46 
AUSTRALIAN SPECIES OF RHYTIDOPONERA MAYR 
Rhytidoponera dixoni sp. nov. 
(PL IV, figs. 22-23.) 
Worker. — Length, 11 mm. 
Chocolate-brown, gaster black, apical segments of funiculi reddish-brown. 
Mandibles, scapes and tibiae finely striate longitudinally. Clypeus longi- 
tudinally rugose. Head rugose, longitudinal between frontal carinae, diverging 
outward behind, with a few large, very shallow punctures scattered between 
the rugae, interstices very finely reticulate. Pronotum transversely striate- 
rugose in front, irregularly punctate-rugose behind at sides, leaHng middle 
striate only, the punctures large, shallow and scattered. Mesonotum irregu- 
larly and somewhat coarsely punctate-rugose, as on part of pronotum. 
Epinotum coarse punctate-rugose behind, anterior fourth finely striate- 
reticulate with two or three obsolete punctures. Node very finely and densely 
reticulate in middle, punctate-rugose elsewhere. Gaster very finely striate 
transversely arched, femora densely reticulate with numerous small piligerous 
punctures. Coxae more coarsely reticulate. 
Hair yellow, long and erect on clypeus and apex of gaster, shorter but 
abundant on rest of body, suberect on antennae and legs. 
Head barely one-fifth longer than broad, sides feebly convex, occipital 
border with a concave depression in the middle, angles bluntly rounded, a sharp 
crest forms a slight sharp lateral projection. Mandibles with numerous very 
sharp denticles with five or six larger along each side. Clypeus broadly convex 
front and above. Frontal area very shallow behind. Frontal carinae as 
long as broad in front. Scapes extend beyond occipital border by fully one- 
third their length. Second segment of funiculi one-fifth longer than first 
and very slightly longer than third, apical not as long as the two preceding 
together. Eyes large and convex, i)laced just in front of posterior third of 
sides. Thorax twice as long as broad, pro-mesonotal suture strongly 
impressed. Pronotum one-fifth broader than long, sides and dorsum feebly 
convex. Mesonotum and epinotum strongly convex transversely. In profile 
pro-mesonotal suture strongly impressed, meso-epinotal suture indicated but 
not impressed. Pronotum one-fifth broader than long, sides and dorsum 
feebly convex. Mesonotum and epinotum strongly convex transversely. In 
profile pro-mesonotal suture strongly impressed, meso-epinotal suture indi- 
cated but not impressed. Pronotum convex, flattened in the middle. Meso- 
notum strongly convex, higher than rest of thorax. Epinotum straight, 
sloping downward behind, declivity at an obtuse angle, straight, as long as 
dorsum, into which it is strongly rounded. Node one-third broader than 
long, feebly convex behind, front and sides strongly convex. In profile stalk 
almost as long as top, top portion square, anterior and posterior faces straight 
and vertical, dorsum straight, anterior edge sharp, posterior edge rounded. 
Ventral spine long, slender and parallel, abruptly sharpened, twice as long as 
broad at base. Postpetiole one-fourth broader than long, sides and front 
strongly convex. First segment of gaster one-fourth broader than long, 
strongly convex behind. Constriction not strongly impressed. Legs robust. 
Male. — Length, 10- 5-11 mm. 
Blackish-brown. Mandibles and antennae reddish-brown. Wings hyaline, 
nervures brown. 
Mandibles longitudinally striate. Head finely reticulate-rugose, coarser 
behind, more punctate-rugose. Thorax irregularly and coarsely reticulate- 
rugose, scutellum more punctate-rugose. Node finely and densely reticulate 
with a few transverse rugae. Postpetiole shining, very delicately reticulate. 
Gaster shining, the reticulations almost obsolete. 
