Nouns ending in -a (often Latin or scientific) add -e to form the plural.
Echidna is regular. It follows the -ae Addition rule.
Use plural verbs: "The echidnae are ready" (not "is ready").
Yes. The plural echidnae is standard across all English variants.
The word echidna follows the standard English pluralization rule. When forming the plural, echidna becomes echidnae. This follows the -ae Addition pattern, which is one of the most common plural rules in English.
Understanding why echidna becomes echidnae helps with spelling and pronunciation. Nouns ending in -a (often Latin or scientific) add -e to form the plural.
When using echidnae in writing, remember that it functions as a plural noun in sentences. It pairs with plural verbs and pronouns. For example: "The echidnae are ready" (not "is ready"). This subject-verb agreement is essential for grammatical correctness.