E. F. Garcia 
Novapex 12(3-4): 57-62,10 octobre 2011 
A new species of Mitra ( Fusimitra ) (Gastropoda: Mitridae) from the 
northwestern Gulf of Mexico 
Ernilio F. GARCIA 
115 Oak Crest Dr. 
Lafayette, LA 70503 
Efg21 12@louisiana.edu 
KEYWORDS. Mitridae, Mitra s.s., new species, Gulf of Mexico 
ABSTRACT. A new species of Mitra (Fusimitra ) inhabiting the pinnacles off the Louisiana coast 
is described and compared with Mitra (F.) antillensis Dali, 1889, its most similar congener. 
INTRODUCTION 
On the continental shelf off the Louisiana and 
Texas coasts there is a sériés of banks or “pinnacles” 
peculiar to the northwestern Gulf of Mexico. Their 
geological history indicates that at one time, when the 
sea- level was much lower, these were shallow 
intertidal areas where coral grew. Nowadays these 
banks, which arise abruptly from a soft, muddy 
bottom to 20 to 90 m from the surface, hâve a summit 
composed of calcareous rubble, a product of their 
former coral fauna. These formations hâve been 
discussed by Williams (1951), Stetson (1951), 
Goedicke (1955) and others; however, their molluscan 
fauna was not seriously addressed until Parker & 
Curray (1956), who listed a large number of species 
and noted their similarity to the shallow-water 
Caribbean fauna ( Idem : 2428). The list of the rich 
molluscan fauna of the pinnacles was later expanded 
by a number of expéditions supported by grants, 
mostly from the National Science Foundation, to the 
Biology Department at the University of Louisiana at 
Lafayette. They hâve been reported elsewhere (Garcia, 
2000, 2002, 2007, 2008, 2010; Garcia & Lee, 2002, 
2003, 2004). 
The new species of Mitra (Fusimitra ) described 
herein seems to be confmed to the top of the offshore 
pinnacles discussed above. Although there hâve been 
dredging cruises in the northeastern quadrant of the 
Gulf of Mexico south to Dry Toitugas, and in the 
southeastern quadrant at Bahia de Campeche, Mexico, 
no specimens of the new species hâve been collected 
in those areas. The 10 specimens that comprise the 
type material were collected during seven expéditions 
expanding a period of 11 years, from 2000 to 2010. 
Only two specimens hâve been collected alive. 
Ail cruises were done on the R/V Pélican, a 
research vessel administered by the Louisiana 
Universities Marine Consortium (LUMCON) using a 
box dredge roughly 3 ft. by 3 ft. by 1 ft. 
Abbreviations 
BMSM: Bailey- Matthews Shell Muséum, Sanibel, 
Florida, USA. 
CMT: Charlotte M. Thorpe collection, Jacksonville 
Beach, Florida, USA. 
EFG: author’s collection 
FF: Frank Frumar collection, Kirkwood, Missouri, 
USA. 
SBMNH: Santa Barbara Muséum of Natural History, 
Santa Barbara, California, USA. 
TCWC: The Texas Cooperative Wildiife Collection, 
Texas A & M University, College Station, Texas, 
USA. 
USNM: United States National Muséum, Washington, 
D.C., USA 
SYSTEMATICS 
Family MITRIDAE Swainson, 1829 
Genus Mitra Lamarck, 1798 
Type species: Voluta episcopalis Linnaeus, 1758 (= V. 
mitra Linnaeus, 1758 [ICZN, 1969]) by subséquent 
désignation of Montf'ort (1810: 543). 
Mitra ulala n. sp. 
Figs. 1-15 
Type material. Holotype (Figs. 1-3) USNM 1155049, 
28°05.95'N, 91°01.34'W, 69-68 m, length 30.5mm. 
width 10.3 mm; paratype 1 (Fig. 4) USNM 1155050, 
28°06.217N, 91°070'W, 75-65 m, length 21.9 mm, 
width, 8.75 mm; paratype 2 USNM 1155051, 
28 U 06.71'N, 91°02.50'W, 57-71 m, length, 22.o mm, 
width 8.7 mm; paratype 3. TCWC 4-5247, 
28°05.76'N, 91°01.15'W -, 64.7-62.1 m, length 25.6 
mm, width 9.2 mm; paratype 4 (Fig. 7) USNM 
1155052, 27°58.01'N 92° 35.67'W, 75-85 m, length 
27.1 mm, width 8.4 mm; paratype 5 (Fig. 8) BMSM 
17952, 28° 6.2 UN. 91° 2.23’W, 99.3 m, length 21.9 
mm, width 8.0 mm; paratype 6 (Figs. 5-6) SBMNH 
149759. 28°38.16'N, 89°33.19'W, 60-70 m, length 
18.8 mm, width 7.6 mm; paratype 7 (Fig. 9) EFG 
24308, 28°5.85’N, 91°1.28’W, 68.3 m, length 32.2 
mm, width 10.8 mm; paratype 8 (Figs. 10-11) EFG 
23177, 27° 59.141 'N; 91° 38.832’W, 91-65 m, length 
23.2 mm, width 7.8 mm; paratype 9 (Figs. 12-15) 
CMT, 28°05.552'N, 91°00.82'W, 63-64 m, length 23.7 
mm, width 8.7 mm. 
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