Scaphella (Scaphella) garciai n. sp. (Gastropoda: Volutidae: Scaphellinae) a new volute from off Yucatan, Mexico

2007·1.5 MB·

P. Bail Novapex 8 (2): 75-78, 10 octobre 2007
Scaphella (Scaphella) gardai n.sp.
(Gastropoda: Volutidae: Scaphellinae)
a new volute from off Yucatan, Mexico
Patrice BAIL
2 Square La Fontaine, 75016 Paris France.
[email protected]
KEYWORDS. Gastropoda, Scaphella, Volutidae, new species, Yucatan, Mexico.
ABSTRACT. Scaphella (Scaphella) gardai n. sp. is described on the basis oftwo spécimens, one
collected off San Augustine, Florida. Différences between the new species and its congeners are
established.
INTRODUCTION polytypic Scaphella dubia (Broderip, 1827) in its
subgeneric status.
Recently checking his collection, Emilio Fabiân On the contrary, Scaphella s.s. includes species with a
Garcia pointed out to me a spécimen of the genus strong shell, a more or less pronounced fasciole, 2 to
Scaphella which seemed to be a previously 4 well-defined columellar plaits, mostly a dense spiral
undescribed species. The spécimen was given to him pattern ofdots or bands, and a Y-shaped radula with
by Edith Mugridge, a well-known dealer and shell orwithout vestigial side cups.
collector from Sanibel Island, Florida. Ms. Mugridge Based upon thèse shell characters only, Scaphella
obtained many of her spécimens from a number of gardai can be temporarily placed into Scaphella s.s.,
shrimpers who worked the east coast of Florida and pending additional anatomical information.
the Yucatan waters, and the true locality of the
spécimen in question became uncertain. SYSTEMATICS
Taxonomic placement (in Bail & Shelton, 2001 Family VOLUTIDAE Rafinesque, 1815
)
Subfamily SCAPHELLINAE H. and A. Adams,
The genus Scaphella comprises several related 1858
polytypic taxa, which hâve been the subject of GenusScaphella Swainson, 1832
controversial classification at both the generic and Subgenus: Scaphellas.s.
spécifie ranks. Type species: Voluta juniona Lamarck, 1804, by
Based upon the shape ofthe radula, Pilsbry & Olsson subséquent désignation (Herrmannsen, 1848: 423)
(1953) splitScaphella into three gênera:
-Scaphella s.s. with but a single long narrow cusp; Scaphella (Scaphella)gardai n. sp.
-Clenchina with a conic central cusp, flanked by two Figs 1-5, 12-14
minute accessory cusps (synonym Rehderia Clench,
1946); Type locality. Unknown
-Aurinia H. & A. Adams, 1853 with a pointed central
cusp and two well-developed side cusps. Range. Until now only collected from northeastern
Weaver & du Pont (1970) and Bayer (1971) Florida, USA (paratype).
downgraded those three gênera to a subgeneric rank
of Scaphella, pointing out the minor taxonomic Type material. Holotype ANSP 416213, length: 47.2
significance of their radular différence, especially mm, width: 15.9 mm mm. locality unknown (Figs 1-
between Clenchina and Scaphella s.s., both ofwhich 3). Paratype: K. & L. Sunderland collection, length
are now considered synonyms. 46.0 mm, width: 15.2 mm, taken in fish trap from 300
Though relegated into synonymy of Scaphella by meters depth offSt Augustine, Florida (Figs 4-5).
Emerson & Old,jr. (1979) and Poppe & Goto (1992),
mm
the subgenus Aurinia deserves to keep its subspecific Description. Shell small, up to at least 47.2 in
status: a chief feature, emphasized by Pilsbry & length, elongate fusiform with strong structure and
Olsson, is the thin callus covering the ventral side of polished surface. Protoconch dome-shaped, large, of
the shell, often incrusting a muddy deposit. 4.3 mm in diameter on holotype, with one smooth,
Additional characters such as a complète tricuspidate flattened whorl without visible calcarella. Transition
radula, light structure of the shell, lack of fasciole, protoconch/teleoconch sharp, marked by slightly
obsolète columellar plaits, and open pattern of concave dépression (Fig. 12). Teleoconch of three
irregularly spaced dots are sufficient to maintain the and a halfmoderately convex, narrow whorls. Surface
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I' M\n Scaphellagardai n.sp.
eniireK sculptured with numerous thin spiral cords bolotype to the Academy of Natural Sciences of
[ca 30-35 on penultimate whorl) crossed bj light Philadelphia(ANSP).
growth striae, ui\me l'ami reticulated appearance,
weakening on dorsum oflasl whorl (lig. 14). Suture Kcinarks. The first occurence of this taxon in
&
adpressed, underlined b> subsutural constriction literature has been pictured by K. L. Sunderland
forming well-marked concave ramp. Aperture (1992) but misidentifïed as Scaphella aguayoi
%
narrow, elongated, occupying 0.60 of total shell (Clench, 1940). This shell, selected as paratype, was
length. Outer lip thin. rapidly thickening below. dredged from 260 meters by Ted Yocius off St.
Columella straight, with three thin plicae; adapical Augustine, FL in 1971. The holotype was labelled off
plica strongest (Fig.13). Siphonal canal narrow, Contoy Light. Yucatan, 200 m deep. However, after
tapered. Fasciolc ill-defined. Shell coloration later investigations, no fishermen operating in the
yellowish-ivory without pattera. Yucatan waters hâve ever seen this shell. This
Animal and radula unknown. location seems erroneous ail the more that the overall
characters of S. gardai are closer to Florida
Comparison. In overall shell characters, the most Scaphella than to the known Yucatan species (S.
similar species to Scaphella gardai is Scaphdia contoyensis Emerson & Old. Jr, 1979 and S.
(Scaphella) gouldiana (Dali, 1889), which has the macginnorum Garcia & Emerson,1987).
saine nuclear structure and same spiral threads.
However, S. gouldiana has a broader ovate shell with REFERENCES
a short spire bearing 21-24 solid nodules; its
protoconch is slighty more elevated, the spiral Bail P. & Shelton D. N. 2001 Scaphella (Scaphella)
sculpture on the body whorl is weaker , and the gaudiati (Gastropoda: Volutidae: Scaphelinae), a
subsutural band is flat and hardly distinguishable. new volute from the Caribbean Sea. Novapex
Two equal plicae plus an abapical smaller and the 2(4): 137-140.
présence of a pattern of spiral brown bands in S. Bayer, F. M. 1971. New and unusual molluskscollectedby
gouldiana precludes also any confusion (Figs 8-9). the R/VJohn Elliott Pillsburyand R/V Gerda in the
A still undescribed small-sized Scaphella from deep tropical WesternAtlantic. In: Bayer, Frederick M. and
water offKey West, close to S. gouldiana shares with Gilbert L. Voss, Eds. Studies in TropicalAmerican
Mollusks. UniversityofMiami Press, Coral Gables,
S. gardai the same protoconch shape and, on the
Florida. pp. 111-236.
body whorl, the same spiral sculpture and lack of Dickson A. 1996. Dubious Volutes, Part 1-4, OffSea
pattern. However, its smaller size (average length andShore 19(1-4): 1.
under 40 mm), strongly angled whorls, short Emerson W. K. & Old Jr W. E. Scaphella
triangular spire bearing a spiral row of prominent contoyensis, a new volutid (Gastropoda) from
axial nodules extending onto the first two-third ofthe East Mexico. TheNautilus 93(1): 10-14.
body whorl, and four, strongly developed columellar
Herrmannsen A. N. 1848 [1846-1852]. Indices
plaits are quite différent (Dickson, 1996) (Figs 10- Generum Malacozoorum Primordia, vol. 2: 1-717.
11).
Scaphella neptunia (Clench & Aguayo, 1946) is a PilsCbarsyseHl.,A2.v&olsO.lsson A.A 1953. Materials fora
small species with a somewhat similar outline, but it Revision ofEast Coast and Floridan Volutes. The
differs by having a larger protoconch bearing a
Nautilus (67) 1: 1-13.
prominent calcarella, a shorter spire with one less
Poppe, G. T. and Y. Goto. 1992. Volutes.
whorl, a body whorl with strong spiral grooves and a LTnformatore Piceno Ed., Ancona. 348 pp.
pattern ofspiral rows ofbrownish axial dashes (Figs &
Sunderland K. L. 1992. Carribean Volutidae.
6-7).
American Conchologist20(2): 14.
&
Weaver, C. S. J. du Pont. 1970. TheLiving
Etymology. This species is named for Emilio Fabiân Volutes, a Monograph ofthe Récent Volutidae of
Garcia, the well-known conchologist who first drew the World, Delaware Muséum ofNatural History,
attention to this taxon, and who has donated the Greenville, USA, 375 pp.
Figures 1-11
1-5. Scaphella (Scaphella)garda n.sp.
1-3. Holotype, locality unknown, 47.2 x 15.9 mm; 4-5. Paratype, offSt Augustine, Florida, USA, 300 m, 46.0 x
15.9 mm.
6-7. Scaphella (Scaphella) neptunia, 750-800 m, Pedro Bank, southeastern Jamaica. 39.8 x 16.0 mm;
8-9. Scaphella (Scaphella)gouldiana, 500-600m, offKey West, Florida, USA. 60.0 x 24.1 mm;
10-11. Scaphella (Scaphella) sp., 500-600 m, offPalm Beach, Florida, USA. 38.6 x 15.1 mm;
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P. Bail NOVAPEX 8 (2): 75-78. 10 octobre 2007
77
mu
i' Scaphellagardai n.sp.
Figures 12-14
12-14. Scaphella (Scaphella)garda n.sp. 12. Protoconch. Black arrow on the transition protoconch /teleoconch;
13. Columellar plaits; 14. Surface sculpture.
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