| Sagda alligans | |
|---|---|
|   | |
| Illustration of adult and juvenile shells of Sagda alligans | |
| Scientific classification   | |
| Domain: | Eukaryota | 
| Kingdom: | Animalia | 
| Phylum: | Mollusca | 
| Class: | Gastropoda | 
| Subclass: | Heterobranchia | 
| Order: | Stylommatophora | 
| Family: | Sagdidae | 
| Genus: | Sagda | 
| Species: | S. alligans | 
| Binomial name | |
| Sagda alligans (Reeve, 1851) | |
Sagda alligans is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Sagdidae.
The shell is imperforate, globosely conoidal, white, under a brownish-yellow epidermis. The incremental striae are regular, stronger on the spire than on the body whorl. The number of whorls is 8. The shell has a narrow, aperture with a deep-seated strong basal lamella. [1]
The adult shell diameter is 15–20 mm.

Achatinella byronii is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Achatinellidae. This species is endemic to Oahu, in the Hawaiian Islands.

Vertigo substriata is a species of minute air-breathing land snail, a terrestrial pulmonate gastropod mollusk or micromollusk in the family Vertiginidae, the whorl snails.

Sagda is a genus of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Sagdidae.
Microtralia ovulum is a species of minute air-breathing land snail, a terrestrial gastropod mollusk in the family Ellobiidae, the salt marsh snails.

Atlanta brunnea is a species of sea snail, a holoplanktonic marine gastropod mollusk in the family Atlantidae.

Atlanta echinogyra is a species of sea snail, a holoplanktonic marine gastropod mollusk in the family Atlantidae.

Clanculus stigmatarius is a species of sea snail, a marine gastropod mollusk in the family Trochidae, the top snails.
Sinezona beddomei is a species of minute sea snail, a marine gastropod mollusk or micromollusk in the family Scissurellidae, the little slit snails.
Sukashitrochus atkinsoni is a species of minute sea snail, a marine gastropod mollusk or micromollusk in the family Scissurellidae, the little slit snails.
Sukashitrochus carinatus is a species of minute sea snail, a marine gastropod mollusk or micromollusk in the family Scissurellidae, the little slit snails.
Awateria retiolata is an extinct species of sea snail, a marine gastropod mollusk in the family Borsoniidae.

Maoritomella subalbula is an extinct species of sea snail, a marine gastropod mollusk in the family Borsoniidae.

Zemacies torticostata is an extinct species of sea snail, a marine gastropod mollusk in the family Borsoniidae.

Buccinanops cochlidium, common name the gradated bullia, is a species of sea snail, a marine gastropod mollusk in the family Nassariidae, the Nassa mud snails or dog whelks.

Antiguraleus infandus is a species of sea snail, a marine gastropod mollusk in the family Mangeliidae.

Antiguraleus murrheus is a species of sea snail, a marine gastropod mollusk in the family Mangeliidae.
Antiguraleus abnormis is an extinct species of sea snail, a marine gastropod mollusk in the family Mangeliidae.

Comitas latiaxialis is an extinct species of sea snail, a marine gastropod mollusc in the family Pseudomelatomidae.
Zetela praetextilis is an extinct species of sea snail, a marine gastropod mollusk, in the family Solariellidae. This species occurs in New Zealand.
Parasyrinx alta is an extinct species of sea snail, a marine gastropod mollusk unassigned in the superfamily Conoidea.