Q: Should the term "Perciformes" be italicized in scientific writing?

Detailed Question -

Is “Perciformes” should be written in italic or otherwise? This word is found in the English texts about the veterinary medicine “fosfomycin” just like “pseudotuberculosis of Perciformes...” I am not sure even though I keep referring to ICZN.

1 Answer to this question

"Perciformes" is an order or superorder of the largest group of fish in the world. An order, in biology, refers to a rank or level in the taxonomic classification system. From the most inclusive to the most exclusive, this taxonomy has eight levels:  

  1. Domain
  2. Kingdom 
  3. Phylum 
  4. Class 
  5. Order 
  6. Family 
  7. Genus 
  8. Species Identifier 

"Order" comes between class and family in this hierarchy. For instance, Class Mammalia includes Order Chiroptera (bats), Order Primates (primates), Order Carnivora (meat-eating mammals), Order Cetacea (whales and purpoises), Order Insectivora (insect-eaters), etc.

Generally speaking, in scientific writing, the names of the following are capitalized: kingdom, phylum, subphylum, class, subclass, superorder, order, suborder, superfamily, family, subfamily, tribe, genus, subgenus. On the other hand, the names of superspecies, species, and subspecies are not capitalized. Therefore, going by this convention, the word "Perciformes" should be capitalized.

However, there is no clear mention of whether the term should be italicized. Generally, only scientific names of species are italicized. I checked several biology research papers that used the term "Perciformes" and did not find it italicized anywhere. Therefore, the general convention seems to be that the word is capitalized but not italicized.

Related reading:

Capitalizing eponyms or names of diseases, syndromes, and objects in medical writing