From a Writing Tip I wrote recently for my team.
NOTE: The advice in this post refers to Australian authorities — check your country’s authorities for advice on whether common names of species are capitalized.
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Paul asked: Should we use capital letters [caps] when referring to the common name of an animal? i.e. scientific name – Lates calcarifer; common name – ‘Barramundi’ or ‘barramundi’? I know you have previously advised to use initial caps but is this a nomenclature standard across all taxa (animals and fish)?

Photo of a Barramundi from: http://www.ntfishing.com.au/881/barramundi-run-off-fishing-shady-camp/img_0121/ (Barramundi tastes REAL good too!)
My response:
When you’re referring to a specific common name, yes, you use initial caps for each word (e.g. Banded Lizardfish, Barramundi [one word common name only], Flatback Turtle). EXCEPTION: Only cap the first word of a compound/hyphenated word and keep the second word in lowercase (e.g. White-winged Fairy-wren, Tail-light Lanternfish, Northern Freetail-bat). However, if you’re referring to a generic group, you use lower case (e.g. lizardfish, turtles, bats, mangroves). This general rule applies to all taxa – flora and fauna.
This guidance is documented in [our] Editorial Guide, and follows the conventions used by the Western Australian Museum.
For examples of the Western Australian Museum’s use of capitals (and the use of caps for common names by other Australian institutions) see:
- http://museum.wa.gov.au/explore/blogs/aquatic-zoology/whats-name
- http://museum.wa.gov.au/explore/galleries/wildlife-houtman-abrolhos
- http://biocache.ala.org.au/occurrence/search?q=collection_uid:co123#tab_recordsView
NOTE: If you’re writing about fish species, there’s a definitive guide to naming Australian fish (including complete species lists) here: http://www.cmar.csiro.au/e-print/open/yearsleygk_2006a.pdf (see #9 on page 7, and the list of all fish species in Appendix A). Unlike mammals, birds etc. the fish people at the various institutions in Australia got together and decided not to use hyphenated words, where possible, so you end up with common names such as ‘Manyspot Flyingfish’. The introductory pages prior to the list of species makes for interesting reading on how they arrived at these naming conventions.
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See also: https://cybertext.wordpress.com/2012/01/26/to-cap-or-not-to-cap-that-is-the-question/
[Links last checked February 2014]