''Diloma aethiops'', whose common names include scorched monodont, spotted black topshell, and in the

Māori language Māori (; endonym: 'the Māori language', commonly shortened to ) is an Eastern Polynesian languages, Eastern Polynesian language and the language of the Māori people, the indigenous population of mainland New Zealand. The southernmost membe ...

pūpū, pūpū-mai, or māihi is a

species 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. It is the basic unit of Taxonomy (biology), ...

of small

sea snail Sea snails are slow-moving marine (ocean), marine gastropod Mollusca, molluscs, usually with visible external shells, such as whelk or abalone. They share the Taxonomic classification, taxonomic class Gastropoda with slugs, which are distinguishe ...

, a marine

gastropod Gastropods (), commonly known as slugs and snails, belong to a large Taxonomy (biology), taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, freshwater, and fro ...

mollusc Mollusca is a phylum of protostome, protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant taxon, extant species of molluscs are recognized, making it the second-largest animal phylum ...

in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Trochidae The Trochidae, common name top-snails or top-shells, are a family of various sized sea snails, marine gastropod molluscs in the subclass Vetigastropoda. This family is commonly known as the top-snails because in many species the shell resembles ...

, subfamily

Monodontinae The narwhal (''Monodon monoceros'') is a species of toothed whale native to the Arctic. It is the only member of the genus ''Monodon'' and one of two living representatives of the family Monodontidae. The narwhal is a stocky cetacean with a ...

.Bouchet, P. (2013). Diloma aethiops (Gmelin, 1791). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=546856 on 2014-03-17

Description

The size of the shell varies between 15 mm and 30 mm. The thick, solid, imperforate shell has a depressed conical shape. It is blackish, dotted upon the ribs with yellow or white. The conic

spire A spire is a tall, slender, pointed structure on top of a roof of a building or tower, especially at the summit of church steeples. A spire may have a square, circular, or polygonal plan, with a roughly conical or pyramidal shape. Spire ...

is more or less depressed with an acute

apex The apex is the highest point of something. The word may also refer to: Arts and media Fictional entities * Apex (comics) A-Bomb Abomination Absorbing Man Abraxas Abyss Abyss is the name of two characters appearing in Ameri ...

. The five

whorl A whorl ( or ) is an individual circle, oval, volution or equivalent in a whorled pattern, which consists of a spiral or multiple concentric objects (including circles, ovals and arcs). In nature File:Photograph and axial plane floral diagra ...

s are spirally strongly ridged. The ridges are nodulous and number three on the penultimate whorl. The interstices are spirally striate. The

body whorl The body whorl is part of the morphology (biology), morphology of the gastropod shell, 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 ...

is depressed, angulate at the periphery, and concentrically lirate below. The lirae are coarsely granulose, about 5 in number. The

aperture In optics, the aperture of an optical system (including a system consisting of a single lens) is the hole or opening that primarily limits light propagated through the system. More specifically, the entrance pupil as the front side image o ...

is very oblique. The outer

lip The lips are a horizontal pair of soft appendages attached to the jaws and are the most visible part of the mouth of many animals, including humans. Mammal lips are soft, movable and serve to facilitate the ingestion of food (e.g. sucklin ...

is edged with blackish, then nacreous, and lined with opaque white, the thickening slightly notched at the place of the periphery. The oblique

columella Lucius Junius Moderatus Columella (, Arabic: ) was a prominent Roman writer on agriculture in the Roman Empire. His in twelve volumes has been completely preserved and forms an important source on Roman agriculture and ancient Roman cuisin ...

is nearly straight, flat, opaque white and backed by nacreous. Animal: The foot is yellow below, with a brown stripe round the contour, black on the sides, with touches of yellowish-white behind; filaments greenish; mouth yellowish.Hutton F.W. (1880) Manual of the New Zealand Mollusca, Dominion Museum (N.Z.)
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Distribution and Habitat

This species is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

. It is common to abundant in rocky

intertidal The intertidal zone or foreshore is the area above water level at low tide and underwater at high tide; in other words, it is the part of the littoral zone within the tidal range. This area can include several types of habitats with various sp ...

areas, where it is the only trochid found on open rock surfaces, in sheltered areas and semi-exposed coasts. In harbours or estuaries it often occurs with ''D. subrostrata'' on hard packed mud among empty

bivalve Bivalvia () or bivalves, in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class (biology), class of aquatic animal, aquatic molluscs (marine and freshwater) that have laterally compressed soft bodies enclosed b ...

shells.

References

* Miller M & Batt G, ''Reef and Beach Life of New Zealand'', William Collins (New Zealand) Ltd, Auckland, New Zealand 1973 * Powell A W B, ''New Zealand Mollusca'', William Collins Publishers Ltd, Auckland, New Zealand 1979 * Willan, R.C.; Marshall, B.A.; Climo, F.M.; Cernohorsky, W.O. 1980: ''Rectification of nomenclature for Melagraphia aethiops (Gmelin) and Diloma bicanaliculata (Dunker) (Mollusca: Trochidae).'' New Zealand Journal of Marine and Freshwater Research 14: 413-415 * Donald K.M., Kennedy M. & Spencer H.G. (2005) ''The phylogeny and taxonomy of austral monodontine topshells (Mollusca: Gastropoda: Trochidae), inferred from DNA sequences''. Molecular Phylogenetics and Evolution 37: 474–483.

External links

* {{Taxonbar, from=Q5277008 aethiops Gastropods of New Zealand Endemic fauna of New Zealand Gastropods described in 1791 Taxa named by Johann Friedrich Gmelin Endemic molluscs of New Zealand