(Figs. 42, 43, 73, 81)
HOLOTYPE WORKER. TL 5.60, HL 1.29, HW 1.48, FC 1.25, CS 1.38, SL 0.84, SI 1 57, SI 2 61, PML 1.12 PW 1.40, PMD 1.62, PMI 2 116, ML 1.33, PTLL 0.35, PTLH 0.63, PTDW 0.49, PPLL 0.36, PPLH 0.68, PPI 54, PPDW 0.55, PT / PP 89.
Mandible with four teeth. In full face view clypeus anteriorly with deep oblique concavity, markedly exceeding anterolateral frontal corners and distinctly carinulate. Head wider than long (CI 115), preoccipital margin moderately concave. Frontal carinae broad, only moderately narrower than head width (FI 118), evenly narrowing towards clypeus. With head in profile antennal scrobe reaching distinctly beyond middle of lateral side of head, transversely carinulae at rear, well defined posteriorly against remainder of head. Genae evenly carinate, ventrolateral sides of head and posterolateral lobes reticulate. Eyes medium sized (EL 0.33, REL 0.26, with 18 ommatidia in the longest row), situated at about middle of lateral sides of head, the dorsal ocular margin reaching the ventral scrobal margin. Dorsal surface of head coarsely rugoreticulate, interspaces glossy.
Promesonotal shield moderately wider than long (PMI 127), with a somewhat overall square impression, with mesonotal projections well developed, posterolateral spines curved and with distinct translucent fusion between projections. Propodeal spines not very long (PSL 0.45), narrow and acute, in dorsal view moderately arcuate.
Petiole in lateral view narrowly triangular, distinctly higher than long (PTI 56), with anterior face more or less straight, meeting convex rugose posterior face in a crest, ventral face sinuate. Postpetiole elongately nodiform with large antero-basal tooth.
First gastral tergite entirely microreticulate. Dorsal surfaces covered with shorter decumbent and longer erect and more stiff hairs.
Distinctly bicolored with the gaster and appendages yellow, the femora basally fuscous. Remainder of body piceous, except frontal carinae anterolaterally and translucent areas on promesonotal shield brighter.
WORKERS (n = 17). TL 4.95 - 6.05, HL 1.13 - 1.35, HW 1.28 - 1.55, FC 1.08 - 1.23, FI 113 - 123, CI 111 - 119, CS 1.20 - 1.43, SL 0.75 - 0.88, SI 1 56 - 60, SI 2 60 - 64, PML 0.93 - 1.13, PW 1.18 - 1.53, PMI 125 - 145, PMD 1.30 - 1.66, PMI 2 107 - 116, ML 1.10 - 1.38, PSL 0.39 - 0.48, PTLL 0.33 - 0.39, PTLH 0.58 - 0.68, PTI 55 - 61, PTDW 0.44 - 0.54, PPLL 0.33 - 0.38, PPLH 0.59 - 0.71, PPI 48 - 58, PPDW 0.45 - 0.76, PT / PP 66 - 97, EL 0.27 - 0.35, REL 0.22 - 0.26, with 15 - 18 ommatidia in the longest row.
ETYMOLOGY
The name refers to the narrow shape of the nodes.
ADDITIONAL MATERIAL EXAMINED
South Australia : Middleback Stn. HS , 20. - 25. vii. 1995 , ( McAllister ) ; 11.5 km SEWares Peak , 5. x. 1995 (coll. unknown) ; 8 km SEParalena Hill , Woltana Stn. , 26. - 31. viii. 1996 (coll. unknown) ; 16 km SSEMount Coffin , 9. - 12. xii. 1997 (coll. unknown) ; 14.7 km ESEMt. Coffin , Nth Moolooloo , 9. - 12. xii. 1997 (coll. unknown) ; 9 km SSEOakbank , 7. - 10. x. 1992 (coll. unknown) ; Murnpeowie , 17. xi. 1992 ( R. Brandle ) ; Murnpeowie , Mary's Pool , 17. xi. 1992 ( R. Brandle ) ; Mount Hopeless , 15. xi. 1994 ( R. Tynan ) ; Screech-Owl Creek , 27. iv. 1995 (coll. unknown) ; Willow Spring Stn. , 13.5 km NNEWillow Spring HS , 15. - 25. iii. 1995 (coll. unknown) ; 4.5 km SWWaraweena , 4. - 7. vii. 1999 (coll. unknown) ; 3 km SSWWaraweena , 1. - 10. x. 1999 (coll. unknown) ; Coober Pedy , 26. v. 1969 ( P. J. M. Greenslade ) ; Halbury , 10. x. 1984 ( B. B. Lowery ) ; Flinders Ranges , Oraparinna , 15. - 17. ix. 1971 ( P. J. M. Greenslade ) ; Moockra Tower , 6. x. 1974 & 13. x. 1980 ( P. J. M. Greenslade ) ; Tailem Bend , 21. vi. 1969 ( B. B. Lowery ) ; Hawker , 18. vi. 1972 ( B. B. Lowery ) . Victoria : Patho ( H. A. Petter ) ; NOuyen , ix. 1913 (coll. unknown) . New South Wales : 15 km NCoombah , 31. x. 1975 ( P. Ward ) ; Fowlers Gap Stn. , 110 km NBroken Hill , 11. x. 1980 ( S. R. Morton ) ; Hillston , 8. xii. 1965 ( B. B. Lowery ). (84 workers, 6 gynes, 1 male in ANIC , MVMA , NHMW , SAMA ) .
DISCUSSION
M. angustinodis is a very distinctive species, which is easily separated from others by the narrowly triangular petiole and the elongate large-toothed postpetiole. Widely distributed throughout south-eastern Australia.
