Genus Monomorium Descriptive Characteristics:Habitat: - Monomorphic- Pinon-Juniper under rocks - 12 segmented antennae - Nest - no mound, jut a hole in the ground - 3 segmented club - no spines or tubercles of any kind - M. pharaonis is yellow - Monomorium in Mexico are brown and shinny in El Paso, they are black, shinny and very tiny - Monomorium in Framington, NM some are brown and rough Behavior: - Not aggressive - Common in urban habitats - Common as house pests Note: Monomorium, spp are difficult to distinguish from Megalomyrmex, but the latter is usually in mature forest, and is bigger. In the field, Monomorium are very similar to small Solenonosis 3 segmented club Compiled by Hilda Taylor

Genus Myrmica Descriptive Characteristics:Habitat: - Body roughly sculpture- In high elevations - Pectinate tibial spurs- Forests in Mexico in Veracruz - Almost always black or dark brown- Found in the shade - Spines on the propodium - Metonotal constrictions Behavior -Slow, not aggressive -May sting Note: Need workers and also males to identify Myrmica Pectinate tibial spurs Metonotal constriction Spines

Genus Solenopsis Descriptive Characteristics:Habitat: -10-segmented antennae- Diverse and abundant in most habitats -2-segmented club- Many are cryptic in leaf litter and soil -Mesosoma lacking spines or tubercles- Some are conspicuous arboreal ants -smooth and shinny Behavior - Aggressive 2 segmented club

Descriptive Characteristics:Habitat: -11 – 12 antennal segments- Arid ecosystems found in arroyos -Sharp semicircular structures right before the insert of the antennae Behavior - Hide, non aggressive - May sting if disturbed Note: Tetramorium is very similar to Myrmica the latter does not have welts most of the time Genus Tetramorium Sharp semicircular carina

Genus Pheidole Descriptive Characteristics:Habitat: -Polymorphic small species- Extremely diverse habitats -Mandibles always triangular- Extremely common, one of the -Antennae always with 3 segmented club- most frequently encountered genera -Antennae usually 12 segmented, rarely 11 or 10- Nest – under wood, on ground, in -Propodeum usually with pair of teeth (may be reduced dead sticks, dead knots on tree trunks, to denticles, ridges or absent under bark flaps, under epiphytes from -Propodeal suture always present litter layer to high canopy Behavior: Not aggressive Note: Pheidole can easily be confused with Apheanogaster: look at 3-segmented club on Pheidole Apheanogaster does not have well defined clubs Soldier Worker Soldier

Genus Pogonomyrmex Descriptive Characteristics: Habitat: -Species in El Paso – bicolor ( P. rugosa)- Desert habitats -Long curved hairs on underside of head - May make nest on Dorymermex nests (psammophore)- May find P. barbatus in Mexico Behavior - Very aggressive Rugae Pointy Petiole Psammophore

Genus Pyramica Descriptive Characteristics:Habitat: -Labrum underneath the clypeus- Live in the soil - -Head very similar to Strumigenys- Found in litter = labral lobes well developed and prominent- Feed on Collembola Behavior - Slow, play dead Labrum

Genus Strumigenys Descriptive Characteristics:Habitat: -No labrum- Throughout tropical and subtropical -Hairs on head weird America, from the southern USA to -Not always have long mandibles Argentina - Nests mostly in soil and rotting wood - Most species are collembolan feeders Behavior: Non Aggressive some are polyphagous predators or occasionally feed on sugary substances - Workers prefer to feed on live sympyleonan Collembola; poduroid collembolans are not taken Note: Very similar to Pyramica and to Odontomachus

Genus Trachymyrmex Descriptive Characterists:Habitat: -11 segmented antennae- Found in Tropics and -Frontal carinae runs almost to the back in New Mexico of the head -Pronotum with sharp spines or bumps -Tubercles small not very big -Almost always red Behavior - Not aggressive Pronotum

Genus Wasmannia Descriptive Characteristics:Habitat: -11 segmented antennae - Found in tropics -2 segmented club- Found under rocks in Mexico -Petiole in the shape of rectangle- Common in soils -2 frontal carinae -2 scrabes where the scape originates Behavior - Will sting if disturbed, otherwise docile Note: Tetramorium also has longer carinae, but does not have 2 segmented club. Little native fire ants Scrobes 2 segmented club Rectangular