silique vs siliqua

silique and siliqua both are nouns.

Word	Noun	Adjective	Verb	Adverb
silique	Yes	No	No	No
siliqua	Yes	No	No	No

As nouns, silique and siliqua are synonyms defined as:

silique and siliqua: narrow elongated seed capsule peculiar to the family Cruciferae

silique (noun)	siliqua (noun)
narrow elongated seed capsule peculiar to the family Cruciferae	narrow elongated seed capsule peculiar to the family Cruciferae