Douglassia bealiana Schwengel & McGinty, 1942

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: 133-136

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http://doi.org/10.11646/zootaxa.4090.1.1

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scientific name

Douglassia bealiana Schwengel & McGinty, 1942
status

 

Douglassia bealiana Schwengel & McGinty, 1942 

( Plate 59View PLATE 59)

Douglassia bealiana Schwengel & McGinty, 1942: 15  , pl. 4, fig. 2. Powell (1966: 90); Williams (2005; 2009: species 1554); Rosenberg et al. (2009: 665).

Cerodrillia bealiana (Schwengel & McGinty, 1942)  : Porter (1974: 246); Kaicher (1984: card 3985); García & Lee (2002: 12); García (2002 a: 10).

Cerodrillia bealiana Schwengel & McGinty, 1942  [sic: missing parens]: Abbott (1974: 272); Turgeon et al. (1988: 96); Turgeon et al. (1998).

Cerodrillia clappi  auct. non Bartsch & Rehder, 1939: Odé (1991: 25) may be this species.

Cerodrillia cf. clappi Bartsch & Rehder, 1939  : Tunnell et al. (2010: 242, text photo) is probably this species.

Not this species or unconfirmed extralimital reports.

Douglassia bealiana (Schwengel & McGinty, 1942)  [sic: parens in error]: Rios (1975: 132, pl. 40, fig. 592 [off Amapá, Brazil; fig. 592 not recognizable as D. bealiana  ]).

Douglassia bealiana Schwengel & McGinty, 1942  : Rios (1985: 137, pl. 47, fig. 629 [off Amapá, Brazil; fig. 629 reproduced from Schwengel & McGinty (1942)]); de Barros et al. (2005 [Piedade, Brazil; not figured]).

Drillia bealiana Schwengel & McGinty, 1942  [sic: missing parens]: Rios (1994: 159, pl. 53, fig. 706 [off Amapá, Brazil; fig. 706 reproduced from Schwengel & McGinty (1942)]).

Cerodrillia bealiana Schwengel & McGinty, 1942  [sic: missing parens]: Rios (2009: 310 [N Brazil; fig. 782 reproduced from Williams (2005: species 1554, left photograph)]).

Brazilian occurrence could not be confirmed from figures in available references.

Type material. Schwengel & McGinty (1942: 16) note that the “ type ” is cataloged in ANSP 178702. This is an implicit holotype declaration because no other specimens are mentioned in the article (ICZN 2000 Article 73.1.1). Eight other specimens (in 4 lots), which are labeled “ types ” or “ paratypes ”, found in museum drawers have essentially the same data label information as the holotype, are likely to have been examined by one or both of the describers, and thus may possibly be considered part of the original type series (ICZN 2000 Article 72.4.1.1), in this case paratypes. They are: 1 spec. 7.0 x 2.7 mm, T.L. & P.L. McGinty! Oct 1941 (ANSP 178702); 3 spec., 6.9 x 3.2, 6.7 x 3.1 & 7.1 x 3.1 mm, in 26 m, 10 km E and 6 km offshore of Destin, Florida, T.L. & P.L. McGinty! Oct 1941 (ANSP 178719); 2 spec., 5.2 x 2.6 & 7.1 x 3.1 mm, in 26 m, 10 km E and 6 km offshore of Destin, Florida, T.L. & P.L. McGinty! Oct 1941 (MCZ 207075); 2 spec., 7.1 x 2.9 & 7.3 x 3.4 mm, in 26 m, 10 km E and 6 km offshore of Destin, Florida, T.L. & P.L. McGinty! Oct 1941 (MCZ 207350); 1 spec., 6.9 x 3.1 mm, in 26 m, 10 km E and 6 km offshore of Destin, Florida, T.L. & P.L. McGinty! Oct 1941 (MCZ 226785).

Type locality. 6 mi [10 km] E and 4 mi [6 km] offshore of Destin, Florida, in 14 fms [26 m] depth.

Other material examined. An additional 95 specimens were examined: Louisiana. 9 spec., 2.7 x 1.6, 3.9 x 2.1, 4.0 x 2.0, 4.4 x 2.1, 4.5 x 2.2, 5.0 x 2.4, 5.6 x 2.5, 6.3 x 2.7, 6.3 x 2.8 mm, in 57–65 m, offshore Louisiana, 26 ° 6.866 'N, 91 ° 2.418 'W, E. García! aboard R/V Pelican, 30 Jun 2001 (H.G. Lee coll.); 2 spec., 6.4 x 3.0 & 5.1 x 2.5 mm, in 71–74 m, offshore, 28 °03.439'N, 92 ° 26.978 'W, E. García! aboard R/V Pelican, 30 Jun 2001 (EFG 23380); 2 spec., 5.0 x 2.3 & 4.6 x 2.3 mm, in 76 m, offshore, 28 ° 6.17 'N, 91 ° 2.13 'W, E. García! aboard R/V Pelican, 3 Jul 2003 (EFG 24626); 2 spec., 7.7 x 3.3 & 6.7 x 3.0 mm, in 88 m, offshore, 28 ° 4.57 'N, 90 ° 59.99 'W, E. García! aboard R/V Pelican, 4 Jul 2003 (EFG 24654); 1 spec., 5.4 x 2.6 mm, in 60–70 m, Sackett Bank, 28 ° 38.16 'N, 089° 33.19 'W, E. García! aboard R/V Pelican, 7 Jun 2004 (EFG 25760); 1 spec., 7.1 x 3.2 mm, in 68–104 m, Sackett Bank, 28 ° 37.86 'N, 89 ° 33.25 'W, E. García! aboard R/V Pelican, 24 Nov 1996 (EFG 28065); 1 spec., 3.9 x 2.4 mm, in 68 m, Ewing Bank, 28 ° 5.85 'N, 91 ° 1.28 'W, E. García! aboard R/V Pelican, 3 Jul 2003 (EFG 24619). W Florida. 2 spec., 6.4 x 2.9 & 6.7 x 3.0 mm, in 24–35 m, 24–56 km off Fort Walton Beach, L.A. Burry! (MCZ 145856); 20 spec., the best 2: 6.4 x 3.2, 6.1 x 2.8 mm, in 37–55 m, off Panama City, Bay Co. (DMNH 107146); 1 spec., 7.0 x 3.4 mm, in 55 m, SW of Panama City, Bay Co., J. Moore! (EFG 11567 A); 1 spec., 6.3 x 3.1 mm, in 55 m, SW of Panama City, Bay Co., J. Moore! (EFG 11823); 2 spec., 6.9 x 3.1 & 6.7 x 3.0 mm, in 55 m, SW of Panama City, Bay Co., J. Moore! (EFG 11798); 5 spec., 8.1 x 3.3, 6.6 x 2.8, 7.2 x 2.9, 7.1 x 3.0 & 4.1 x 2.0 mm, in 183 to 229 m, W of Cape San Blas, Gulf Co., R. & D. Black! Jul 1973 (USNM 900103); 5 spec., 9.9 x 4.4, 8.2 x 4.1, 7.9 x 3.6, 6.0 x 2.8 & 5.4 x 2.7 mm, in 55 m, SW of Panama City, Bay Co., J. Moore! Aug 1963 (USNM 900105); 2 spec., 6.6 x 2.9, 5.1 x 2.4 mm, WSW of John’s Pass, Pinellas Co. (DMNH 107718); 1 spec., 8.6 x 3.7 mm, in 30 m, off Egmont Key, Hillsborough Co., J. Moore! (ANSP 336132); 1 spec., 7.3 x 3.1 mm, in 54 m, ca. 100 km W of Boca Grande (26 ° 46.476 'N, 83 ° 18.552 'W) E. García! aboard R/V Pelican, 4 Jun 2004 (EFG 25420); 11 spec., 2 best 2: 6.6 x 3.0 & 7.5 x 3.6 mm, W of Florida in Gulf of Mexico, J. Moore! (USNM 900104). Florida Keys. 1 spec., 7.5 x 3.3 mm, in 61 m, off Marathon Key, coll. 1978 (USNM 900142). E Florida. 17 spec., 7.5 x 3.3, 8.3 x 3.7, 8.3 x 3.8, 7.9 x 3.5, 8.1 x 3.6, 8.2 x 3.7, 8.0 x 3.5, 7.6 x 3.5, 7.2 x 3.2, 7.5 x 3.3, 7.4 x 3.5, 6.8 x 3.1, 9.4 x 5.0, 8.5 x 3.9, 8.3 x 3.6, 7.7 x 3.2 & 6.4 x 2.8 mm, scallop dump at Camp Alamacani, Xalvis I., Duval Co. (H.G. Lee coll.); 1 spec., 5.0 x 2.8 mm, ex batfish in about 30 m, 56 km E of Mayport, Duval Co., H.G. Lee! 17 Aug 1985 (H.G. Lee coll.); 1 spec., 7.7 x 3.7 mm, in 30 m, 32 km SE of Mayport, Duval Co. (DMNH 181802); 2 spec., 8.9 x 3.9 & 7.9 x 3.5 mm, in 30 m, 20 mi SE of Mayport, Duval Co. (USNM 900106); 2 spec., 7.5 x 3.7 & 7.3 x 3.5 mm, in 27–34 m, off Jacksonville, Scallop boats! (EFG 9944); 9 spec., the best 3: 7.3 x 3.3, 5.5 x 2.7, 7.8 x 3.5 mm, in 38 m, off St. Augustine, St. Johns Co. (DMNH 107732); 6 spec., 6.4 x 3.9, 5.5 x 2.6, 5.5 x 2.6, 6.5 x 3.0, 6.8 x 2.8 & 4.1 x 2.2 mm, ex batfish in 40–46 m, 80–97 km E of Ponte Verde, St. Johns Co., H.G. Lee! 12 Mar 1998 (H.G. Lee coll.); 4 spec., 8.3 x 3.6, 8.6 x 4.2, 7.8 x 3.3, 7.1 x 3.2 mm, ex batfish in 48 m, off Brevard Co. (DMNH 213237); 1 spec., 8.2 x 3.7 mm, Cape Canaveral, Brevard Co., M. Williams! 13 Mar 1982 (USNM 900107); 2 spec., 9.0 x 3.9 & 8.9 x 3.7 mm, Cape Canaveral, Brevard Co., J. Tucker! (USNM 900108); 3 spec., 6.7 x 2.9, 6.8 x 3.0 & 7.6 x 3.3 mm, in 37–55 m, WOE Radio towers to Breakers Hotel, Palm Beach, Palm Beach Co. (UF 228736); 2 spec., 7.3 x 3.4 & 6.3 x 3.0 mm, in 91–107 m, off Palm Beach, Palm Beach Co. (UF 262282); 2 spec., 6.4 x 2.9 & 7.7 x 3.3 mm, in 91–107 m, off Palm Beach, Palm Beach Co. (UF 262285); 1 spec., 6.7 x 3.0 mm, in 37 m, S of Palm Beach Pier to N of Breakers Hotel, Palm Beach, Palm Beach Co., McGinty! 12 May 1951 (UF 185925); 1 spec., 7.6 x 3.4 mm, in 37 m, off Breakers Hotel, Palm Beach, Palm Beach Co., McGinty! 8 Mar 1951 (UF 222798). South Carolina. 1 spec., juvenile, in 34 m, LMRS Sta. MS06 voucher specimen, 32 ° 49 ' 30 "N, 078° 39 ' 48 "W, 25 May 1981 (USNM 843077) North Carolina: 2 spec., 7.0 x 3.2 & 4.3 x 2.7 mm, in 46 m, off Charleston, Charleston Co., 32 ° 19 ' 42 ''N, 079°09' 36 ''W, L. O. Campbell! (ANSP 354097).

Range and habitat. North Carolina; South Carolina; E Florida; Florida Keys; W Florida; and off Louisiana. It has been reported from 24–183 m, but more commonly in 30–55 m, based on data label information.

Description. Shell small (to 10.1 mm) stoutly fusiform, glossy, truncated anteriorly; aperture narrow; up to about 9 convex whorls; body whorl approximately 64 % of total length. Protoconch conical, of approximately 3 smooth whorls; tip of the first is partially immersed in the second. Axial sculpture of sigmoid to almost straight ribs reduced or absent in sulcus near suture, most prominent and widest, sometimes almost knob-like on whorl periphery, then evanescing on the shell base below periphery, sometimes persisting to the anterior fasciole. Ribs and rib crests narrowest in the sulcal region where ribs are recurved; ribs broaden at periphery where crests are rounded. Ribs number 8–10 on penultimate and 6–10 on the body whorl to the varix. Axial growth striae present on shell surface, recurved in the anal sulcus. Varix cup handle-like, curved slightly at shoulder; located just behind the anal sinus. Anal sinus on shoulder adjacent to suture, deep, U-shaped, offset from the shell axis by parietal callus; inner edge of sinus flared in mature specimens. Spiral sculpture of microscopic ridges just below the periphery of the body whorl; well-defined ridges anteriorly and on anterior fasciole. Outer lip thin, projecting out from the varix; sometimes with 1–2 thin axial ribs; viewing the shell laterally, lip edge forms a low arc beginning at and congruent with anterior side of anal sinus to the stromboid notch; stromboid notch shallow. Inner lip margined, erect and thicker anteriorly, thinner on parietal wall, with a thick callus posteriorly. Successive layers of deposition visible on edge of thicker portions of the lip, especially in more mature specimens. Anterior canal short, open, unnotched. Anterior fasciole not swollen; with 6–8 spiral ridges. Color shell base usually a light golden brown, most frequently with a narrow to broad white band mid-whorl; sometimes with a narrow dark band just above.

Remarks. Taxonomy. Douglassia bealiana  has the combination of characteristics that are unique to Douglassia  : a cup-handle-like varix, axial ribs reduced or absent in the sulcus, a smooth 3 -whorl protoconch, and absence of spiral sculpture except on the shell base. Variability. The degree of obliqueness of the ribs varies among specimens. It is particularly strong in the holotype, but nearly straight in some variants. The average length of 101 measured specimens is 6.83 mm (2.7–9.9 mm) and the average W/ L ratio  is 0.462 for the same group. The color pattern varies from light to dark golden brown with or without a narrow or broad white band and with or without a thin brown band above the white band. The brown band usually appears only between ribs. Identification. Douglassia bealiana  is similar in appearance to Cerodrillia girardi, Lyons 1972  but smaller in size (average total length of 6.83 versus 7.89 mm). It is easily distinguished by its more oblique and narrower ribs, white spiral peripheral band, and less inflated body whorl. From Cerodrillia ambigua  , new species it differs in possessing sigmoid, not straight, ribs, in the presence of a narrow spiral color band on the whorl periphery, and its smaller size (average total length of 6.83 versus 9.12 mm). From Cerodrillia occidua  , new species it differs in base color (light golden brown versus white, and its smaller size (average total length of 6.83 versus 11.39 mm).