''Tomigerus clausus'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of air-breathing

land snail A land snail is any of the numerous species of snail that live on land, as opposed to the sea snails and freshwater snails. ''Land snail'' is the common name for terrestrial gastropod mollusks that have shells (those without shells are known as ...

, a

terrestrial Terrestrial refers to things related to land or the planet Earth. Terrestrial may also refer to: * Terrestrial animal, an animal that lives on land opposed to living in water, or sometimes an animal that lives on or near the ground, as opposed to ...

pulmonate Pulmonata or pulmonates, is an informal group (previously an order, and before that a subclass) of snails and slugs characterized by the ability to breathe air, by virtue of having a pallial lung instead of a gill, or gills. The group includ ...

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

mollusk Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...

in the family

Odontostomidae Odontostomidae is a taxonomic family of medium-sized to large, air-breathing, tropical and sub-tropical land snails, terrestrial pulmonate gastropod molluscs in the superfamily Orthalicoidea.Breure A. S. H. & Romero P. (2012). "Support and su ...

Distribution

This species occurs in

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

Anatomy

The anatomy of ''Tomigerus clausus'' was examined by

Harold Heath Harold may refer to: People * Harold (given name), including a list of persons and fictional characters with the name * Harold (surname), surname in the English language * András Arató, known in meme culture as "Hide the Pain Harold" Arts ...

in 1914. The

mantle A mantle is a piece of clothing, a type of cloak. Several other meanings are derived from that. Mantle may refer to: *Mantle (clothing), a cloak-like garment worn mainly by women as fashionable outerwear **Mantle (vesture), an Eastern Orthodox ve ...

has more highly thickened margins and more glandular epithelium than in the genus'' Anostoma'', extending throughout the

body whorl The body whorl is part of the morphology of the shell in those gastropod mollusks that possess a coiled shell. The term is also sometimes used in a similar way to describe the shell of a cephalopod mollusk. In gastropods In gastropods, the b ...

of the shell to the region adjacent to the

aperture In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture and focal length of an optical system determine the cone angle of a bundle of rays that come to a focus in the image plane. An opt ...

. It thus terminates at the point where the

ureter The ureters are tubes made of smooth muscle that propel urine from the kidneys to the urinary bladder. In a human adult, the ureters are usually long and around in diameter. The ureter is lined by urothelial cells, a type of transitional epit ...

bends abruptly upon itself. The external openings of the ureter and intestine occupy the usual positions on the right side, and from this point they pursue a course parallel to the external surface of the body, in close contact with the

mantle cavity The mantle (also known by the Latin word pallium meaning mantle, robe or cloak, adjective pallial) is a significant part of the anatomy of molluscs: it is the dorsal body wall which covers the visceral mass and usually protrudes in the form of ...

. The ureter bends sharply upon itself at the termination of the mantle cavity, and, dorsally placed with reference to this chamber, proceeds anteriorly to unite with the forward extremity of the kidney. The body of the kidney is a compact, sac-like body consisting, as usual, of highly folded glandular epithelium confined, in the posterior half of the organ, to the outer face. The

pericardium The pericardium, also called pericardial sac, is a double-walled sac containing the heart and the roots of the great vessels. It has two layers, an outer layer made of strong connective tissue (fibrous pericardium), and an inner layer made of ...

is in contact with this glandular section throughout its entire length, but is scarcely more than half as extensive. A pericardial opening was not observed. It may be added that the kidney is placed dorsally with reference to the pericardium. There are no special features of the digestive system of ''Anostoma depressum''. The reproductive system, considering that the gonad is in a highly quiescent state, is comparatively large and more compact than in ''Anostoma''. The gonad consists of several slender diverticula, located in the apical whorls of the visceral mass. These contain primitive sex cells undifferentiated into sperm and ova. The

hermaphroditic duct In reproductive biology, a hermaphrodite () is an organism that has both kinds of reproductive organs and can produce both gametes associated with male and female sexes. Many Taxonomy (biology), taxonomic groups of animals (mostly invertebrate ...

extends ventrally, close to the

columella Lucius Junius Moderatus Columella (; Arabic: , 4 – ) was a prominent writer on agriculture in the Roman Empire. His ' in twelve volumes has been completely preserved and forms an important source on Roman agriculture, together with the wo ...

, and shortly before entering the accessory glands it attaches to a slender pear-shaped organ, possibly a seminal vesicle, consisting of upwards of ten small diverticula imbedded in a muscular sheath. These are empty and give no sign of glandular activity. The accessory glands are voluminous though inactive organs, though several lobes give them a much greater dorso-ventral thickness. The duct leading from the accessory glands becomes considerably widened near its proximal extremity, and possibly functions as a shell gland. As in ''Anostoma'', the duct from the seminal receptacle springs from this point, and, as a slender canal, proceeds to the spacious sack situated in close proximity to the accessory glands. The

vas deferens The vas deferens or ductus deferens is part of the male reproductive system of many vertebrates. The ducts transport sperm from the epididymis to the ejaculatory ducts in anticipation of ejaculation. The vas deferens is a partially coiled tube ...

, likewise, unites with the penis some distance from its distal extremity, thus forming a flagellum. No penis retractor has been discovered in this region. On the other hand, several strands attaching to the penis sheath in the neighborhood of the outer opening may operate as retractors.

References

This article incorporates public domain text from reference. Heath H. 1914. ''The anatomy of two Brazilian land-shells, Anostoma depressum and Tomigerus clausus''
Proceedings of the Academy of Natural Sciences of Philadelphia, 65688
692
plate 31
913

External links

{{DEFAULTSORT:Tomigerus Clausus Odontostomidae Gastropods described in 1827