Omalonyx convexus

Last updated

Omalonyx convexus
Omalonyx convexus.png
Orange color variety of Omalonyx convexus
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
(unranked):clade Heterobranchia
clade Euthyneura
clade Panpulmonata
clade Eupulmonata
clade Stylommatophora
clade Elasmognatha
Superfamily: Succineoidea
Family: Succineidae
Genus: Omalonyx
Species:O. convexus
Binomial name
Omalonyx convexus
(Heynemann, 1868)

Omalonyx convexus is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusc in the family Succineidae, the amber snails. This species of snail is found on emergent vegetation in lentic environments, and also submerged among macrophytes. [1]

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 sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. While these definitions may seem adequate, when looked at more closely they represent problematic species concepts. For example, the boundaries between closely related species become unclear with hybridisation, in a species complex of hundreds of similar microspecies, and in a ring species. Also, among organisms that reproduce only asexually, the concept of a reproductive species breaks down, and each clone is potentially a microspecies.

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. However, it is not always easy to say which species are terrestrial, because some are more or less amphibious between land and fresh water, and others are relatively amphibious between land and salt water.

Terrestrial animal animals living on land

Terrestrial animals are animals that live predominantly or entirely on land, as compared with aquatic animals, which live predominantly or entirely in the water, or amphibians, which rely on a combination of aquatic and terrestrial habitats. Terrestrial invertebrates include ants, flies, crickets, grasshoppers and spiders.

Contents

Distribution

The distribution of Omalonyx convexus includes Brazil. [1]

Description

Omalonyx convexus can be up to 4 cm in total length. [1] Tegument and mantle coloring varies between milky-white, orange and beige. [1] The tegument and mantle have irregularly sized and distributed blackish spots, which, depending on their quantity, can sometimes give the animal a dark gray appearance. [1] Beige was the most commonly observed coloring (Arruda & Thomé). [1] Because of their translucence, milky-white individuals sometimes display the same coloring as the substrate. [1] Because of its wide variability in color, Omalonyx convexus can be confused with other Omalonyx species: Omalonyx matheroni , Omalonyx pattersonae and Omalonyx unguis .

Mantle (mollusc) Part of the anatomy of molluscs

The mantle 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 flaps well beyond the visceral mass itself.

In biology, a substrate is the surface on which an organism lives. A substrate can include biotic or abiotic materials and animals. For example, encrusting algae that lives on a rock can be itself a substrate for an animal that lives on top of the algae.

<i>Omalonyx</i> genus of molluscs

Omalonyx is a genus of air-breathing land snails, terrestrial pulmonate gastropod molluscs in the family Succineidae, the amber snails. These snails are amphibious, living very close to water and moving around both on emergent plants and also on submerged aquatic plants.

The shell is translucent with a slightly amber tint, and it can be covered by the mantle to various extents. The shell was not completely covered by the mantle in any of the specimens observed by Arruda and Thomé. [1]

Gastropod shell part of the body of a gastropod or snail

The gastropod shell is part of the body of a gastropod or snail, a kind of mollusc. The shell is an exoskeleton, which protects from predators, mechanical damage, and dehydration, but also serves for muscle attachment and calcium storage. Some gastropods appear shell-less (slugs) but may have a remnant within the mantle, or the shell is reduced such that the body cannot be retracted within (semi-slug). Some snails also possess an operculum that seals the opening of the shell, known as the aperture, which provides further protection. The study of mollusc shells is known as conchology. The biological study of gastropods, and other molluscs in general, is malacology. Shell morphology terms vary by species group. An excellent source for terminology of the gastropod shell is "How to Know the Eastern Land Snails" by John B. Burch now freely available at the Hathi Trust Digital Library.

Beige colored Omalonyx convexus. Omalonyx convexus 2.png
Beige colored Omalonyx convexus.
Beige colored Omalonyx convexus with a darkish-gray appearance. Omalonyx convexus 3.png
Beige colored Omalonyx convexus with a darkish-gray appearance.

Ecology

Habitat

Arruda and Thomé found this species in both clean and polluted freshwater environments (polluted by household sewage), as well as on both natural and artificial substrates. [1] The habitat of Omalonyx convexus includes vegetation bordering ditches used for rice paddy irrigation, drainage ditches, floodplains, lakes, rivers and streams. The species was also found on the dry portion of a semi-submerged tree in a temporarily flooded location. [1] These snails are mainly seen on the macrophytes Eicchornia azurea , Salvinia auriculata , Pistia stratiotis and Eryngium species, but they were also found on artificial substrates such as canvas, cardboard, plastic bottles, tetra-pak boxes and styrofoam. [1]

Sewage Wastewater that is produced by a community of people

Sewage is a type of wastewater that is produced by a community of people. It is characterized by volume or rate of flow, physical condition, chemical and toxic constituents, and its bacteriologic status. It consists mostly of greywater, blackwater ; soaps and detergents; and toilet paper.

Floodplain Land adjacent to a stream or river which is flooded during periods of high discharge

A floodplain or flood plain is an area of land adjacent to a stream or river which stretches from the banks of its channel to the base of the enclosing valley walls, and which experiences flooding during periods of high discharge. The soils usually consist of levees, silts, and sands deposited during floods. Levees are the heaviest materials and they are deposited first; silts and sands are finer materials.

<i>Salvinia auriculata</i> species of plant

Salvinia auriculata is a species of plant in the Salviniaceae known by the common names eared watermoss, African payal, and butterfly fern. It is native to the Americas from Mexico south to Argentina and Chile. It is cultivated as an ornamental plant and it has become naturalized in the wild in some places.

Arruda & Thomé reported that the snails are found on different substrate areas during the course of the day, a behavioral adaptation to guard against desiccation, since apparently the temperature change influences their choice of habitat substrates. In the early morning (between 7 a.m. and 10 a.m.) and at the end of the afternoon (between 4 p.m. and 6 p.m.) during sunny days, the animals were observed on the stem and on the adaxial surface of the macrophyte leaves, on grasses in flooded areas and under adjacent vegetation on the banks of dikes and lakes. In this last case, they were well camouflaged, and it was very difficult to find them. During the hottest hours of the day (between 10 a.m. and 4 p.m.), they were found on flowers, roots, abaxial surface of leaves, and close to the base of macrophyte flowers. [1]

Desiccation tolerance refers to the ability of an organism to withstand or endure extreme dryness, or drought-like conditions. Plants and animals living in arid or periodically arid environments such as temporary streams or ponds may face the challenge of desiccation, therefore physiological or behavioral adaptations to withstand these periods are necessary to ensure survival. In particular, insects occupy a wide range of ecologically diverse niches and, so, exhibit a variety of strategies to avoid desiccation.

Feeding habits

Their diet is basically plant tissues, although pollen grains and non-vegetal food items (mites) were also found in their crop contents. [1]

Related Research Articles

Aquatic plant plant that has adapted to living in an aquatic environment

Aquatic plants are plants that have adapted to living in aquatic environments. They are also referred to as hydrophytes or macrophytes. A macrophyte is an aquatic plant that grows in or near water and is either emergent, submergent, or floating, and includes helophytes. In lakes and rivers macrophytes provide cover for fish and substrate for aquatic invertebrates, produce oxygen, and act as food for some fish and wildlife.

Siphon (mollusc) Anatomical structure which is part of the body of some aquatic molluscs

A siphon is an anatomical structure which is part of the body of aquatic molluscs in three classes: Gastropoda, Bivalvia and Cephalopoda.

A lake ecosystem includes biotic (living) plants, animals and micro-organisms, as well as abiotic (nonliving) physical and chemical interactions.

Kanab ambersnail subspecies of mollusc

The Kanab ambersnail, scientific name Oxyloma haydeni kanabense or Oxyloma kanabense, is a critically endangered subspecies or species of small, air-breathing land snail, a terrestrial pulmonate gastropod mollusc in the family Succineidae, the amber snails. The common name of the amber snails is based on the shell, which is translucent and when empty usually resembles the color of amber.

Succineidae family of molluscs

Succineidae are a family of small to medium-sized, air-breathing land snails, terrestrial pulmonate gastropod molluscs. They are commonly called amber snails because their thin fragile shells are translucent and amber-colored. They usually live in damp habitats such as marshes.

<i>Oxyloma elegans</i> species of mollusc

Oxyloma elegans is a species of small European land snail, a terrestrial pulmonate gastropod mollusk belonging to the family Succineidae, the amber snails.

The Page springsnail is a species of freshwater snail in the family Hydrobiidae, the mud snails. It is endemic to Arizona in the United States, where it is known only from the Upper Verde River drainage in Yavapai County.

Chittenango ovate amber snail species of mollusc

The Chittenango ovate amber snail, scientific name Novisuccinea chittenangoensis, is a species of small air-breathing land snail in the family Succineidae, the amber snails. This species was discovered in 1905, and was reported three years later as a subspecies of the oval ambersnail, Succinea ovalis. Several taxonomic reviews took place in the subsequent decades until the end of the 1980s, when the Chittenango ovate amber snail was finally judged to be a distinct species Novisuccinea chittenangoensis, based on chemical and morphological data.

Utah roundmouth snail species of mollusc

The Utah roundmouth snail, also known as the Utah valvata or desert valvata, scientific name Valvata utahensis, is a species of freshwater snail with a gill and an operculum, an aquatic gastropod mollusc in the family Valvatidae, the valve snails.

<i>Nymphoides peltata</i> species of plant

Nymphoides peltata is perennial, rooted aquatic plant with floating leaves of the family Menyanthaceae.

<i>Valvata piscinalis</i> species of mollusc

Valvata piscinalis, common name the European stream valvata or European valve snail, is a species of minute freshwater snail with gills and an operculum, an aquatic gastropod mollusk in the family Valvatidae, the valve snails. It is also known as Cincinna piscinalis.

<i>Physa fontinalis</i> species of mollusc

Physa fontinalis, common name the common bladder snail, is a species of air-breathing freshwater snail, an aquatic gastropod mollusk in the family Physidae. The shells of species in the genus Physa are left-handed or sinistral.

<i>Gillia altilis</i> species of mollusc

Gillia altilis, common name the Buffalo pebblesnail, is a species of freshwater snail, an aquatic gastropod mollusk with an operculum in the family Lithoglyphidae.

<i>Chara</i> (alga) genus of algae

Chara is a genus of charophyte green algae in the family Characeae. They are multicellular and superficially resemble land plants because of stem-like and leaf-like structures. They are found in fresh water, particularly in limestone areas throughout the northern temperate zone, where they grow submerged, attached to the muddy bottom. They prefer less oxygenated and hard water and are not found in waters where mosquito larvae are present. They are covered with calcium carbonate deposits and are commonly known as stoneworts. Cyanobacteria have been found growing as epiphytes on the surfaces of Chara, where they may be involved in fixing nitrogen, which is important to plant nutrition.

The respiratory system of gastropods varies greatly in form. These variations were once used as a basis for dividing the group into subclasses. The majority of marine gastropods breathe through a single gill, supplied with oxygen by a current of water through the mantle cavity. This current is U-shaped, so that it also flushes waste products away from the anus, which is located above the animal's head, and would otherwise cause a problem with fouling.

<i>Potamogeton coloratus</i> species of plant

Potamogeton coloratus, the fen pondweed, is an aquatic plant in the genus Potamogeton. It is found in shallow peaty calcareous lakes, ponds and ditches, commonly associated with lowland fens.

Quantula striata, also known as Dyakia striata, is a species of medium-sized, air-breathing, tropical land snail. It is a terrestrial, pulmonate, gastropod mollusk in the family Dyakiidae. This species appears to be unique among terrestrial gastropods in that it is bioluminescent: Its eggs glow in the dark, and juveniles and most adults give off flashes of green light. It is the only species in the genus Quantula.

<i>Clinostomum marginatum</i> species of worm

Clinostomum marginatum is a species of parasitic fluke. It is commonly called the "yellow grub". It is found in many freshwater fish in North America, and no fish so far is immune to this parasite. This type of fluke can also be found in the mouth of aquatic birds such as herons and egrets. They are commonly present in the esophagus of fish-eating birds and reptiles. Eggs of these trematodes are shed in the feces of aquatic birds and released into water. Aquatic birds become hosts of this parasite by ingesting infected freshwater fish. The metacercariae are found right beneath the skin or in the muscles of host fish.

References

This article incorporates CC-BY-3.0 text from the reference [1]

  1. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Arruda J. O. & Thomé J. W. (2011). "Biological aspects of Omalonyx convexus (Mollusca, Gastropoda, Succineidae) from the Rio Grande do Sul State, Brazil". Biotemas 24(4): 95-101. PDF, doi:10.5007/2175-7925.2011v24n4p95.