THE NAUTILUS 105(3):81-91, 1991
Lamellitrochiis, a New Genus of Solariellinae
(Gastropoda: Trochidae), with Descriptions of
Six New Species from the Western Atlantic Ocean
Janie§ F. Quinii, Jr.
Florida Mariiif Research Institute
Department of Natural Resources
100 Eighth Avenue. S E
St. Petersburg, PL 33701-5095, L'SA
Lamellitrochiis new genus is erected for eight western Atlantic
species of Solariellinae. The genus is distinguished by having
conicoturbinate shells with angular whorls; strong, usually la-
mellif arm axial riblets that usualK become obscure or are absent
on last v\horls; strong subsutural angulation bearing rounded,
conical, or lamellate tubercles; strong, smooth to tuberculate
peripheral carina; strong, circumbasal carina; intritacalx-like
outer shell layer; usualK niicropustules on earl\ whorls; and
radula lacking a lateroniarginal plate Included in Lamellitru-
chus are the type species, Margarita laniellosa Verrill & Smith,
1880; Solariclla pourtalesi Clench & Aguayo, 19.39; and six new
species: L. inceratus, L. carinatiis. L. sitavis. L. filosiis. L.
fenestratus, and L. bicoronatus.
Key words: Gastropoda; Trochidae; Solariellinae, Lamellitru-
chits ; systematics; new species.
The Solariellinae Powell, 1951, was erected for trochid
genera having short radulae with reduced numbers of
marginal teeth (usually 10 or fewer pairs per row). More
recent work has shown that features of the external anat-
omy (a broad, fringed snout; propodium with lateral
horns; reduced epipodium) are also characteristic of the
subfamily (Fretter & Graham, 1977; Herbert, 1987;
Hickman & McLean, 1990). Although the subfamily is
well defined, Herbert (1987) has shown that animals with
similar shell characters can have different radulae, and
that assignment of these species to genera based solely
on shell characters is sometimes inadvisable. Indeed, this
is reflected in the low number of extant genera (10)
recognized at present (Hickman and McLean, 1990).
Despite the obvious convergence of shell characters of
many species, some species defy ready assignment to
existing genera. Eight such species occur in the western
Atlantic Ocean, and the genus Lamellitrochiis is pro-
posed to include those taxa.
Institutional abbreviations used in this paper are as
follows; DMNH (Delaware Museum of Natural History,
Wilmington. Delaware); FSBC I (Florida Marine Re-
search Institute, St. Petersburg, Florida); MNHN (Mu-
seum National d'Histoire Naturelle, Paris); MORG (Mu-
seu Oceanografico da Fundacao Universidade do Rio
Grande, Rio Grande, RS, Brazil); UF (Florida Museum
of Natural History, L'niversit\ of Florida, Gainesville,
Florida); UMML (Rosenstiel School of Marine and At-
mospheric Science, University of Miami, Miami, Flori-
da); and L'SNM (National Museum of Natural History,
Smithsonian Institution, Washington, DC).
Family Trochidae Rafinesque, 1815
Subfamily Solariellinae Powell, 1951
Genus Lamellitrochiis Quinn new genus
Margarita: Verrill & Smith in N'errill, 1S80;.392 (partim), Ver-
rill, 1880:.378 (in 1880-1881); 1881:406; 1882:530, .531
ipartim): 1885:527; Dall, 1881:40 (partim).
Margarita (Solariclla): Dall, 1889a:378-382 (partim); 1889b:
164 (partim): 1903:164 (partim). Pilsbry. 1890:307-3.30
Solariclla: DaW. 1927:128-130 (par(im); Johnson, 193471 (par-
tim): Clench & Aguayo, 1939:190, 191; Rice & Kornicker,
1965:117 (partim). Porter, 1974:21 [partim): .Abbott, 1974:
41 (partim): Treece, 1980:5.59,
Solariclla (Machacroplax): .-Abbott, 1974:40 (partim).
Solariclla (Solariclla): Quinn, 1979:37-42 (partim).
Diagnosis: Shell small (usualK <10 mm); subsutural
angulation tuberculate; peripheral carina prominent,
smooth to tuberculate; umbilicus broad; sharp, usually
lamellate axial riblets on early teleoconch whorls; mi-
crosculpture usually of irregular pustules; intritacalx-like
outer shell layer; and oblique, circular to ovate aperture.
Description: Shell small, largest attaining height of about
10 mm but usualK less than 5 mm, conicoturbinate,
umbilicate, nacreous under thin intritacalx and white
porcelaneous layers. Whorls tubular, shouldered, periph-