Phasmid Study Group

By Judith Marshall

[taken from original article published in PSG Newsletter 97, pp.17-18, 2003]

For both people and pets, including stick-insects, we have males and females, and usually only refer to inanimate objects as ‘it', or of neuter gender - neither male nor female. For the scientific names of animals and plants we use words which may be masculine (m.), feminine (f.) or neuter (n.).

Each animal or plant bears a couplet of scientific names, the generic name or genus, always cited with a capital letter, and which may be thought of as the equivalent of a person's surname; and the specific name or species, which may be thought of as a given name (though always cited in lower case). There may beseveral species of different names included in each genus, showing their close relationship to each other.

Scientific names area often of Greek (G.) or Latin (L.) origin, or if from any other language are usually Latinised (= given Latin endings).

For many generic names the gender of the name is made clear by the ending; names ending in -us are usually masculine e.g. Carausius, names ending in -a are usually feminine, e.g. Acrophylla, and names ending -um are usually neuter, e.g. Baculum.

If a generic name is formed from two (or more) words, as in Acro- (G. n.) and -phylla (G.f.), it is always the gender of the last word which is taken for the whole name, so Acrophylla is feminine.

One of the (many!) rules of the International Code of Zoological Nomenclature (often just referred to as ‘the Code') is that if the specific name is an adjective, i.e. a descriptive word, it must agree in gender with that of the generic name. Thus the name meaning ‘spiny' may be spelt as spinosus (m.), spinosa (f.) or spinosum (n.), depending on the gender of the generic name: e.g. Carausius spinosus (both masculine).

A minor complication in this ‘agreement' process is that sometimes generic names ending in -a may not be feminine, as in the cricket genus Acheta which is actually masculine (meaning a male cicada!) - hence Acheta domesticus (Linnaeus) is the correct scientific name of the house-cricket. Also the stick-insect genus Bactrododema is neuter, being derived from bactron, a stick or rod (G.) and demas, the living body (G.), both of neuter gender, hence Bactrododema
tiaratum (Stal). Here the adjectival name tiaratum is derived from the noun tiara (G. f.), and is similarly used in Extatosoma tiaratum, with -soma, body (G. n.) so the name translates literally as ‘the ecstatic-bodied tiara'!

With the full scientific name the surname of the author (the original describer) of the species, follows the species name, e.g. Phyllium bioculatum Gray.

A species may be moved from one genus to another, and then the author's name is placed in parentheses (round brackets) to show a change has been made - as in Acheta domesticus
(Linnaeus). If the specific name is adjectival, then by the rules of the Code, the adjectival ending must agree in gender with that of the genus; e.g. Sceptrophasma hispidula (Wood-Mason) was originally described as Bacillus hispidulus Wood-Mason.

Specific names which are not adjectival do not changegender, e.g. Lonchodes harmani, (named after Allan Harman), and Hoploclonia abercrombiei (named after Ian Abercrombie); the -i ending is masculine; though if either Allan or Ian were women the names would have be L.harmanae and H. abercrombieae as the -ae ending is feminine.

Specific names which are nouns do not change in gender to agree with the genus, e.g. Malacomorpha cyllarus was described as Necroscia cyllarus, and both Necroscia and Malacomorpha are feminine, but the name ‘cyllarus' is the generic name of a bug, which presumably Westwood considered the stick-insect resembled.

This may all seem strange and unnecessary, especially when it is difficult to work out the original meaning of the word and hence its gender, so it is very helpful when an author explains the etymology of each name - how and why it has been derived.

One of the rules of the Code is that all names must be different, i.e. within each genus all species must have a different name - so if by chance two different species have been given an identical name the younger name - or ‘junior homonym' must be replaced. In human terms, having two brothers with the same surname and both called ‘John' would be very confusing! There are also similar masculine/feminine rules for the names of people, e.g. as members of the PSG we have Frances (Lazenby) female and Francis (Seow-Chen) male.

There is a similar Code and set of rules for the Plant Kingdom, and an identical name may be used for both an animal and a plant, e.g. Bacteria is both a genus of rod-shaped stick-insects, and is also the name of a group of rod-shaped microscopic members of the Plant Kingdom.

Of course we don't always get it right the first time, and often we have discussions about interpretation, e.g. ‘just what exactly did Westwood mean in 1859, and could he have got it wrong to start with?' - but that's all part of the fun!