The ant genus Tetramorium Mayr (Hymenoptera: Formicidae) in the Malagasy region — taxonomy of the T. bessonii, T. bonibony, T. dysalum, T. marginatum, T. tsingy, and T. weitzeckeri species groups
Author
Garcia, Francisco Hita
Author
Fisher, Brian L.
text
Zootaxa
2012
2012-07-04
3365
1
123
journal article
20762
10.11646/zootaxa.3365.1.1
1db9bc74-46dd-4263-9784-88a59bd05d59
11755334
6038900
Tetramorium ryanphelanae
Hita Garcia & Fisher
sp. n.
(figs 10, 23, 24, 25)
Holotype
worker,
MADAGASCAR
,
Antsiranana
,
Réserve Spéciale de l'Ankarana
,
22.9 km
224° SW Anivorano Nord
,
12.90889 S
,
49.10983 E
,
80 m
, sifted litter, tropical dry forest, BLF2972,
10.–16.II.2001
(
B.L. Fisher
et al.
) (
CASC
:
CASENT0454495
)
.
Paratypes
nine workers
with same data as holotype (
CASC
:
CASENT0454488
;
CASENT0454492;
CASENT0454498;
CASENT0454506;
CASENT0454508;
CASENT0454510; CASENT0454512;
CASENT0454514;
CASENT0454515)
;
seven workers
with same data as holotype but from ground nest and collection code BLF2992 (
CASC
:
CASENT0427964
;
CASENT0427965;
CASENT0427966); and
31 workers
from
Antsiranana
,
Réserve Spéciale de l'Ankarana
,
13.6 km
192° SSW Anivorano Nord
,
12.86361 S
,
49.22583 E
,
210 m
, sifted litter, tropical dry forest, collection codes BLF3010 and BLF3012,
16.–21.II.2001
(
B.L. Fisher
et al.
) (
BMNH
:
CASENT0441698
;
CASC
:
CASENT0401616
;
CASENT0401617;
CASENT0401618;
CASENT0401619;
CASENT0401620;
CASENT0401621;
CASENT0441560;
CASENT0441565;
CASENT0441566;
CASENT0441567;
CASENT0441576;
CASENT0441577;
CASENT0441578;
CASENT0441579;
CASENT0441582;
CASENT0441586;
CASENT0441588;
CASENT0441619;
CASENT0441621;
CASENT0441624;
CASENT0441624;
CASENT0441655;
CASENT0448303;
CASENT0448311;
CASENT0448345;
CASENT0448347;
CASENT0448367;
CASENT0448373;
MCZ
:
CASENT0441569
;
MHNG
:
CASENT0448330
;
NHMB
:
CASENT0441581
)
.
Diagnosis
The following character combination renders
T. ryanphelanae
recognisable within the
T. bessonii
group: short antennal scapes (SI 76–78); PSLI 28–33; absence of promesonotal suture; high nodiform petiolar node in profile with approximately parallel anterior and posterior faces, anterodorsal and posterodorsal angles at about same height, dorsum not tapering backwards posteriorly; presence of standing hairs on waist segments and first gastral tergite; and relatively long, appressed to decumbent pubescence on first gastral tergite.
Description
HL 0.68–0.88 (0.81); HW 0.70–0.90 (0.83); SL 0.54–0.68 (0.63); EL 0.15–0.21 (0.18);
PH
0.41–0.56 (0.49); PW 0.53–0.68 (0.62); WL 0.91–1.22 (1.09); PSL 0.21–0.28 (0.25); PTL 0.17–0.23 (0.20); PTH 0.31–0.37 (0.34); PTW 0.25–0.32 (0.28); PPL 0.22–0.27 (0.25); PPH 0.29–0.37 (0.33); PPW 0.31–0.42 (0.36); CI 101–104 (102); SI 76– 78 (77); OI 20–23 (22); DMI 56–59 (57); LMI 43–47 (45); PSLI 28–33 (30); PeNI 41–50 (46); LPeI 52–62 (59); DPeI 133–150 (142); PpNI 52–62 (58); LPpI 70–80 (74); DPpI 135–155 (146); PPI 122–132 (126) (15 measured). Head wider than long (CI 101–104). Anterior clypeal margin with distinct median impression. Frontal carinae well-developed, becoming weaker and fading out shortly after level of posterior eye margin. Antennal scrobes faint to absent, posterior and ventral margins never differentiated. Antennal scapes short, not reaching posterior head margin (SI 76–78). Eyes small to moderate (OI 20–23). Mesosomal outline in profile convex, dorsally transversely rounded, weakly to moderately marginate from lateral to dorsal mesosoma, promesonotal suture and metanotal groove absent; mesosoma comparatively stout (LMI 43–47). Propodeal spines elongate-triangular to spinose, long, and acute (PSLI 28–33). Propodeal lobes very small and broadly triangular. Petiolar node in profile high nodiform, anterior and posterior faces approximately parallel, anterodorsal and posterodorsal angles at about same height, dorsum not tapering backwards posteriorly; node in dorsal view not strongly transverse, between 1.3 to 1.5 times wider than long (DPeI 133–150), in lateral view between 1.6 to 1.9 times higher than long (LPeI 52–62). Postpetiole in profile rounded and weakly anteroposteriorly compressed, approximately 1.2 to 1.4 times higher than long (LPpI 70–80), in dorsal view between 1.3 to 1.6 wider than long (DPpI 135–155). Postpetiole in profile a bit less voluminous than petiolar node, in dorsal view approximately 1.2 to 1.3 times wider than petiolar node (PPI 122–132). Mandibles distinctly longitudinally striate; clypeus always with strong median longitudinal ruga and generally one weaker ruga at each side; remainder of head mostly unsculptured, cephalic dorsum between frontal carinae only with one well-developed longitudinal median ruga, remainder unsculptured, median ruga of same length as frontal carinae and diverging approximately at eye level into two rugae running to posterior clypeal margin; scrobal area, lateral and ventral head mostly unsculptured. Ground sculpture faint. Mesosoma, waist segments, and gaster unsculptured and smooth. Ground sculpture on whole body faint to absent. All dorsal surfaces of body generally with long, erect pilosity in combination with comparatively long appressed pubescence. Body colouration uniformly brown.
Notes
The distribution of the new species seems to be restricted to the northernmost tip of
Madagascar
, where it is generally found in tropical dry forests at elevations of
60 m
to
425 m
.
The southernmost localities are Foret d'Andavakoera and Foret de Binara, while the northernmost are Montagne des Français and Foret d'Orangea.
Due to its high nodiform petiolar node with anterodorsal and posterodorsal margins at approximately the same height,
T. ryanphelanae
cannot be misidentified with the three species that possess a much stronger anteroposteriorly compressed petiolar node in which the dorsum tapers backwards posteriorly (
T. artemis
,
T. bessonii
,
T. wardi
). The remaining two species are morphologically much closer to
T. ryanphelanae
, but can be clearly separated from each other.
Tetramorium orientale
, which is only known from the
holotype
, displays a distinct promesonotal suture, whereas this character is absent in
T. malagasy
and
T. ryanphelanae
. The distinction between these two morphologically comparatively similar species relies on antennal scape and propodeal spine lengths and gastral pilosity and pubescence. First,
T. malagasy
has comparatively shorter antennal scapes (SI 71– 74) and longer propodeal spines (PSLI 33–37) than
T. ryanphelanae
(SI 76–78; PSLI 28–33). More importantly though,
T. malagasy
has only very short and strongly appressed pubescence on the first gastral tergite while in
T. ryanphelanae
the gastral pubescence is comparatively long and appressed, and combined with few long erect hairs. Additional information about the differentiation between both species is provided above in the species description of
T. malagasy
. Caution is demanded in some specimens, which do not possess standing hairs on the first gastral tergite, since they could be misidentified as
T. malagasy
. However, this can be avoided by comparing antennal scape and propodeal spine lengths.
Etymology
The new species is named in honor of Ryan Phelan for her support to discover and identify life on earth.
Material examined
MADAGASCAR
:
Antsiranana
, Forêt d' Andavakoera,
21.4km
75° ENE Ambilobe,
4.6km
356° N Betsiaka,
13.11833 S
,
49.23 E
,
425 m
, rainforest,
15.XII.2003
(
B.L. Fisher
);
Antsiranana
, Forêt de Binara,
7.5 km
230° SW Daraina,
13.255 S
,
49.61667 E
,
375 m
, tropical dry forest,
2.XII.2003
(
B.L. Fisher
);
Antsiranana
, Forêt d'Orangea,
3.6 km
128° SE Remena,
12.25889 S
,
49.37467 E
,
90 m
, littoral rainforest,
22.–28.II.2001
(
B.L. Fisher et al.
);
Antsiranana
, Montagne des Français,
7.2 km
142° SE
Antsiranana
(=Diego Suarez),
12.32278 S
,
49.33817 E
,
180 m
, tropical dry forest,
22.–25.II.2001
(
G.D. Alpert
);
Antsiranana
, Réserve Analamerana,
16.7 km
123° AnivoranoNord,
12.80467 S
,
49.37383 E
,
225 m
, tropical dry forest,
3.XII.2004
(
B.L. Fisher
);
Antsiranana
, Réserve Analamerana,
28.4 km
99° Anivorano-Nord,
12.74667 S
,
49.49483 E
,
60 m
, tropical dry forest,
5.XII.2004
(
B.L. Fisher
);
Antsiranana
, Réserve Spéciale d'Ambre,
3.5 km
235° SW Sakaramy,
12.46889 S
,
49.24217 E
,
325 m
, tropical dry forest,
26.I.2001
(
B.L. Fisher et al.
);
Antsiranana
, Réserve Spéciale de l'Ankarana,
7 km
SE Matsaborimanga,
12° 54' S
,
49° 07' E
,
150 m
, rainforest & tropical dry forest,
27.–28.XI.1990
(P.S. Ward);
Antsiranana
, Réserve Spéciale de l'Ankarana,
22.9 km
224° SW Anivorano Nord,
12.90889 S
,
49.10983 E
,
80 m
, sifted litter, tropical dry forest,
10.–16.II.2001
(
B.L. Fisher et al.
);
Antsiranana
, Réserve Spéciale de l'Ankarana,
22.9 km
224° SW Anivorano Nord,
12.90889 S
,
49.10983 E
,
80 m
, tropical dry forest,
12.II.2001
(
G.D. Alpert
);
Antsiranana
, Réserve Spéciale de l'Ankarana,
13.6 km
192° SSW Anivorano Nord,
12.86361 S
,
49.22583 E
,
210 m
, tropical dry forest,
16.–21.II.2001
(
B.L. Fisher et al.
);
Antsiranana
, Réserve Spéciale de l'Ankarana,
13.6 km
192° SSW Anivorano Nord,
12.86361 S
,
49.22583 E
,
210 m
, tropical dry forest,
19.–20.II.2001
(
G.D. Alpert
);
Antsiranana
, Diego Surez, above Sakaramy,
500 m
,
12.II.1972
(
W.L. & D.E. Brown
).