , 24 shells (A. Bodart col., VI /2001; in coral sand), Escalada Reef , 5-10 m, MZSP 34545 , 2 spm (A. Bodart col., I/2002) ; unknown locality off southern Bahia, MZSP 35897 , 4 shells (local fishermen col., 2002). Espírito Santo: off Guarapari, MZSP 91069 , 6 spm (J. Coltro col., 2009) .

Measurements (± standard deviation, in mm; n = 9): W = 2.32 ± 0.91; H = 4.01 ± 1.49.

Remarks: Although all the MD 55 specimens are juvenile empty shells ( Figs. 11-12 ), they compare exceedingly well with the earliest whorls of well-preserved adult specimens from relatively close locations. Adult B. bayeri have thick, stubby shells, but the initial spire whorls have a straight conical outline in some specimens ( Petuch, 2001: fig. 1A-C). Ground color is cream-white, with widely spaced orange bands arranged in a zebra-like pattern, as reported by Petuch (2001) in the original description. In the present specimens, these colors are sometimes mixed with a diffuse violet-pinkish shade, especially in the initial 2-3 teleoconch whorls. The MD 55 specimens also have poorly developed sculpture except for very faint subsutural knobs and numerous densely packed spiral threads, which compares well with the original description. The distribution of B. bayeri was originally restricted to Pernambuco, but it is herein greatly expanded ca. 510 km northward to Rio Grande do Norte and Ceará states, and ca. 1,350 km southward to the states of Bahia and Espírito Santo. Petuch (2013) considered B. bayeri endemic to the Cearaian Biogeographic Subprovince (sensu Petuch, 2013), but the records reported herein are evidence of a wider range. In this sense, the species also occurs in the author’s neighbor Bahian Province (from Alagoas to Rio de Janeiro states). The species’ bathymetric range is also expanded as live specimens were collected at depths of up to 120 m (the only deeper record consists of empty shells, which were probably carried). Bayericerithium has been recently listed as a synonym of Cerithium in online taxonomic databases (e.g., Rosenberg, 2009, 2014), which also list Cerithium bayeri ( Petuch, 2001) as the valid combination. However, there is a Cerithium bayeri Beets, 1941 , a fossil species from the Miocene of Indonesia ( Beets, 1981). This would make C. bayeri ( Petuch, 2001) a junior secondary homonym according to the ICZN (Art. 57.3). In the light of these facts, and since no formal revision including Bayericerithium has been published so far, we have chosen to keep the original combination.

Figures

Figures 1-20. Cerithiidae and Litiopidae collected by the MD55 expedition off SE Brazil;(1-6) Ittibittiumoryza; (1-3) MZSP 122161,sta.DC22 (L 4.5 mm),(1) apertural, (2) right lateral and (3) apical views;(4-6) MNHN, sta. DC35 (L 3.8 mm), (4) apical,(5) apertural and (6) right lateral views; (7-9) Cerithium atratum, MNHN, sta.DC34 (L 3.2 mm), (7) apertural, (8) right lateral and (9) apical views; (10-12) Bayercerithium bayeri juvenile specimen, MNHN, sta. DC34 (L 2.5 mm), (10) apical, (11) apertural, and (12) right lateral views; (13-15) Alaba incerta MNHN, sta. CB96 (L 3.8 mm), (13) apertural view, (14) right lateral, (15) protoconch detail, (16) apical view (scale = 0.2 mm). (17-20) Litiopa melanostoma MNHN,sta.DC72 (L 4.5 mm), (17) protoconch detail (scale = 0.2 mm), (18) apical,(19) apertural, (20) right lateral views.