Clathrodrillia gibbosa (Born, 1778)

Fallon, Phillip J., 2016, Taxonomic review of tropical western Atlantic shallow water Drilliidae (Mollusca: Gastropoda: Conoidea) including descriptions of 100 new species, Zootaxa 4090 (1), pp. 1-363 : 96-99

Clathrodrillia gibbosa (Born, 1778)

(Fig. 42)

Murex gibbosus Born, 1778: 325 ; Born (1780: 321, pl. 11, figs. 12, 13); Chemnitz (1795: 112–113, pl. 190, figs. 1829–1830); Grant & Gale (1931: 579, pl. 26, figs. 3a, b = Born’s figs.); E. H. Vokes (1971: 53).

Pleurotoma gibbosa (Born, 1778) : Sowerby I (1825: 58, cat. no. 1500).

Pleurotoma gibbosa Kiener 1840b: 35 , pl. 12 [sic, 16], fig. 2. Kiener redescribed Born’s species and took authorship of the new combination.

Pleurotoma gibbosa “Chemnitz”: Reeve (1843b: pl. 5, sp. 30), an erroneous attribution by Reeve.

Drillia gibbosa “Chem.”: H. & A. Adams (1853: 90 [list]), an erroneous attribution by these authors.

Pleurotoma (Drillia) gibbosa (Born, 1778) : Chenu (1859: 146, fig. 650 [as an example of the genus]); Paetel (1888: 63 [list]).

Drillia (Brachystoma) gibbosa (Born, 1778) : Tryon (1884: 179, pl. 9, fig. 54 [= Reeve’s fig.]).

Clathrodrillia gibbosa “Reeve”: Dall (1918a: 317, 323) is an erroneous attribution by Dall.

Turris gibbosa (Born, 1778) : M. Smith (1940: 80, sp. 1110).

Clavus (Clathrodrillia) gibbosa (Born, 1778) : Korobkov (1955: pl. 104, fig. 6).

Clathrodrillia mareana Weisbord, 1962: 437 , pl. 41, figs. 16–17 [fossil], is a synonym according to Woodring (1970: 383).

Clathrodrillia gibbosa (Born, 1778) : Powell (1966: pl. 11, fig. 2); Kaicher (1984c: card 3944); K. Sunderland (1991: 14, text photo); Díaz (1994: 40 [incorrectly gives authorship date as 1780]); Diaz & Puyana (1994: 226, pl. 68, fig. 896); Rolán & Espinosa (1995); C.-K. Chang (2001a: 18, figs. 3–8; 215, figs. 19–22); Macsotay & Campos (2001: 108, pl. 9, figs. 1, 8); Williams (2005: species 1542); Massemin et al. (2009: 205); Daccarett & Bossio (2011: 129, fig. 785).

Drillia (Clathrodrillia) gibbosa (Born, 1778) : Abbott (1974: 270, fig. 2999).

Crassispira gibbosa (Born, 1778) : Sutty (1986: 125, fig. 139).

Drillia gibbosa (Born, 1778) : Vermeij (1978: 274); Harasewych & Moretzsohn (2010: 573, text figs.).

Not this species, fossil, or unconfirmed extralimital reports.

Pleurotoma gibbosa (Born, 1778) : Simpson (1887c: 54 [Anna Maria Key, W Florida: “one slightly worn shell”]).

Crassispira (Clathrodrillia) gibbosa (Born, 1778) : Wenz (1943: 1408, fig. 3978 [fossil occurrence]); Glibert (1960 [fossil occurrence]).

Clathrodrillia gibbosa (Born, 1778) : Fargo (1953: 368; pl. 16, figs. 1, 1a [fossil occurrence]); Weisbord (1962: 435, pl. 41, figs. 13–15 [fossil occurrence]); Olsson (1964: 96 [fossil occurrence]); Woodring (1970: 383 [fossil occurrence]).

Type material. Unknown. Born’s drawing is taken as representative of the type. The drawing is somewhat artistic, but since there is little confusion about the identity of this species the designation of a neotype at this time is unnecessary.

Type locality. Unknown. Stated as Cumaná, Venezuela, by Weisbord (1962: 437) erroneously citing Fargo (1953: 368; pl. 16, figs. 1, 1a) who did not give the type locality. The type locality was unknown to Born (“ patria ignota ”). The type locality of Clathrodrillia mareana Weisbord, 1962 is lower Mare Formation on hillside above west bank of Quebrada Mare Abajo, northern Venezuela (Weisbord, 1962: 438) [=Pliocene (Woodring, 1970: 383)].

Material examined. A total of 100 specimens were examined. Venezuela: 1 spec., 48.9 x 17.3 mm, in 15 m, Coche I., Nueva Esparta, G. Mackintosh! Sep 1999 (author’s coll.), 70 spec., 48.1 x 18.3, 48.5 x 18.0, 47.3 x 16.7, 49.4 x 17.6, 48.4 x 18.0, 46.9 x 17.6, 48.6 x 17.2, 47.3 x 18.3, 47.1 x 17.0, 49.2 x 19.0, 47.8 x 17.6, 53.8 x 19.0, 49.0 x 17.3, 48.0 x 17.6, 50.9 x 18.2, 42.0 x 15.4, 42.5 x 16.0, 41.8 x 15.4, 44.1 x 16.3, 47.1 x 16.7, 42.6 x 16.2, 46.8 x 17.5, 41.7 x 16.1, 44.6 x 16.2, 42.7 x 15.6, 41.2 x 15.4, 47.1 x 16.6, 43.1 x 15.8, 44.6 x 16.1, 46.6 x 17.2, 42.8 x 15.5, 41.0 x 15.6, 47.3 x 18.0, 45.2 x 17.2, 44.4 x 15.7, 40.6 x 15.2, 47.8 x 17.8, 48.4 x 16.8, 49.4 x 17.9, 52.1 x 19.5, 46.6 x 16.7, 46.5 x 16.9, 47.5 x 17.3, 52.5 x 19.2, 47.5 x 16.7, 49.5 x 18.6, 51.3 x 18.2, 49.0 x 17.1, 48.9 x 18.1, 46.2 x 16.6, 49.1 x 17.7, 47.9 x 16.5, 50.4 x 18.4, 53.6 x 19.7, 44.7 x 17.8, 44.5 x 16.7, 44.1 x 16.0, 44.4 x 17.3, 44.0 x 16.5, 44.5 x 17.4, 44.9 x 17.9, 46.1 x 15.9, 45.9 x 16.5, 46.3 x 16.8, 43.7 x 16.1, 44.1 x 16.6, 44.3 x 16.4, 46.9 x 17.2, 44.1 x 16.7 & 44.4 x 16.5 mm, in 8–14 m, N side of Coche I., Nueva Esparta, G. Mackintosh! 21–25 Sep 1999 (author’s coll.); 18 spec., 25.9 x 9.9, 24.7 x 10.1, 32.7 x 12.7, 28.5 x 11.3, 23.2 x 9.2, 24.8 x 9.8, 26.0 x 9.8, 26.9 x 10.3, 26.2 x 10.3, 27.9 x 10.8, 28.6 x 10.7, 28.4 x 11.0, 27.7 x 10.6, 32.5 x 12.4, 32.1 x 12.3, 32.6 x 11.6, 45.3 x 16.3, 50.0 x 18.5 mm, in 5 & 12 m, W end of Coche I., Nueva Esparta, G. Mackintosh! 31 Oct–2 Nov 1999 (author’s coll.); 1 spec. 44.2 x 16.7mm, in 12 m, N side of Coche I., Nueva Esparta, G. Mackintosh! 25 Sep 1999 (UF 470284); 1 spec., 49.6 x 18.7 mm, in 14 m, N side of Coche I., Nueva Esparta, G. Mackintosh! 4– 5 Jul, 1993 (UF 470282); 1 spec., 50.5 x 19.1 mm, in 6 m, Pampatar, Margarita I., Nueva Esparta, G. Mackintosh! (UF 470281); 1 spec., 36.9 x 14.2 mm, in 37 m, off Margarita I., Nueva Esparta, 1996 (UF 470283); 5 spec., 29.3 x 10.6, 25.0 x 9.3, 29.7 x 10.8, 30.1 x 11.4 & 32.9 x 12.5 mm, in 7 m, Bahia Guamache, Margarita I., Nueva Esparta, G. Mackintosh! 29 Jul 2001 (author’s coll.); 2 spec., 29.1 x 10.4 & 30.6 x 10.6 mm, in 6m, Pampatar, Margarita I., Nueva Esparta, G. Mackintosh! 24 Jun 1993 (author’s coll.).

Range and habitat. Colombia (Magdalena Dept.; Guajira Dept.); Venezuela (Zulia; Falcon; Sucre; Nueva Esparta: Margarita I.; Coche I.; Cubagua I.); Guyana; Suriname. It has been taken live by divers in relatively shallow water especially around Margarita I. (and the nearby uninhabited islets of Coche and Cubagua). Divercollected material has been reported from 6–20 m depths, and from towed gear in as deep as 60 m.

This taxon has been applied to fossil specimens in some of the works listed in the synonymy above. Fossils have been reported from Venezuela (Lower Mare Formation, Weisbord, 1962) and from as far north as Sarasota Co., W Florida (Caloosahatchee Formation [YPM IP 559859]), which indicates a much wider distribution of this species during Pliocene-Pleistocene Epochs (5.3 million–11,700 years BP) than at present. Fossil specimens were not examined in this work to determine their degree of similarity to Recent specimens.

Description. Shell large (to 53.8 mm in total length), fusiform, truncated anteriorly, with a tall, turreted spire, whorls straight to slightly convex and total about 14½; last whorl approximately 52% of the total length, constricted anteriorly by a furrow created by the stromboid notch. Sutures impressed, with a collar adjoining below. Sculpture of numerous ribs cut by spiral grooves. Aperture oval with a short but distinct anterior canal. Protoconch of approximately 1¾–2 smooth round whorls. Beginning of teleoconch usually obscure but marked by the first axial. Axial Sculpture of numerous thin axial ribs that extend from suture-to-suture, very slightly opisthocline on the spire whorls, more so on the last; narrower than their interspaces, 21–23 on the penultimate, 13–17 on the last whorl to the varix, the last 4–5 ribs larger, more widely spaced and acutely hooked at the shoulder. Ribs reduced to narrow crescents in sulcus of early whorls, finer crescents in later whorls that override collar to suture but obscured by coarse growth striae. Varix large, broad, hump-like, approximately ¼- to ⅓-whorl from the edge of the outer lip. Spiral Sculpture of incised grooves that cut the axial ribs creating a somewhat cancellate appearance, 6–8 on penultimate and 9–13 more on shell base to ridge demarcating anterior fasciole. Sulcus with convex collar at suture, then a furrow at shoulder, which is the trace left but the apex of the anal sinus. Curved traces of ribs and spiral grooves appear in the sulcus of early whorls, but are entirely obscured by the heavy collar and growth striae on later whorls. Outer lip flattened from varix to edge of lip, jutting out beyond the margin of the previous whorl, and bearing several low axial folds, and a large reinforcing rib near edge; edge of lip forms a low arc along its length, heavily scalloped by tooth extensions of the spiral grooves. Stromboid notch deep, creating a spiral furrow that marks the shell base constriction. Anal sinus deeply notched, sides asymmetrically U-shaped, the outer lip side projects beyond the parietal wall side; sinus directed away from the main axis of the shell by heavy parietal lobe, flared inner edge of sinus, and outward flex of outer lip gives sinus a spout-like appearance. Inner lip moderately wide, heavily enameled, emarginated, erect anteriorly along columella, recumbent and widest on parietal wall, developed into a heavy parietal lobe posteriorly. Anterior canal short but distinctly formed, open, with a deep apical notch, U-shaped, with an upturned end. Fasciole short, emerging from underneath current outer lip about halfway up the columella, bounded from shell base ridge along its margin; surface with dense incremental crescentshaped growth striae only. Color dirty white with a reddish-brown band, confined mostly to rib crests, white to grayish between ribs, extending from shoulder to mid-whorl (to near suture on spire whorls) and with an additional band on shell base; varix with a pale to dark brown blotch; aperture reddish brown.

Remarks. Taxonomy. Born’s Latin description of the species was very brief. Clathrodrillia gibbosa was redescribed and placed in Pleurotoma by Kiener in his 11 volume work (Kiener, 1840). Dall (1918) subsequently selected this species as the type of Clathrodrillia , but did not describe it further. A more complete description of C. gibbosa was published by Fargo (1953: 368; pl. 16, figs. 1, 1a). Variability. Mature specimens can be quite variable in size, probably due to environmental factors. The smallest completely developed specimen, with varix and projecting scalloped lip, encountered in this work is 23.2 mm in total length (see Pl. 42, Fig. 7). The average total length of 100 specimens is 42.32 mm (23.2–53.8 mm), their average W/L is 0.371. The greatest length reported in the literature is 75 mm (Kaicher, 1984, card 3944); however, this may be a typographical error. The largest reported elsewhere is 60 mm (M. Smith, 1940: 80), which is still quite large compared to the 53.8 mm maximum specimen size examined for this work. Identification. This is a distinctive species; with the possible exception of Simpson’s 1887c report, miss-identifications have not been found in the published literature. The closest congener, C. petuchi (Tippett, 1995) , differs in being stockier, having wider and fewer ribs, and a different coloration, pale yellow to orange bands rather than brown. The varix also has a much lighter colored patch than in C. gibbosa .