Monophorus caracca Fernandes & Pimenta 2020, comb. nov.
Creators: name: Fernandes, Maurício Romulo
name: Pimenta, Alexandre Dias
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Triphoridae
Monophorus
Monophorus caracca

description: Monophorus caracca (Dall, 1927) comb. nov.
Figs 10, 23N, 57
Triphora (Biforina) caracca Dall, 1927: 92.
“ Triphora ” caracca – Rolán & Fernández-Garcés 2008: 140, fig. 24a–e.
Material examined
Lectotype
UNITED STATES OF AMERICA – off Georgia • 30º43′59″ N, 79º25′59″ W; depth 805 m; 1 Apr. 1885; R/V Albatross leg.; USNM 108343. Two paralectotypes are also found under the same lot number.
Other material
BRAZIL – off Espírito Santo • 4 specs; MD55 st. 42-DC75; MNHN *.
Description
Shell sinistral, elongated, conical, rectilinear profile, the better-preserved shell is 5.7 mm long, 1.5 mm wide, although complete adult shells may be much larger. Protoconch multispiral but partially broken; penultimate whorl with cruciform granules spirally disposed; last whorl with two spiral cords, situated at ~31% and ~62% of whorl height, crossed by weak axial ribs, despite a smooth spiral zone (i.e., without axial sculpture) just above the adapical spiral cord; prosocline (below suture) to opisthocline (below adapical cord) axial ribs. Teleoconch with up to 14 whorls; two spiral cords (adapical and abapical) at beginning, abapical one continuous to that of protoconch; median spiral cord emerges very weakly in sixth/seventh whorl, much close to adapical cord, gradually strengthening but not reaching same size of other cords even after eight whorls; in late whorls, the spiral cords are 2.0–3.5 × as wide as distance between them; 16 opisthocline axial ribs; rounded to elliptical nodules of medium size, pointed profile, keeled-shaped, especially in abapical cord; median spiral cord initially wavy, acquiring nodules after many whorls; distinct but somewhat shallow suture, with small sutural cord that gradually strengthens and becomes thick in late whorls; additional spiral cord emerges in very late whorls, immediately above adapical spiral cord; thick, smooth subperipheral cord, one thin and smooth basal cord much close to subperipheral cord; base and canals not formed or considerably damaged. Brown protoconch, white teleoconch.
Remarks
The present species shows a late median spiral cord of the teleoconch (Fig. 10J), a protoconch with cruciform granules and a smooth spiral zone (Fig. 10G), features which are also observed in Monophorus (Marshall 1983). Monophorus caracca (Dall, 1927) comb. nov. was described from the deep sea off Georgia (USA). After comparisons with the type material (Fig. 10A), the single minor difference being the median spiral cord emerging in the sixth/seventh whorl of the teleoconch in a Brazilian shell, but it emerging discreetly in the eighth whorl of the lectotype, being properly detected only in the tenth whorl (Rolán & Fernández-Garcés 2008). In addition, the bathymetric record of the type locality is deeper than seen in Brazil (805 m and 295 m, respectively).
Agreeing with the initial assignment of this species to the subgenus Biforina (currently a synonym of Monophorus) by Dall (1927), this species is now regarded as belonging to Monophorus. Although Dall (1927) did not explain the etymology of the specific name, ‘ caracca ’ is a word in Italian which refers to large sailboats/ships used during the Great Navigations; because it is a noun, the ending remains unaltered after the new generic allocation (ICZN 1999: article 31.2).
Geographical records
USA: off Georgia (type locality). Brazil: off Espírito Santo (this study).
Bathymetric distribution
Depth: 295 m (this study) to 805 m (type locality).
description: Published as part of Fernandes, Maurício Romulo & Pimenta, Alexandre Dias, 2020, Unraveling one of the ' Big Five': update of the taxonomy of Triphoridae (Gastropoda, Triphoroidea) from Brazil, pp. 1-170 in European Journal of Taxonomy 665 (665) on pages 25-27, DOI: 10.5852/ejt.2020.665, http://zenodo.org/record/3899047