Grammar

Helix:

The rule is that genus starts with a capital and specific epithet doesn’t, e.g. Homo sapiens. Both are italicised.

Anything else - kingdom, phylum, class, order, family and categories in between — are capitalised when used as proper nouns but aren’t italicised.

Old Big Box:

Re the capitalisation of non-scientific names referring to groups of animals, is governed by more than one common usage.

Names such as insect, centipede, millipede included within a sentence are usually begun with a lower case letter.

Insects, or the other non-scientifically named organisms, beginning a sentence will have an upper case letter.

Common names of flora and fauna like “Black-spotted Centipede” is also started with an upper case letter.

Binomial nomenclature - Wikipedia