Key to Polyrhachis gravis species-group workers

This worker key is based on: Kohout, R.J. 2013. A review of the Polyrhachis gravis and micans species-groups of the subgenus Campomyrma Wheeler (Hymenoptera: Formicidae: Formicinae). Memoirs of the Queensland Museum, Nature 56, 92-117

You may also be interested in
 * Polyrhachis gravis species-group - diagnosis and biology
 * Campomyrma
 * Polyrhachis

1

 * Dorsum of petiole armed with single spine . . . . . 2


 * Dorsum of petiole armed with a pair of spines . . . . . 3

2
return to couplet #1
 * Pronotal humeri simply angular; eyes smaller, distinctly convex; dorsal petiolar spine long and acute . . . . . Polyrhachis pseudothrinax


 * Pronotal humeri produced into short, distinct teeth; eyes larger, only moderately convex; dorsal petiolar spine short and blunt 	. . . . . Polyrhachis unicornis

3
return to couplet #1
 * Petiolar node in profile distinctly swollen at base . . . . . Polyrhachis bispinosa


 * Petiolar node in profile slender, scale-like . . . . . 4

4
return to couplet #3
 * Pilosity generally long, hair-like, rather abundant . . . . . 5

5
return to couplet #4
 * Large species (HL 2.68); pilosity very long, abundant; lateral margins of propodeal dorsum barrel-shaped (VIC) . . . . . Polyrhachis captiva


 * Smaller species (HL < 2.50); pilosity shorter, more sparse, notably on dorsum of mesosoma; lateral margins of propodeal dorsum converging posteriorly (WA) . . . . . Polyrhachis capillata

6
return to couplet #4
 * Petiole high and slender in frontal view; dorsolateral margins steeply raised, strongly converging dorsally, forming single base for two slender dorsal spines; body black, somewhat semipolished, with appendages light orange (WA, Kimberley) . . . . . Polyrhachis palmerae


 * Petiole about as long as wide in frontal view; dorsolateral margins less steep and less strongly converging dorsally; bases of dorsal pair of spines more widely separated; body rather dull black, opaque, with appendages black or dark reddish-brown . . . . . 7

7
return to couplet #6
 * Dorsal petiolar spines tooth-like, distinctly shorter and stouter than lateral spines; bristle-like pubescence very sparse, virtually lacking from dorsum of mesosoma and petiole	. . . . . Polyrhachis curtospinosa


 * Dorsal petiolar spines slender, distinctly longer than lateral spines; bristle-like pubescence present on most body surfaces, including dorsum of mesosoma and petiole . . . . . 8

8
return to couplet #7
 * Anterior margin of first gastral tergite with strongly raised carina . . . . . 9


 * Anterior margin of first gastral tergite with only poorly indicated carina (WA) . . . . . Polyrhachis opacita

9
return to couplet #8
 * Antennal scapes longer (SI > 125); eyes more-or-less normal, moderately convex; pronotal humeri narrowly rounded with pronotal margins behind shallowly emarginated; greatest width of pronotal dorsum at middle of segment (NT, QLD) . . . . . Polyrhachis gravis


 * Antennal scapes shorter (SI 115) eyes distinctly smaller, strongly convex; pronotal humeri distinctly angular; greatest width of pronotal dorsum across humeri (WA) . . . . . Polyrhachis hespera