Tetramorium species groups

It is convenient to organize species by region and species groups. This approach has been followed by most of the more informative taxonomic treatments of Tetramorium. The contents of this page are an attempt to organize information from various papers, as detailed in the list of references at the bottom of the page. There still remains much work to be done, with future taxonomy both adding to and potentially changing previous groups, arrangements and identification keys. With this in mind this page and other Tetramorium species groups webpages are provisional - and are not meant to represent a complete or definitive overview of this diverse and widely distributed genus.

Afrotropical region Tetramorium
More than half of the ~ 450 species occur in this region.

Tetramorium simillimum species group
This group includes species from two regions.
 * Tetramorium altivagans
 * Tetramorium anxium
 * Tetramorium argenteopilosum
 * Tetramorium arnoldi
 * Tetramorium berbiculum
 * Tetramorium bevisi
 * Tetramorium bothae
 * Tetramorium buthrum
 * Tetramorium caldarium
 * Tetramorium delagoense
 * Tetramorium ghindanum
 * Tetramorium krynitum
 * Tetramorium luteolum
 * Tetramorium mossamedense
 * Tetramorium nefassitense
 * Tetramorium nigrum
 * Tetramorium oculatum
 * Tetramorium pauper
 * Tetramorium poweri
 * Tetramorium pusillum
 * Tetramorium rhetidum
 * Tetramorium simillimum

Tetramorium tortuosum species group
This is a large group overall but it is not diverse in the Afrotropical region. The three species from this group in this region are grouped together in the:

Tetramorium capillosum species complex
Key to the Tetramorium capillosum species complex


 * Tetramorium capillosum
 * Tetramorium hecate
 * Tetramorium tabarum

This species complex is endemic to this region.

Tetramorium weitzeckeri species group
Key to the Afrotropical weitzeckeri-group species.

Indo-Australian
Key to the Australian Tetramorium

Malagasy Tetramorium
The species of the Malagasy region can be placed into the following species groups.

Key to Malagasy Tetramorium species groups

Tetramorium bicarinatum species group
A number of species in this group are tramp species. There are three members of the group in the Malagasy region.


 * ''Tetramorium bicarinatum
 * ''Tetramorium insolens
 * ''Tetramorium pacificum

Tetramorium bessonii species group
An endemic Malagasy group.

Key to Tetramorium bessonii-group workers


 * Tetramorium artemis
 * Tetramorium bessonii
 * Tetramorium malagasy
 * Tetramorium orientale
 * Tetramorium ryanphelanae
 * Tetramorium wardi

Tetramorium bonibony species group
Endemic to the Malagasy region, the group is comprised of 8 species.

Key to Tetramorium bonibony-group species


 * Tetramorium bonibony
 * Tetramorium kali
 * Tetramorium nosybe
 * Tetramorium olana
 * Tetramorium popell
 * Tetramorium sada
 * Tetramorium trafo
 * Tetramorium vony

Tetramorium dysalum species group
All appear to be endemic to the Malagasy region.

Key to Tetramorium dysalum-group species


 * Tetramorium ambatovy
 * Tetramorium dysalum
 * Tetramorium mackae
 * Tetramorium mallenseana
 * Tetramorium orc
 * Tetramorium robitika
 * Tetramorium sargina
 * Tetramorium steinheili
 * Tetramorium vohitra
 * Tetramorium yammer

Tetramorium kelleri species group
Endemic to Madagascar, there are two species in this group.


 * Tetramorium ankarana
 * Tetramorium kelleri

Tetramorium marginatum species group
An endemic Madagascar group comprised of 6 species.

Key to Tetramorium marginatum-group species


 * Tetramorium hector
 * Tetramorium marginatum
 * Tetramorium norvigi
 * Tetramorium shamshir
 * Tetramorium silvicola
 * Tetramorium valky

Tetramorium obesum species group
The single member of this group that occurs in the Malagasy species is a well known, widespread tramp species.


 * ''Tetramorium lanuginosum

Tetramorium plesiarum species group
A provisional group name for Tetramorium plesiarum and numerous allied, undescribed forms that do not fit well within T. ranarum species group.

Tetramorium ranarum species group
An endemic species group only found in the Malagasy region that holds numerous valid and more than 25 tentatively undescribed species.


 * Tetramorium coillum
 * Tetramorium degener
 * Tetramorium ibycterum
 * Tetramorium quasirum
 * Tetramorium ranarum
 * Tetramorium zenatum

Tetramorium schaufussii species group
An endemic Madagascar group that includes 6 described species and possibly dozens more that are undescribed.

Tetramorium sericeiventre species group
This group is present in the Malagasy region in the form of two species, one of which is shared with the Afrotropical and Southern Palaearctic regions, while the other represents a new species (T. mahafaly) endemic to Madagascar.


 * ''Tetramorium mahafaly
 * ''Tetramorium sericeiventre

Tetramorium severini species group
This species group contains a single species, T. severini, that is one of the most conspicuous Tetramorium species found in Madagascar.


 * Tetramorium severini

Tetramorium simillimum species group
This group includes species from other regions. Within the Malagasy region there are 5 described species and potentially 2 new species.


 * Tetramorium anodontion
 * Tetramorium caldarium
 * Tetramorium delagoense
 * Tetramorium simillimum
 * Tetramorium scytalum

Tetramorium tsingy species group
Endemic to a comparatively small area in Western Madagascar


 * Tetramorium tsingy
 * Tetramorium tyrion

Tetramorium tortuosum species group
This group is widespread and present in most zoogeographic regions except the Palaearctic. Nevertheless, the highest species richness can be found in the Oriental and Indo-Australian regions while the Afrotropics and the New World are relatively species-poor. In the Malagasy region it is represented by about 20 species.

Key to Malagasy Tetramorium tortuosum-group workers

Tetramorium andrei species complex

 * Tetramorium ala
 * Tetramorium andohahela
 * Tetramorium andrei
 * Tetramorium electrum
 * Tetramorium elf
 * Tetramorium isectum
 * Tetramorium isoelectrum
 * Tetramorium nify
 * Tetramorium voasary

Tetramorium jedi species complex

 * Tetramorium avaratra
 * Tetramorium jedi
 * Tetramorium pleganon

Tetramorium noeli species complex

 * Tetramorium aherni
 * Tetramorium ambanizana
 * Tetramorium noeli
 * Tetramorium singletonae

Tetramorium smaug species complex

 * Tetramorium adamsi
 * Tetramorium marojejy
 * Tetramorium latreillei
 * Tetramorium nazgul
 * Tetramorium sabatra
 * Tetramorium smaug

Tetramorium tosii species group
An apparently endemic group from the Malagasy region.


 * ''Tetramorium tantillum
 * ''Tetramorium tosii

Tetramorium weitzeckeri species group
This group is diverse in the Afrotropical region: Afrotropical Tetramorium weitzeckeri species group. The sole representive in the Malagasy region also occurs in the Afrotropics.

Tetramorium humbloti

New World Tetramorium
Relatively depauperate with just 13 species.

Key to US species

Palaearctic Tetramorium
See Steiner et al., 2005; Schlick-Steiner et al., 2006a; Csösz et al., 2007; Csösz & Schulz, 2010; Steiner et al., 2010.