Article 30. Gender of genus-group names. The gender of a genus-group name is determined by the provisions of this Article.
30.1. Gender of names formed from Latin or Greek words. Subject to the exceptions specified in Article 30.1.4,
30.1.1. a genus-group name that is or ends in a Latin word takes the gender given for that word in standard Latin dictionaries; if it is a compound word formed from two or more components, the gender is given by the final component (in the case of a noun, the gender of that noun; in the case of any other component, such as a Latin suffix, the gender appropriate to that component);
Examples. Felis and Tuba, feminine; Salmo, Passer, Ursus and Turdus, masculine; Argonauta, masculine from the final noun nauta (a sailor), masculine; Lithodomus, feminine from the final noun domus (a home), feminine; Anser (a goose), masculine, as are names ending in it; Anseranas, feminine (a compound name of two nouns: Anser, masculine, but the final noun anas (a duck) is feminine); Anserina (Anser with the suffix -ina), feminine; Oculina, feminine (from the Latin masculine noun oculus and the feminine suffix -ina); Orca (from orca, a large-bellied pot), feminine; names formed from it by the addition of suffixes: Orcaella, feminine, and Orcinus, masculine.
30.1.2. a genus-group name that is or ends in a Greek word transliterated into Latin without other changes takes the gender given for that word in standard Greek dictionaries;
Examples. Greek nouns transliterated without change into Latin as the whole or part of a name: Ichthyornis, ending in -ornis (ornis), is masculine; Lepas (lepas) is feminine; Diadema (diadema) is neuter. Names ending in -caris (caris), -gaster (gaster), -lepis (lepis), or -opsis (opsis) are feminine; names ending in -ceras (keras), -nema (nema), -soma (soma), -stigma (stigma), or -stoma (stoma) are neuter.
30.1.3. a genus-group name that is a Greek word latinized with change of ending, or with a Latin or latinized suffix, takes the gender normally appropriate to the changed ending or the Latin suffix.
Examples. Names with the Latin gender ending -us, latinized from the Greek endings -os (masculine or feminine), -e (feminine), -a (neuter) or -on (neuter), are masculine: e.g. -cephalus (kephale), -cheilus and -chilus (cheilos), -crinus (krinon), -echinus (echinos), -gnathus (gnathos), -rhamphus (rhamphos), -rhynchus (rhynchos), -somus (soma), -stethus (stethos), and -stomus (stoma). Names ending in the Latin gender ending -a, latinized from the Greek ending -on are feminine, e.g. -metopa (metopon). Names derived from the Greek -keras (neuter) may have the ending -cerus (masculine) or -cera (feminine), although simple transliteration of the Greek ending as -ceras retains the neuter gender; Phorella (feminine) is derived from the Greek word phor (a robber, masculine) and the Latin diminutive suffix -ella (feminine); Scatella, feminine, is derived from skatos (neuter) and the Latin suffix -ella (feminine); Doridunculus (masculine) from Doris, Greek, the name of a sea godess (feminine), and -unculus a Latin suffix (masculine).
30.1.4. The following exceptions apply:
188.8.131.52. If the author states when establishing the name that it is not formed from, or is not treated as, a Latin or Greek word [Art. 26], the gender is determined as though the name is an arbitrary combination of letters (Article 30.2.2).
184.108.40.206. A genus-group name that is or ends in a word of common or variable gender (masculine or feminine) is to be treated as masculine unless its author, when establishing the name, stated that it is feminine or treated it as feminine in combination with an adjectival species-group name [Art. 31.2].
Examples. Bos is of common gender (meaning ox or cow); it and compound names ending in it (such as Ovibos), are treated as masculine. Compound Latin nouns ending in -cola (masculine or common gender in Latin): Agricola ("tiller of fields", masculine in Latin) is masculine, Sylvicola ("inhabitant of woods") and Monticola ("highlander") are treated as masculine. Petricola ("dweller among rocks", common gender in Latin) is feminine because it was originally treated as feminine by being combined with the specific names costata, striata and sulcata.
220.127.116.11. A compound genus-group name ending in -ops is to be treated as masculine, regardless of its derivation or of its treatment by its author.
18.104.22.168. A compound genus-group name ending in the suffix -ites, -oides, -ides, -odes, or -istes is to be treated as masculine unless its author, when establishing the name, stated that it had another gender or treated it as such by combining it with an adjectival species-group name in another gender form.
Examples. Hoplitoides and Harpides are masculine, but Aleptinoides (meaning "like Aleptina") is treated as feminine because that was the gender adopted by its original authors.
22.214.171.124. A genus-group name that is or ends in a Latin word of which the ending has been changed takes the gender appropriate to the new ending; if the ending is such as not to indicate a particular gender, the name is to be treated as masculine.
Example. Dendrocygna is feminine, although the second word in the combination is formed from cygnus (a swan), masculine.
30.2. Gender of names formed from words that are neither Latin nor Greek.
30.2.1. If a name reproduces exactly a noun having a gender in a modern European language (without having to be transliterated from a non-Latin alphabet into the Latin alphabet) it takes the gender of that noun.
Example. Pfrille, from the feminine German noun Pfrille (a minnow), is feminine.
30.2.2. Unless Article 30.2.1 applies, a name that is not formed from a Latin or Greek word takes the gender expressly specified by its author.
30.2.3. If no gender was specified, the name takes the gender indicated by its combination with one or more adjectival species-group names of the originally included nominal species [Art. 67.2.].
30.2.4. If no gender was specified or indicated, the name is to be treated as masculine, except that, if the name ends in -a the gender is feminine, and if it ends in -um, -on, or -u the gender is neuter.
Examples. Jackmahoneya (from Jack Mahoney) is masculine because its author specified it. Oldfieldthomasia (from Oldfield Thomas) and Dacelo (anagram of Alcedo) are feminine, being so treated by their authors. Abudefduf (from Arabic), Gekko (from Malay) and Milax (an anagram of Limax) are treated as masculine, because no gender was specified or indicated by their authors. Buchia (from von Buch), Cummingella (from Cumming), Zyzza (an arbitrary combination of letters) and Solubea (an anagram) are all treated as feminine, and the anagram Daption as neuter.
Recommendation 30A. Gender and derivation to be made explicit. Authors should expressly state the gender and derivation of a new genus-group name when establishing it.
Recommendation 30B. Gender to be made self-evident. So that the gender of new genus-group names is self-evident, authors, when forming new names based on words that are not Latin or Greek and stating their genders, are advised to choose genders for them appropriate to their endings.