Key to Myrmica of South and South East Asia

This worker key is based on: Radchenko, A.G. & Elmes, G.W. 2010. Myrmica ants of the Old World. Fauna Mundi 3: 1-789.

-M. mixta is known only from the holotype queen collected in Sichuan Prov. of China; it has a very unusual combination of morphological features, and generally seems to be intermediate between the ritae- and inezae species-groups. Its quite coarse body sculpture, very long propodeal spines and fig-shaped postpetiole are all features of the ritae-graup. On the other hand, the not-notched anterior clypeal margin, relatively short scape, not pointed propodeal lobes, not well marked and not sharp upper latero-ventral corners of the head and another shape of petiole contradict with the characters of the ritae-group species.

1

 * Scape strongly angularly curved at the base, with small vertical lobe. - China: Sichuan Prov. . . . . . Myrmica sinoschencki


 * Scape gradually curved at the base, without any trace of ridge or lobe . . . . . 2

2
return to couplet #1
 * Alitrunk dorsum partly with transversal rugosity . . . . . 3


 * Alitrunk dorsum with various sculpture, but never with transversal rugosity . . . . . 13

3
return to couplet #2
 * Lateral and occipital margins of head with long numerous suberect to erect hairs . . . . . 4


 * Lateral margins of head either with no pilosity or with short decumbent hairs; if any long erect to suberect hairs present, they are restricted to the occipital margin and genae . . . . . 8

4
return to couplet #3
 * Head slightly longer than broad, CI < 1.15, subsquare, with distinctly marked occipital corners. - China: Yunnan Prov. . . . . . Myrmica pleiorhytida


 * Head distinctly elongate, CI > 1.20, suboval, with barely marked occipital corners . . . . . 5

5
return to couplet #4
 * Mesonotal andpropodeal dorsum with relatively coarse transversal rugosity, number of rugae on this area ≤ 20 . . . . . 6


 * Mesonotal and propodeal dorsum with finer transversal rugosity, number of rugae on this area ≥ 25 . . . . . 7

6
return to couplet #5
 * Petiole low, PI1 1.68, its node with elongate flattened dorsum. Body colour reddish-brown. - China: Shaanxi Prov. . . . . . Myrmica weii


 * Petiole higher, PI1 < 1.55, its node with a short, slightly convex, gradually sloping posteriorly dorsal surface. Body colour blackish-brown. - China: Shaanxi Prov. . . . . . Myrmica multiplex

7
return to couplet #5
 * Frontal carinae merge with the rugae that extend back to the posterior head margin, do not curve outwards and do not merge with the rugae that surround antennal sockets. Frons wider, FI 0.44-0.45. Surface of head dorsum between rugae appears shiny, only finely superficially micropunctated. - China: Yunnan Prov. . . . . . Myrmica yunnanensis


 * Frontal carinae curved outwards to merge with the rugae that surround antennal sockets; frons narrower, FI 0.39. Surface of the head dorsum between rugae coarsely and densely punctated, appears dull - China: Yunnan Prov. . . . . . Myrmica heterorhytida

8
return to couplet #3
 * Basal third of first gastral tergite densely punctated and longitudinally ruguloso-striated; this sculpture gradually reducing posteriorly, the rest of surface of the tergite with well visible superficial hexagonal microsculpture (seen under magnification> 50x). - China: Sichuan Prov. . . . . . Myrmica sculptiventris


 * Whole surface of first gastral tergite smooth (seen under magnification > 50x) . . . . . 9

9
return to couplet #8
 * Propodeal spines long, ESLI > 0.45, massive, strongly widened at the base and often curved down on their distal third. - China: Shaanxi Prov. . . . . . Myrmica taibaensis


 * Propodeal spines shorter, ESLI < 0.40, slender and straight . . . . . 10

10
return to couplet #9
 * Head dorsum posterior to the eyes with reticulation, rest of head dorsum with longitudinal rugosity. - China: Yunnan Prov. . . . . . Myrmica polyglypta


 * Head dorsum posterior to the eyes with longitudinal rugosity; reticulation, if present, restricted to temples and/or posterior part of occiput . . . . . 11

11
return to couplet #10
 * Lateral margins of head posterior to the eyes with abundant short decumbent hairs. Frontal carinae curve outwards to merge with the rugae that surround the antennal sockets. - China: Shaanxi Prov. . . . . . Myrmica schulzi


 * Lateral margins of head posterior to the eyes without short decumbent hairs. Frontal carinae merge with the rugae that extend back to the posterior head margin, do not curve outwards and do not merge with the rugae that surround antennal sockets . . . . . 12

12
return to couplet #11
 * Rugosity on the head dorsum partly reduced. Frons (level with the eyes) having < 15 fine, slightly sinuous longitudinal rugae, with only some of them extending unbroken to the occipital margin; surface between rugae densely and quite coarsely punctated, appearing dull. Propodeal dorsum with transversal rugosity. Scape longer than head width. - China: Shaanxi Prov. . . . . . Myrmica phalacra


 * Rugosity on the head dorsum not reduced. Frons (level with the eyes) having > 20 longitudinal rugae that extend unbroken to the occipital margin; surface between rugae very finely superficially punctated but appearing more or less shiny. Propodeal dorsum with short, slightly sinuous longitudinal rugae. Scape shorter than head width. - China: Sichuan Prov. . . . . . Myrmica hlavaci

13
return to couplet #2
 * Anterior clypeal margin not-notched medially; frontal carinae curved outwards to merge with the rugae that surround antennal sockets. Propodeal lobes rounded apically; body not slender, scape, propodeal spines and petiole shorter (SI1 < 0.90, ESLI ≤ 0.40, PI1 ≤ 1.55) . . . . . 14


 * Anterior clypeal margin distinctly notched medially; frontal carinae merging with rugae that extend to the occipital margin, they do not curve outwards and do not merge with rugae that surround antennal sockets. Propodeal lobes pointed apically; body slender, scape, propodeal spines and petiole longer (SI1 > 0.95, usually> 1.00, ESLI ≥ 0.45, PI1 > 1.60; indices do not apply to Myrmica gigantea) . . . . . 16

14
return to couplet #13
 * Very large, one of the largest known Myrmica species, HW > 1.60, AL > 2.50 mm. Very hairy species, number of standing hairs on petiolar node > 20. - Taiwan . . . . . Myrmica mirabilis


 * Smaller species, HW < 1.25, AL < 2.30 mm. Less hairy, number of standing hairs on petiolar node < 15 . . . . . 15

15
return to couplet #14
 * Mandibles with 11-13 teeth. - China: Sichuan, Hunan and Yunnan Prov. . . . . . Myrmica curiosa


 * Mandibles with 7-9 teeth. - Taiwan . . . . . Myrmica arisana

16
return to couplet #13
 * Surface between rugae on head and dorsal surface of waist is smooth or at most very finely superficially micropunctated, appearing shiny; head, alitrunk and waist usually with a similar coarse rugosity . . . . . 17


 * Surface between rugae on waist always distinctly and often coarsely punctated, appearing dull; surface of head usually is similarly punctated (except for Myrmica angulata); rugosity on head dorsum often is noticeably finer than that on alitrunk . . . . . 25

17
return to couplet #16
 * Whole head dorsum with almost straight, subparallel rugae, completely lacking reticulation, number of rugae between frontal carinae level with the eyes > 6 . . . . . 18


 * Head dorsum with distinctly sinuous rugae and reticulation, if reticulation not developed, number of rugae between frontal carinae level with the eyes < 6 . . . . . 19

18
return to couplet #17
 * Occipital and lateral margins of head with long standing hairs. Seen at magnification 100x surface of head weakly micropunctated. Pronotum coarsely reticulate. Head brownish-red, not strongly contrasting with the darker alitrunk. - China: Sichuan Prov. . . . . . Myrmica pararitae


 * Only occipital margin of head with long erect hairs. Seen at magnification 100x microsculpture on surface of head completely invisible. Pronotum with longitudinal rugae. Head yellow, strongly contrasting with the darker alitrunk. - Burma, Thailand . . . . . Myrmica ritae

19
return to couplet #17
 * Very large, the largest known Myrmica species, HW ≥ 1.80, AL ≥ 3.30 mm. - N Vietnam . . . . . Myrmica titanica


 * Smaller species, HW < 1.65, AL < 2.60 mm . . . . . 20

20
return to couplet #19
 * Scape, petiole and propodeal spines relatively short, SI1 0.90, PI1 1.50, ESLI 0.35. Quite big species, HW 1.62; AL 2.58 mm. - Burma . . . . . Myrmica gigantea


 * Scape, petiole and propodeal spines distinctly longer, SI1 ≥ 1.00, PI1 > 1.60, usually > 2.00, ESLI > 0.50. Relatively smaller species, HW < 1.50, AL < 2.55 mm . . . . . 21

21
return to couplet #20
 * Long standing hairs present only on occipital margin, genae and temples occasionally with an only few hairs. Frons with very coarse sculpture, having only four rugae between frontal carinae level with the eyes . . . . . 22


 * Both occipital and lateral margins of head with numerous long standing hairs.. Frons with various sculpture . . . . . 23

22
return to couplet #21
 * Alitrunk dorsum with numerous long standing hairs. Lateral sides of head slightly convex and occipital corners narrowly rounded, so that head,appears roughly subrectangular. - Isl. Pulo Laut (SE of Borneo) . . . . . Myrmica meryi


 * Alitrunk dorsum with a few scattered standing hairs. Lateral sides of head strongly convex and occipital corners widely rounded, barely marked, so that head appears roughly suboval. - Burma . . . . . Myrmica margaritae

23
return to couplet #21
 * Posterior half of head dorsum (from above the level of the eyes) with coarse reticulation, remainder with sinuous rugae; frons level with the eyes between frontal carinae with only 4 coarse rugae. Petiolar node and postpetiole, as well as sides of alitrunk, with coarse reticulation. - China: Guangxi Prov. . . . . . Myrmica sinensis


 * Head dorsum with sinuous rugae; coarse reticulation, if present, restricted to occiput; frons with various sculpture. Petiolar node and postpetiole, as well as sides of alitrunk, with coarse rugosity . . . . . 24

24
return to couplet #23
 * Frons between frontal carinae level with the eyes with 4 very coarse rugae. - Taiwan . . . . . Myrmica pulchella


 * Frons between frontal carinae level with the eyes with ≥ 6 finely rugae. - Taiwan, southern China, Northern Vietnam . . . . . Myrmica serica

25
return to couplet #16
 * Waist with fine sculpture, distinctly contrasting with much coarser sculpture on alitrunk . . . . . 26


 * Waist with coarser sculpture, similar to that on alitrunk . . . . . 27

26
return to couplet #25
 * Head shorter, mean CI 1.11, with narrowly rounded, well-marked occipital corners, appears subrectangular. Scape shorter, SI1 < 1.10. - China: Guangxi Prov. . . . . . Myrmica draco


 * Head longer, mean CI 1.19, with widely rounded, barely marked occipital corners, appears suboval. Scape longer, SI1 > 1.20. - Northern Vietnam . . . . . Myrmica schoedli

27
return to couplet #25
 * Surface of head dorsum between rugae not punctated, appears shiny, only waist with coarse rugosity and densely punctated, appears dull. - China: Guangxi and Hubei Prov. . . . . . Myrmica angulata


 * Surface of both head dorsum and waist between rugae punctated, appears dull . . . . . 28

28
return to couplet #27
 * Sculpture on head dorsum distinctly finer than that on alitrunk, frons between frontal carinae level with the eyes with 9 rugae, head shorter, CI 1.11. Petiole shorter, PI1 1.69; propodeal spines directed mainly backward, nearly horizontal. - China: Sichuan Prov. . . . . . Myrmica poldii


 * Sculpture on head dorsum similar to that on alitrunk, frons between frontal carinae level with the eyes with 6 rugae, head longer, CI > 1.15. Petiole longer, PI1 > 2.00; propodeal spines directed backward and upward, inclined at an angle more than 45°. - Northern Vietnam . . . . . Myrmica yamanei