A review of the genus Mystrium (Hymenoptera: Formicidae) in the Indo-Australian region. Author Bihn, J. H. Author Verhaagh, M. text Zootaxa 2007 1642 1 12 http://hdl.handle.net/10199/15412 journal article 21332 EE70683C-1EF6-4AE4-B8FF-0C6CE2B68C52 Tabular key to Indo-Australian species [[ of the genus Mystrium ]] based on the worker

M. camillae	M. leonie	M. maren
Mandibles	Relatively short; the distal 1/3 slightly incurved in dorsal view; the apex of each mandible distinctly expanded and rounded in lateral view, often with a more or less triangular and caudally directed tip at the inner side; dorsal face of each mandible with a carina covering almost its entire length.	Long and slender; basal 2/3 straight, distal 1/3 incurved; the apex of each mandible only slightly expanded and subtruncate in lateral view; distal 3/4 of the dorsal face of each mandible with a longitudinal carina.	Very long and slender; the outer and inner margins of each mandible in dorsal view parallel and distinctly sinuate; the apex of each mandible only slightly expanded and subtruncate in lateral view; distal 2/3 of the dorsal face of each mandible with a longitudinal carina.
Maxillary palpi	4-segmented; the 2nd segment shorter than the 1st; 1st segment very broad (fig. 10).	3-segmented; the 1st segment only slightly broader than the 2nd segment and cylindrical (fig. 11).	4-segmented; the 2nd segment longer than the 1st; the 1st segment much broader than the 2nd and cone-shaped (fig. 12).
Clypeal teeth	6-7 teeth arranged in 2 groups along the clypeal margin; the 2 groups in most cases separated by a toothless, median gap (fig. 1).	8 teeth evenly spaced along clypeal margin, without a toothless median gap (fig. 4).	9 teeth evenly spaced along clypeal margin, without a toothless median gap (fig. 7).
Labrum	Weakly developed, irregular rugoreticulum covers entire outer (ventral) face of labrum (fig. 13).	Irregular rugoreticulum on distal half of outer (ventral) face of labrum (fig. 14).	Bilateral-symmetric rugoreticulum on distal half of outer (ventral) face of labrum (fig. 15)
Head	With a short, triangular spine on each side.	With a long and curved spine on each side.	With a long and curved spine on each side.
Antennae	Length of each segment III-VIII equal to or slightly longer than its maximum width; segment III shorter than twice its width.	Each segment II-VIII longer than its maximum width; segment III at least twice as long as wide.	Each segment II-VIII longer than its maximum width; segment III at least twice as long as wide.
Propodeal spiracle	Directed caudad.	Directed laterocaudad.	Directed laterad.
Sculpture on posterior face of propodeum	Regular, reticulate microsculpture.	Reticulate microsculpture overlaid by rough rugoreticulum.	Regular, reticulate microsculpture.
Petiolar node	Width of node in dorsal view equal to or less than twice its length.	Node in dorsal view more than twice as broad as long.	Node in dorsal view more than twice as broad as long.