Itea is a genus of about 10 species of shrubs and small trees.
 The leaves are alternate.
 Flowers are small, with 5 sepals and 5 petals, borne in racemes or spikes.
Gammaridae is a family of amphipods.
 In North America they are included among the folk taxonomic category of "scuds", and otherwise gammarids is usually used as a common name.
Sigmurethra is a taxonomic category of air-breathing land snails and slugs, terrestrial pulmonate gastropod molluscs.
 This is an informal group which includes the majority of land snails and slugs.
Aptera is an obsolete taxonomic category, which included the Apterygota along with various other wingless arthropods.
Cladorhiza inversa is a species of sponge in the taxonomic category of Demospongiae.
 The body of the sponge consists of a spicule and fibers and is water absorbent.
Cladorhiza segonzaci is a species of sponge in the taxonomic category of Demospongiae.
 The body of the sponge consists of a spicule and fibers and is water absorbent.
Helleborine is the common name for a number of species of orchid.
 It does not correspond to any currently used taxonomic category.
 Some of the plants called helleborines are classified in the genus "Epipactis", some in genus "Cephalanthera".
 A genus "Helleborine" was formerly recognised but has now been absorbed into the Grass pink genus "Calapogon".
Alocasia is a genus of broad-leaved rhizomatous or tuberous perennials from the family Araceae.
 There are 79 species native to tropical and subtropical Asia to Eastern Australia, and widely cultivated elsewhere.
Eogastropoda was a previously used taxonomic category of snails or gastropods, a subclass which was erected by Ponder and Lindberg in 1997.
 It was one of two great divisions (subclasses) of the class Gastropoda, the snails.
 The other subclass of gastropods was the Orthogastropoda.
Heterostropha was a previously used taxonomic category, an order of sea snails, within the superorder Heterobranchia.
 In the most current gastropod taxonomy, that of Bouchet & Rocroi, this taxon is no longer in use.

Question: To which taxonomic category do both Itea and Alocasia belong?
Answer: genus