Overview

Comprehensive Description

Description

Original Description: F. M. Bayer: 'New Pleurotomariid Gastropods from the Western Atlantic, with a Summary of the Recent Species'; Bulletin of Marine Science, Vol. 15 (1965).

The holotype is in the National Museum of Natural History, Smithsonian Institution, Washington DC; USNM 655930.

Synonomies:

Perotrochus midas Bayer, 1965; Fretter, 1966; Cross & Morrison, 1971; Abbott, 1974; Okutani, 1987; Harasewych, Pomponi & Askew, 1988; Anseeuw & Goto, 1996

Pleurotomaria midas Abbott & Dance, 1982

Pleurotomaria (Perotrochus) midas Hickman, 1984

Bayerotrochus midas Williams, Karube & Ozawa, 2008; Anseeuw, 2010; WoRMS, 2010

Videos of Bayerotrochus midas

GenBank - Bayerotrochus midas

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© Gillevet, Emilia

Source: Pleurotomariidae

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Slit shells are named for the narrow, open slit in the last part of the body whorl, on each side of which is an internal gill. Bayerotrochus midas, King Midas's Slit Shell, is the deepest dwelling pleurotomariid snail in the western Atlantic. This species inhabits steep rocky walls at depths ranging from 1,400 to 2,800 ft, and ranges from southern Georgia (USA) throughout the Bahamas and into the Caribbean. The southern limits of this species are still poorly known, and the known range will likely expand considerably with additional deep water sampling throughout the Caribbean and along the northern coast of South America. Where pleurotomariids have been thoroughly studied using research submarines, three species were found to occur along steep-walled coasts. However, each of the three species has a narrow range depth range that does not overlap with the other two species.

Like all pleurotomariids, Bayerotrochus midas feeds primarily on sponges, but has occasionally been observed eating soft corals and stalked crinoids. Despite their thin, fragile shells, pleurotomariids are able to suvive attacks by predators by producing an opaque, viscous secretion when disturbed. Large quantities of this secretion are produced rapidly by the paired hypobranchial glands that occur on each side of the slit.

The outer calcitic layer of the shell is so thin as to be translucent; light passing through it is reflected off the inner, nacreous layer producing a shiny golden color that inspired the specific epithet “midas.” The genus Bayerotrochus was named to honor the late Dr. F. M. Bayer, who discovered and described this species, in recognition of his many contributions to the study of western Atlantic invertebrates, especially corals and mollusks.

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Jerry Harasewych

Source: EOL Rapid Response Team

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Distribution

Smithsonian Collection Specimens

Catalog Number

Country

State

Locality

Geo Decimal Latitude

Geo Decimal Longitude

Depth, minimum (meters)

Depth, maximum (meters)

1120933

United States

Florida

Portales Terrace, Jordan Sinkhole, west lobe, along the underside of an overhanging rim of northwest rock wall

24.272855

-81.036565

427

1069299

United States

Georgia

31.315

-78.85917

1738

1813

1072425

Bahamas

San Salvador, off Bone Fish Bay

24.08639

-74.55528

749

1072406

Bahamas

New Providence Island, West of

25.05917

-77.53667

757

768

1072411

Bahamas

Great Inagua Island, off Middle Point

21.02917

-73.72972

774

1072422

Bahamas

Eleuthera Island, north Eleuthera, west of Egg Island

25.46417

-76.91028

718

1072423

Bahamas

Long Island, west of South Point

22.84167

-73.88333

625

1072426

Bahamas

San Salvador Island, west of Riding Rock

24.05861

-74.55333

711

777

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© Gillevet, Emilia

Source: Pleurotomariidae

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Physical Description

Diagnostic Description

Description.- The shell is large, thin, broadly turbiniform, with bluntly rounded apex (Figs. 2, 3). Whorls 9% including the protoconch, which consists of one glassy, translucent, unsculptured whorl faintly delimited teleoconch is turbiniform, with rapidly expanding whorls and a spire angle of 97°, but after about 2 Y2 turns the whorls flare broadly and become practically planispiral (Figs. 7-9). The result is a shell suggestive of Eotomaria (d. Eotomaria canalifera Ulrich as illustrated by Knight et al.,1960: 205, fig. 118, 7) but even more depressed and with a differently placed slit and fasciole (Fig. 8, a). Subsequently, the coiling assumes a steeper angle so the shape of the shell becomes lenticular (Fig. 8, b) and resembles the Mesozoic Obornella (d. Obornella plicopunctata as illustrated by Knight et al., 1960: 216, fig. 131, la-lb). From about the fourth through the sixth whorls, the periphery is prominent and flattened, standing out as a squarish carina resembling the milled edge of a coin (Fig. 8, a). The shell becomes cyrtoconoid as it grows larger (Fig. 8, c), and at full size resembles the large, thin-shelled species of Perotrochus (e.g., africanus and teramachii), but with a blunt spire (Fig. 4). This condition is reminiscent of the Triassic Eymarella, in which the early whorls are discoidal, the later ones trochoid aI, producing a blunt apex (cf. Eymarella scalariformis as shown by Knight et al., 1960: 216, fig. 130, 3). The last four whorls are inflated, with a moderately convex ramp, steeply sloping, almost vertical sides, and bluntly angular periphery; the angle of the spire is 90° here. The base is convex, narrowly excavate in the umbilical region but not perforate. The aperture is ovate, the outer lip with a moderately deep sinus extending about Y4 of the peripheral circumference. The slit and fasciole are located approximately midway between suture and periphery, but because of the convex base they lie rather high on the body whorl and form an obscure shoulder separating the more or less convex ramp from the steep, almost straight sides. The columellar margin of the aperture is only slightly thickened, the sigmoid twist is moderate, and the pearly callus over the umbilical region is of very limited extent. The sculpture consists of spiral cords and axial riblets which produce a beaded surface. Below the fasciole, the axial component is practically vertical, crossing the spirals at right angles to produce beads that are almost square, whereas above the fasciole the axial element is strongly prosocline so that the collabral riblets cross the spirals obliquely and produce beads that are elongated along the axis of the spirals. On the body whorl there are about 3'0 spiral cords above the fasciole and about 18 below. On the eighth whorl there are 15 spirals above and 9 below the fasciole. They increase in number by dichotomy so they tend to occur in pairs. On the base there are about 75 spiral cords intersected by collabral growth riblets, resulting in a weakly beaded surface. The fasciole is slightly concave and marked by three faint cords, of which the central one is strongest, and close-set raised lunules. Both upper and lower edges of the slit are flared outward so that the fasciole is bordered by raised keels after the slit closes. The fasciole originates on the upper surface of the first post-nuclear whorl, moving to a lateral position as the space between suture and fasciole widens to form the ramp (Fig. 6). As the whorls become flattened, the fasciole comes to lie on the outer face of a broad, spiral elevation between the suture and the raised periphery. As the slope of the whorls increases, the fasciole moves to its definitive position at the shoulder. The ground color of the shell is golden yellow above, with the iridescence of the nacreous layer showing through the translucent porcellaneous layer. At about the fifth whorl, a darker yellow spiral band appears just below the suture, becoming broader and more distinct on the following whorl, then more diffuse. Its darker lower edge moves to the margin of the fasciole as the shell enlarges, forming an orange line. A similar orange marginal line appears along the lower edge of the fasciole at about the seventh whorl. Axial streaks of pinkish orange appear on the seventh and eighth whorls, progressively darkening as the shell increases in size. On the body whorl a pinkish general suffusion appears, giving the shell an exceptionally beautiful pinkish-gold coloration. The base is pinkish cream with darker streaks following the growth lines. The interior of the aperture is lined with iridescent nacre except on the parietal wall where the color of the base shows through a transparent glaze. A thin orange line follows the edge of the nacreous layer along the rim of the slit and around its closure. There are traces of an extremely thin, horny periostracum remaining on many parts of the outer surface.” (Bayer, 1965)

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© Gillevet, Emilia

Source: Pleurotomariidae

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Type Information

Holotype for Bayerotrochus midas (Bayer, 1966)
Catalog Number: USNM 655930
Collection: Smithsonian Institution, National Museum of Natural History, Department of Invertebrate Zoology
Preparation: Dry
Year Collected: 1965
Locality: Berry Island, NW Providence Channel, 15 Miles NW Of Great Stirrup Cay, Bahamas, Caribbean Sea, North Atlantic Ocean
Depth (m): 595 to 711
Vessel: Gerda R/V
  • Holotype: 1966. Bull. Mar. Sci. 15(4): 737-796.
Creative Commons Attribution 3.0 (CC BY 3.0)

© Smithsonian Institution, National Museum of Natural History, Department of Invertebrate Zoology

Source: National Museum of Natural History Collections

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Ecology

Habitat

Depth range based on 18 specimens in 1 taxon.
Water temperature and chemistry ranges based on 15 samples.

Environmental ranges
  Depth range (m): 427 - 1775.5
  Temperature range (°C): 8.565 - 14.575
  Nitrate (umol/L): 7.981 - 27.109
  Salinity (PPS): 35.052 - 35.995
  Oxygen (ml/l): 3.130 - 3.998
  Phosphate (umol/l): 0.691 - 1.817
  Silicate (umol/l): 3.336 - 19.178

Graphical representation

Depth range (m): 427 - 1775.5

Temperature range (°C): 8.565 - 14.575

Nitrate (umol/L): 7.981 - 27.109

Salinity (PPS): 35.052 - 35.995

Oxygen (ml/l): 3.130 - 3.998

Phosphate (umol/l): 0.691 - 1.817

Silicate (umol/l): 3.336 - 19.178
 
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Wikipedia

Bayerotrochus midas

Bayerotrochus midas, common name King Midas's slit shell, is a species of sea snail, a marine gastropod mollusk in the family Pleurotomariidae.[1]

Description[edit]

The size of the shell varies between 60 mm and 128 mm.

Distribution[edit]

This species occurs in the Caribbean Sea and the Gulf of Mexico; in the Atlantic Ocean off the Bahamas.

References[edit]

  1. ^ a b Bayerotrochus midas (Bayer, 1966).  Retrieved through: World Register of Marine Species on 13 March 2013.
  • Williams S.T., Karube S. & Ozawa T. (2008) Molecular systematics of Vetigastropoda: Trochidae, Turbinidae and Trochoidea redefined. Zoologica Scripta 37: 483–506
  • Rosenberg, G., F. Moretzsohn, and E. F. García. 2009. Gastropoda (Mollusca) of the Gulf of Mexico, Pp. 579–699 in Felder, D.L. and D.K. Camp (eds.), Gulf of Mexico–Origins, Waters, and Biota. Biodiversity. Texas A&M Press, College Station, Texas.
Creative Commons Attribution Share Alike 3.0 (CC BY-SA 3.0)

Source: Wikipedia

Unreviewed

Article rating from 0 people

Default rating: 2.5 of 5

Disclaimer

EOL content is automatically assembled from many different content providers. As a result, from time to time you may find pages on EOL that are confusing.

To request an improvement, please leave a comment on the page. Thank you!