searchByClassification API fails to match well-defined searches

[mjwestgate]

I've been auditing galah-R issues filed by users, and found some that appear to be due to server-side behaviour. In this case, searches above the species level don't always match, even where that taxon is unambiguously present in the taxonomic backbone.

Example 1 (issue 200) is that searches for genus = "Equisetopsida" default to a higher-taxon match, despite this genus being visible in the BIE (here):
https://api.ala.org.au/namematching/api/searchByClassification?class=Equisetopsida&genus=Acanthocladium&rank=genus

Example 2 (issue 194) is that searches for genus = "Phyllotreta" return no match, despite being present in BIE (here):
https://api.ala.org.au/namematching/api/searchByClassification?genus=Phyllotreta&rank=genus