Systematic Entomology (1994) 19, 159-175

Adetomyrma, an enigmatic new ant genus
from Madagascar (Hymenoptera: Formicidae),
and its implications for ant phylogeny

PHILIP S. WARD Department of Entomology, University of California, Davis, California, U.S.A.

Abstract. Adetomyrma venatrix, representing a new genus and species of ant,
is described from a single collection of twenty-one workers from Zombitse
Forest, in western Madagascar. Remarkable features of its morphology include:
(i) absence of a petiole in dorsal view (abdominal tergum 3 lacking a dorsally
differentiated pretergite), (ii) gaster large and expanded posteriorly, all terga
and sterna unfused and without constrictions, (iii) absence of eyes, and (iv)
presence of a very large sting (larger, in relation to body size, than that of any
other known ant). Adetomyrma does not possess any of the derived features
heretofore said to characterize the existing ant subfamilies. Morphological
evidence suggests, however, that it is cladistically a member of the ponerine
tribe Amblyoponini despite the absence of apomorphic abdominal characters
(tergosternal fusion of abdominal segments 3 and 4) seen in all other Ponerinae
and in the more inclusive 'poneroid group' of subfamilies. Whether Adetomyrma
shows primitive absence of such characters or secondary reversal to an unfused
state has important implications for the higher phylogeny of the ants. There is
insufficient evidence to choose decisively between these two alternatives, but in
either case the monophyly of the ant subfamily Ponerinae becomes doubtful.

Introduction

Madagascar supports an extraordinary fauna and flora,
notable for its diversity and endemism (Battistini & Richard-
Vindard, 1972; Jolly et al., 1984). Apparently isolated
from the African mainland throughout most or all of the
Tertiary (Rabinowitz et al., 1983; Tattersall, 1982), the
island contains many taxa that are deemed 'primitive' in
morphology and basal in phylogenetic position (Martin,
1990; Stiasnny, 1992). The ant fauna of Madagascar is
imperfectly known — the last comprehensive treatment
appeared over a hundred years ago — but it includes at
least four endemic (out of approximately forty indigenous)
genera, and a level of species endemism exceeding 90%
(Forel. 1891; Wheeler, 1922; Brown, 1975, 1978; Bolton,
1979. 1981; Olson & Ward, 1994; Ward, unpubl.). The
absence from Madagascar of certain dominant Afrotropical
taxa such as driver ants (Aenictus and Dorylus) and weaver

Correspondence: Dr P. S. Ward, Department of Entomology,
University of California, Davis, CA 95616, U.S.A.

ants (Oecophylla) has doubtless permitted the persistence,
and in some instances the diversfication, of ant taxa that
are less common or absent elsewhere.

During recent field work on the island I encountered
several workers of a small, pale subterranean ant that proved
to be unlike any other known formicid. This ant appears to
belong to the 'primitive' ponerine tribe Amblyoponini. An
analysis of its morphology upsets recent views about the
higher phylogeny of ants and suggests that the subfamily
Ponerinae is para- or polyphyletic.

Materials and Methods

Collection abbreviations follow those of Ward ( 1989) and
Arnett et al. (1993). The following metric measurements
(in mm) and indices are cited: HW (head width: maximum
width of head, measured in dorsal view), HL (head length:
length of head, measured in dorsal view, from the anterior
clypeal margin to a line drawn across the posterior margin
of the head), SL (scape length: maximum measurable
length of the scape, excluding the basal neck), PW (prono-
tal width: maximum width of the pronotum, measured in

159

160 Philip S. Ward

dorsal view), DPW (dorsal petiole width: maximum width
of abdominal segment 2, measured in dorsal view), LHT
(length of the metatibia: maximum measurable length of
the metatibia), CI (cephalic index: HW/HL) and SI (scape
index: SL/HW).

Since taxonomic placement of Adetomyrma proved
challenging, I surveyed character variation across a wide
range of potential relatives including Apomyrma, Lepta-
nilla, the principal genera of the 'doryline section' (Bolton,
1990b), and representative genera of the five tribes in the
Ponerinae (Amblyoponini, Ectatommini, Platythyreini,
Ponerini and Typhlomyrmecini). Character systems that
proved to be of particular significance included: develop-
ment of specialized setae on the anterior clypeal margin;
position and shape of the metapleural gland orifice and
associated structures; configuration of the metacoxal
cavities; and relative position, shape and fusion of the
petiolar (second abdominal) sclerites.

To facilitate discussion the collective term 'doryline
section' (Bolton, 1990b) is used to refer to the subfamilies
Cerapachyinae, Leptanilloidinae and the army ants (Ecito-
ninae, Aenictinae, Aenictogitoninae, Dorylinae), and
'poneroid group' to refer to the 'doryline section' plus
Apomyrminae, Leptanillinae and Ponerinae. The ad-
jectival nouns 'ponerine' and 'poneroid' pertain to the
Ponerinae and the 'poneroid group', respectively.

Descriptive taxonomy
Adetomyrma gen. n.

Type species: Adetomyrma venatrix sp. n.

Worker diagnosis (putative autapomorphies of the genus
are marked with an asterisk; some of these designations
are better understood in the context of the phylogenetic
position of Adetomyrma, discussion of which is deferred to
a later part of the paper):

1.  Twelve antennal segments.

2.  Mandibles subfalcate, crossing at rest, and without
differentiated basal and masticatory margins (Figs 7, 12);
inner margin with relatively few teeth (5 — 6 teeth in the
only known species).

3.* Palpal segmentation reduced (palp formula 3,3 in
the only known species).

4.* Clypeus reduced to a narrow strip (dorsal view) and
deflected ventrally.

5.  Anterior clypeal margin with a row of stout, conical
setae (Fig. 12).

6. Antennal sclerite (or torulus) raised medially, i.e. not
horizontal, and fused with the laterally expanded frontal
lobes.

7.  Frontal lobes weakly developed, only partially cover-
ing the antennal insertions in dorsal view (Figs 6, 7), the
maximum distance between their outer margins about
14% of HW.

8.* Compound eye lacking.

9. Promesonotal suture unfused and flexible.

10.* Metanotum not evident and mesonotum reduced in
size, much shorter than the basal face of the propodeum
(Fig. 4).

11.  Metacoxal cavities tightly encircled by cuticle but
the endpoints not fused (Fig. 18); metasternal invagination
broad and shallow, extending anteriorly between the
metacoxal cavities no more than about one third the cavity
diameter.

12.  Propodeal spiracle large, circular, in an upper and
posterior position (Fig. 24), almost contiguous with the
visible upper margin of the metapleural gland bulla.

13.  Metapleural gland well developed, the bulla forming
a large conspicuous patch on the lower lateral and posterior
faces of the mesosoma, below and behind the propodeal
spiracle.

14.   Metapleural gland orifice (or meatus) opening
posterodorsally, near the centre of the bulla, above a
posterolateral swelling of the metapleuron (Figs 24, 30);
orifice not overhung by a conspicuous cuticular flap nor
confluent with an anteriorly directed, longitudinal groove
or impression.

15.* Tergum and sternum of abdominal segment 2 fused
anteriorly but not posteriorly; tergosternal suture com-
pletely obliterated in the region of fusion (Fig. 36).

16. Unfused portion of abdominal sternum 2 triangular,
terminating anteroventrally in a well-developed tooth (just
posterior to the point of tergosternal fusion), and flanked
on either side by a differentiated laterotergite (Fig. 36).

17.* Helcial tergite (pretergite of abdominal segment 3)
poorly developed, not set off from the rest of tergum 3
by a constriction, in consequence of which no petiole
discernable in dorsal view (Figs 3,4).

18.  Helcial sternite thin, straight (not bulging ventrally),
overlapped ventrolaterally by the lower arms of the helcial
tergite (Fig. 41).

19.   Helcial sternite narrower than the poststernite of
abdominal segment 3, and positioned much higher than it
so that a ventral petiolar constriction is seen in lateral view
(Fig. 2).

20.*? Helcial sternite strongly bound by connective
tissue to the posterodorsal margin of abdominal sternite 2.
(In two of four dissections that were performed part of the
helcial sternite and adjacent poststernite broke from the

rest of abdomen 3 and remained attached to the inside of
the petiolar venter; see Fig. 36.)

21.*? Tergum and sternum proper of abdominal segment
3 unfused, but helcial tergite tightly embracing the lateral
margins of the helcial sternite and apparently fused with it.

22.*? Tergum and sternum of abdominal segment 4
unfused and without differentiated presclerites.

23.* Abdominal spiracles 5, and sometimes 6, exposed
under normal gastral expansion.

24.* Metasoma large and expanded posteriorly, meta-
somal length about 1.6 times mesosomal length.

25.  Pygidium simple, with posterior extremity rounded
and hood-like, neither denticulate nor heavily sclerotized
or otherwise modified.

26.  Gonostylus long and distinctly 2-segmented.

27.  Sting very large and barbed, valve chamber small

and poorly differentiated from sting shaft; lancet with 7
barbs, sting shaft with 4 pairs of barbs.

28.  Sting furcula present, well developed, with dorsal as
well as lateral (ventral) arms.

29.  Tibial spurs 1,1,2; anterior metatibial spur small,
posterior spur large, subtriangular and sinuous, its lower
margin pectinate, upper margin barbulate; mesotibial spur
weakly barbulate, flanked by a minute remnant of the
second (anterior) spur.

30.  Apical segment of metatarsus enlarged, longer and
wider than each of the three preceding segments.

31.  Tarsal claws simple.

32.  Metabasitarsal gland (Hölldobler & Palmer, 1989)
absent.

Unique features of Adetomyrma workers include the
weakly differentiated helcial tergite and consequent ape-
tiolate appearance in dorsal view; the large and posteriorly
expanded gaster all of whose segments are unfused and
(except abdominal segment 3) without differentiated
presclerites; and the enormous sting which is larger in
relation to body size than that of any other ant. Because
the valve chamber is not well differentiated from the
sting shaft, Kugler's (1978) 'index of sting reduction' (IR
= shaft length/PW x 100) cannot be calculated precisely.
Nevertheless Adetomyrma has a sting length/LHT ratio of
1.72—1.77 and an approximate IR of 190. These values are
well above those reported for other ants (Kugler, 1978,
1980, 1991, 1992), the nearest being Amblyopone pallipes
with an IR of 119 (Kugler, 1978). The dentiform clypeal
setae, absence of eyes, configuration of the metapleural
gland orifice, structure of the petiole and exposure of
abdominal spiracle 5 are also distinctive features, that
occur in this combination in no other known ant.

Adetomyrma presents a curious mix of ancestral and
derived traits. The former include a freely articulating
pronotum and mesonotum, unfused metacoxal cavities, a
well-developed furculate sting, and an apparently primitive
configuration of abdominal segments 3 and 4 (but see
discussion below). Derived features include the reduced
eyes, mouthparts, and mesonotum; the anterior fusion
of abdominal tergum and sternum 2; and the enlarged
metasoma. A discussion of the taxonomic position of
Adetomyrma is given after the species description.

Adetomyrma venatrix sp.n. (Figs 1-7,12,13, 18, 24, 30,

36, 41)

Holotype worker. MADAGASCAR, Zombitse Forest,
along Route Nationale 7. 15 km E Sakaraha, 760 m, 22°54'S,
44°41'E, 15 February 1993, P. S. Ward no. 11932, ex rotten
log, tropical dry forest (MCZC).

Paratypes. Series of twenty workers, same data as
holotype (to be deposited in ANIC, BMNH, LACM,
MCZC, MNHN, PBZT, PSWC, UCDC).

Adetomyrma, a new ant genus from Madagascar 161

Worker measurements (n = 13). HW 0.40-0.49, HL
0.48-0.56, SL 0.29-0.34, PW 0.28-0.33, DPW 0.20-
0.27, LHT 0.32-0.37, CI 0.83-0.90, SI 0.66-0.73.

Description (worker). Small (HW < 0.50 mm), pale
and blind. Mandibles subfalcate, without distinct basal
and masticatory margins (Fig. 12); inner margin with 3 or
(more commonly) 4 teeth, equally spaced and lying in the
same plane as the front of the head, followed by a gap
(0.05-0.06 mm) and two longer (subapical and apical)
teeth which, as a consequence of the curvature of the
mandibles, lie in the dorsoventral plane when the man-
dibles are closed. Closed mandibles with apices over-
lapping. Clypeus very short, its principal surface deflected
vent rally, anterior margin broadly convex and furnished
with a row of about 20 small, specialized, conical setae
(Figs 7, 12). Frontal carinae short, low, expanded laterally
as small frontal lobes that over no more than about a third
of the antennal insertions (dorsal view). Medial portion of
the antennal sclerite (torulus) upturned and fusing with
the frontal carinae. Scape notably shorter than head length
(SL/HL 0.59-0.61); first funicular segment c. 2.3 times
longer than broad, and approximately equal to the com-
bined length of the next three funicular segments; funicular
segments 2-8 broader than long, segments 8-11 becom-
ing gradually enlarged but not forming a distinct club.
Terminal funicular segment c. 2.5 times longer than penul-
timate segment, and about half the scape length. Head
subquadrate (Fig. 6), longer than wide (CI 0.83-0.90),
widest near the mandibular insertions; sides slightly con-
vex, converging posteriorly and rounding into the concave
posterior margin. Mesosoma dorsum somewhat flattened
in profile, lateral margins rounded; in dorsal view pro-
notum longer than broad, with convex sides, mesonotum
very short and twice as wide as long (Fig. 4). Basal (=
dorsal) face of propodeum narrower than pronotum,
about 1.5 times longer than wide, with subparallel sides
that converge slightly towards the mesonotum; basal face
of propodeum about 2.5 times the length of the declivitous
face, and rounding gently into the latter (Figs 1, 24).
Metapleuron fully fused with propodeum, the two not
distinguishable in lateral view. Metapleural gland bulla
conspicuous, manifested as a large circular patch on the
lower posterolateral corner of the mesosoma, its dorso-
ventral height about two-thirds the length of the declivitous
face of the propodeum. Inferior propodeal ('metapleural')
lobes essentially undeveloped. Abdominal tergum 2 c.
1.4 times broader than long, in dorsal view. Abdominal
sternum 2 with a conspicuous subpetiolar process, shaped
like an irregular axe blade (Fig. 2). Abdominal sternum 3
with anteroventral surface evenly convex, lacking pro-
tuberant ridges near the helcium.

Mandibles smooth with scattered punctures. Most of
body smooth and shining; head and mesosoma dorsum
with numerous piligerous punctures (c. 0.010—0.015 mm
diameter) separated by one to several times their diam-
eters, densest on the head (except for a smooth puncture-
free median strip). A few scattered punctures on abdominal
tergum 2, remainder of metasoma with small, less con-

162 Philip S. Ward

Figs 1-7. SEM micrographs of Adetomyrma venatrix worker. In these and subsequent figures the scale bars are approximately the
indicated lengths in microns (µm) 1. left lateral view of body (composite of two micrographs of the same specimen) 2. Lateral view of
petiole (abdominal segment 2); 3, 4. dorsal views of body; 5, left lateral view of gaster; 6. dorsal view of head: 7. oblique anterodorsal.
view cf he-id.

sulcuous punctalae preceded on the exposed portions or
the interior margins of each sclerite by fine transverse
reticulate-striolate sculpture. Sides of propodeum and
metapleuron with weak reticulations. Body with a rather

dense cover of pale erect and suberect hairs; more than 30
standing hairs visible in profile on the mesosoma dor-
sum: anterior margin of clypeus with a row of long (up to
0.12mm), slender, curved setae (dorsad of the specialized

Adetomyrma, a new ant genus from Madagascar 163

Figs 8 - 13. Anteroventral views (close-up on right) of worker clypeus, with specialized setae. 8. 9. Onychomyrmex doddi Wheeler: 10, 11

Prionopelta ?amabilis Borgmeier: 12, 13. Adetomyrma venatrix. Note that in Onychomyrmex most setae adorn the clypeus but one pair
occurs behind on the labrum (Fig. 9)

tooth like setae) that exceed the closed mandibles; erect
setae also present on the scapes, funiculi and extension
surfaces of the tibiae. Colour: light yellow-brown, with
narrow darker bands at the posterior margins of abdominal
segments 2 to 4 or 5.

Comments. Features of Adetomyrma venatrix that are
likely to be species-specific include the small size, man-
dibular dentition, body sculpture, dense standing pilosity,
size and density of clypeal setae, and shape of the antero-
ventral petiolar tooth.

164 Philip S. Ward

Figs. 14-17. Anteroventral views (close-up on right) of worker clypeus. 14, 15. Amblyopone oregonensis (Wheeler); 16. 17, Apomyrma
stygia. In Apomyrma the peg-like setae are located on the labrum not the clypeus.

Larva. A single ant larva, recovered from the vial con-
taining the workers, may be that of A. venatrix. It is 2.46 mm
long and essentially "leptanilloid" (Wheeler & Wheeler,
1976) in shape, i.e. long, slender, and club-shaped, widest
neat the posterior end (at abdominal segments 8 and 9).
The thorax is slender and curved ventrally. The body hairs
are numerous, short and inconspicuous. No thoracic pro-
tuberances or specialized dorsal tubercles were detected.

Biology. The twenty-one workers were collected from
the lower surface of a rotten log. at the log/soil interface,
in a tract of tropical dry forest in western Madagascar.
The workers appeared to be foraging as a group, much in
the manner of several small Cerapachys species that are
characteristic of the dry forest of western Madagascar,
although it is possible that they were recruiting to a prey
item (not seen). Unfortunately time did not permit a
detailed search for the colony. One of the workers stung
my finger and this produced a noticeable stinging sensation
(and later a slight swelling that persisted for several days)
despite the minute size of the worker. It seems reasonable
to surmise thai Adetomyrma venatrix is a specialized

predator or ground-dwelling arthropods. The apparent
group foraging behaviour is suggestive of the habits of
leptanilline ants (Masuko. 1990) and true army arm (Got-
wald. 1982) and leads to the prediction that the queen of
Adetomyrma will prove to be a morphologically specialized
wingless female,

The collection took place after a period of exceptionally
heavy rains on this part of the island that effectively broke
a 2-year drought. It seems likely that this ant is usually
subterranean and elusive, and that its discovery was aided
by the wet soil conditions. A Winkler litter sample taken
at the same site faded to produce additional material of
Adetomyrma.

The Zombitse Forest where Adetomyrma was found (see
illustration in Tattersall. 1982: 31). although falling within
the bounds of what is considered tropical dry forest, is
nevertheless more [[...]] than most of the dry forests of
western Madagascar. Moreover, the forest is under severe
threat from human activities. Large swaths of the forest
along Route Nationale 7 east of Sakaraha have been
destroyed by slash-and-burn agriculture. After a few cycles

Adetomyrma, a new ant genus from Madagascar 165

Figs 10-23. Worker metacoxal cavities. 18. Adetomyrma venatrix: 19. Prionopelta ?amabilis 20. Mystrium voeltzkowi Forel; 21,
Typhlomyrmex rogenhoferi, 22. Rhytidoponera chalybaea Emery: 23. Myrmica incompleta Provancher.

of corn and other crops the land becomes a degraded
savannah woodland. It seems certain that the collection
site for Adetomyrma which is located no more than 100m
from the main road will suffer the same fate unless urgent
protective measures are taken.

Relationship to other formicids

Adetomyrma presents something of a puzzle. At first glance
it would appear to be unplaceable in any of the existing ant
subfamilies since it possesses none of the derived traits
that individually characterize them (Baroni Urbani et al.

166 Philip S. Ward

Fig. 24 -29. Lateral views of worker mesosoma, posterior end; legs and metasoma removed (except in Fig. 24). 24. Adetomyrma venatrix;
25. Prionopelta ?amabilis; 26. Onychomyrmex doddi; 27. Typhlomyrmex rogenhoferi; 28. Rhytidoponera chalybaea; 29. Myrmica

incompleta.

1992; Bolton, 1994), In Bolton's (1994) subfamily key,
for example, it stalks at couplet 11 — a terminal couplet
for Apomyrminae and Ponerinae (part) — because it dis-
plays a mixture of features from both lugs of the couplet.
The lack of tergosternal fusion of abdominal segment 4
would seem to preclude placement of Adetomyrma in the

Ponerinae. At the same time Adetomyrma exhibits almost
none of the distinctive characteristics of the 'doryline
section' of subfamilies (Bolton, 1990b) such as a horizontal
torulus. protruding helcial sternite specialized pygidium.
reduction/loss of furcula, metatibial gland, or cuticular
flap over the metapleural gland. The exposed spiracle on

abdominal segment 5 is reminiscent of the greater exposure
that occurs, presumably convergently, in the doryline
section. Finally, the unfused condition of abdominal
segment 3 in Adetomyrma indicates that it does not even
belong to the more inclusive 'poneroid group' (Bolton,
1990b), i.e. that group of subfamilies, comprising Poner-
inae, Leptanillinae, Apomyrminae and the 'doryline
section', whose workers show tergosternal fusion of ab-
dominal segment 3 and all castes of which exhibit fusion
of the presclerites of the same segment (Bolton, 1990b;
Ward, 1990; Baroni Urbani et al., 1992). Since Adetomy-
rma has an apparently fused helcium (presclerites 3) this
could imply that it is in a basal position, perhaps as a sister
of the entire poneroid group.

A survey of additional character systems, beyond those
used for subfamily characterization, became necessary for
clarifying the phylogenetic affinities of Adetomyrma.
Focussing in particular on the morphology of the clypeal
setae, metapleural gland, metacoxal cavities and petiolar
sclerites, this survey revealed striking similarities (docu-
mented below) between Adetomyrma and members of the
ponerine tribe Amblyoponini, but not between Adetomyrma
and any other ants. The results support placement of
Adetomyrma in this tribe, and hence in the subfamily
Ponerinae, despite the absence of tergosternal fusion.

Redefinition of the Amblyoponini

Long considered a rather primitive group of ants, possibly
reflective of an early stage in ant evolution (Wilson, 1971;
Hölldobler & Wilson, 1990), the Amblyoponini were well
characterized by Brown (1960; see also Brown, 1974a, b;
Gotwald & Lévieux, 1972) but they have not heretofore
been defined explicitly in terms of derived characters
that would signify their monophyly. The characterization
given below refers to all currently recognized, extant
amblyoponine genera for which the worker caste is known
(i.e. Amblyopone, Concoctio, Mystrium, Myopopone,
Onychomyrmex and Prionopelta). These were compared
to a representative range of taxa in other ponerine tribes
(Ectatommini. Platythyreini, Ponerini, Typhlomyrmecini)
as well as to Apomyrma and the principal leptanilline and
doryline section genera. In the diagnosis below, apparent
apomorphic conditions are marked with an asterisk. Some
of these are unique, others have appeared convergently in
other ant groups, as discussed below. A comparison with
Adetomyrma appears after the diagnosis.

Tribe Amblyoponini Forel, 1893

1.* Worker, queen. Anterior clypeal margin with a row
of specialized, stout setae which give it a denticulate
appearance (Figs 8—11, 14, 15); this may be accentuated
by the setae arising from cuticular projections (Mystrium,
some Amblyopone). The setae are secondarily reduced in
some species, lost in Amblyopone mutica (Santschi).

2.*? Worker, queen. Mandibles overlapping at their tips
when closed and typically, but not always, without distinct

Adetomyrma, a new ant genus from Madagascar 167

basal and masticatory borders. Differentiated borders can
be seen in Concoctio and some Amblyopone, however, so
the groundplan for the tribe is uncertain.

3.* Worker, queen. Palp formula 5,3, with reductions
therefrom (Brown, 1960).

4.   Worker, queen. Twelve antennal segments, with
uncommon secondary reduction to as few as 9 and 7.

5.   Worker, queen. Antennal sclerite (torulus) raised
medially and fusing with the overlapping frontal lobes.

6.* Worker. Compound eyes reduced or, less commonly,
absent.

7.* Worker, queen. Eyes, when present, situated behind
the middle of the sides of the head.

8. Worker. Promesonotal suture unfused.

9.* Worker. Mesonotum short and transverse, on a
flattened mesosoma, shorter than the basal (= dorsal) face
of the propodeum, usually much so.

10.* Worker, queen, male. Metacoxal cavities encircled
by cuticle, the endpoints meeting broadly but not fused
(Figs 19, 20). Fusion occurs as a secondary development
within the tribe, in Onychomyrmex and possibly others.

11.* Worker, queen. Metapleural gland orifice directed
predominantly dorsally and posteriorly, on a curved sur-
face mesad of a posterolateral swelling or plate; orifice
plainly visible, as a thin crescentic cavity, in posterior
view; no guard hairs arising from the posterolateral swell-
ing (Figs 25, 26, 31, 32). The metapleural gland orifice of
Myopopone is somewhat divergent, opening laterally as
well as posterodorsally.

12.* Worker, queen. Petiole (abdominal segment 2)
shape characteristic: essentially apedunculate, with a steep,
broad anterior face and a flat dorsal face that extends to
the posterodorsal margin without descending into a distinct
posterior face.

13.* Worker, queen, male. Abdominal sternum 2 with
distinctive configuration: fused anteriorly with the tergum,
but not fully fused posteriorly, i.e. with some free play
between the sternite and adjacent tergite; posterior portion
of sternum 2, i.e. section posterior to the region of de-
finitive fusion, typically triangular or pyriform in shape
(ventral view), its anterior apex occurring at a 'pinch
point' marked by the approximate convergence of three
structures: the laterotergite (see 14 below), the anterior
termination of the (usually well developed and antero-
dorsally undercut) ventral petiolar tooth, and the lower
margins of the collar-like peduncular flange that encircles
the tergum anteriorly (Fig. 37); very rarely (e.g. A. mutica)
the petiolar tooth and peduncular flange absent.

14.*? Worker, queen, male. Abdominal tergum 2 with a
distinct laterotergite which parallels the posterior portion
of the sternum, forming a hinge joint with it; laterotergite
broad posteriorly, narrowing anteriorly and terminating at
the 'pinch point' near the lower margins of the collar-like
peduncular flange (Fig. 37). Laterotergite reduced/lost in
Prionopelta (Fig. 38) and in most Onychomyrmex.

15.*? Worker, queen, male. Petiole broadly attached to
upper margins of abdominal segment 3 and helcial sternite
broad. A significant narrowing of the broad dorsal attach-
ment occurs only in the aberrant Amblyopone mutica.

168 Philip S. Ward

Figs. 30 - 35. Posterior views of worker mesosoma, legs and metasoma removed. 30. Adetomyrma venatrix; 31. Prionopelta amabilis;

32. Onychomyrmex doddi; 33. Typhlomyrmex rogenhoferi; 34. Rhytidoponera chalybaea; 35. Myrmica incompleta.

16.  Worker, queen, male. Abdominal segment 3: ter-
gosternal fusion of presclerites and postsclerites,

17.   Worker, queen. Abdominal segment 4: differen-
tiation of presclerites and tergosternal fusion of the entire
segment.

18.*7 Worker, queen, male. Absence of stridulatory file
on abdominal tergum 4.

19. Worker. queen. Pygidium simple.

20.  Worker, queen. Sting apparatus well developed,
furcula present.

Adetomyrma, a new ant genus from Madagascar 169

Figs.36 - 40. Ventral views of worker petiole. 36. Adetomyrma venatrix; 37. Amblyopone oregonensis; 38. Prionopelta amabilis;

39. Apomyrma stygia ; 40. Typhlomyrmex rogenhoferi.

21. Worker, queen, male. Tibial spurs 1.2.2. with re-
ductions therefrom.

22.* Worker, queen. Posterior metatibial spur stout
subtriangular and curved (Hashimoto, 1991 b), its lower
margin pectinate and upper margin barbulate.

23. Worker, queen, male. Tarsal claws simple.

Some of the starred features listed above (e.g. reduction
and position of ine compound eyes: simple tarsal claws)
appear repeatedly in other ant groups and hence have
limited phylogenetic value. Other features, such as the
absence of a stridulatory file and the broad attachment
of the petiole to the succeeding segment, are possibly
pleomorphic. This is almost certainly true of inc presence
of a laterotergite on abdominal tergum 2 (also seen, for
example, in Myrmecina and some cerapachyines and other
ponerines) but the particular 'pinch point' arrangement of

the laterotergite, the ventral petiolar tooth, and the ped-
uncular* flange is more or less confined to Amblyoponini.
A ventral petiolar tooth and a peduncular flange are also
seen in many other ponerines, but their shape and position
in Amblyoponini are distinctive. The petiolar tooth, in
particular usually protrudes anteroventrally with the result
that, in lateral profile, a notch-like incision is observed at
its anterior junction with the sternum proper. Also com-
pelling as synapomorphies are the specialized dentiform
clypeal setae which appear to be unique to the tribe: the
particular configuration of the metapleural gland which is
not duplicated elsewhere: the shape of the petiole, which
is rarely seen in other ants (Typhlomyrmex rogenhoferi
Mayr and a few cerapachyines approach this condition);
and the broad but primitively unfused connection between
the sclerites encircling the metacoxal cavities.
As far as known, all amblyoponines are cryptic in their

170 Philip S. Ward

Figs. 41 - 44. Anterior views of worker helcia. 41. Adetomyrma venatrix; 42. Mystrium voeltzkowi; 43. Prionopelta ?amabilis; 44.

Typhlomyrmex rogenhoferi.

foraging habits and specialized as predators on arthropods,
especially centipedes, living in soil or rolling wood (Brown,
1960; Gotwald & Lévieux, 1972; Hölldobler & Wilson,
1986; Masuko, 1986; Ito, 1993) The shape of the man-
dibles, the powerful sting, and the dentiform clypeal
(sometimes also labral) setae no doubt assist physically in
prey capture (Brown, 1960), although the clypeal setae
probably also have a sensory function.

Excluded from Amblyoponini

1. Apomyrma, known from the single species Apomyrma
stygia Brown, Gotwald & Lévieux (1971), was originally
placed in the Amblyoponini but later transferred to the
Leptanillinae by Bolton (1990a) and then given subfamily
status, as Apomyrminae in Baroni Urbani et al. (1992).
The clypeal margin of the Apomyrma worker is not adorned
with specialised setae but there is a double row of similar,
presumably analogous (see also Gotwald & Lévieux, 1972)
peg-like setae on the labrum. Note that these are different
in shape than those of die Amblyoponini (compare Figs.

8-11, 14 -17). Nevertheless dentiform setae are round on
both the labrum and the clypeal margin in Onychomyrmex
(Fig. 9) and some Amblyopone, suggesting a possible link
between the characters. Protanilla, a leptanilline genus,
also possesses a pair of stout setae on the labrum (Bolton,
1990a) but none on the clypeus. Apomyrma workers have
no eyes and those of (he queen are placed in a posterior
position on the head in agreement with Amblyoponini.
With respect to the remaining putative synapomorphies of
Amblyoponini, however, Apomyrma exhibits differences;
it has a fully closed metacoxal cavity surrounded by a dis-
tinct annulus; metapleural gland orifice opening postero-
laterally, under a dorsal cuticular flap; non-amblyoponine
petiole shape: sharp constriction between the petiole and
abdominal segment 3: and an isolated posterior petiolar
sternite that is much reduced in size, although flanked by
apparent laterotergites (Fig. 39). It must be admitted,
however, that most of these conditions could be derived
from those seen in Amblyoponini (Amblyopone mutica
provides an uncanny example of a petiole tending towards
the Apomyrma condition.) The same could be said for the
horizontal toruli, forward-placed spiracle on abdominal

tergum 3, palp formula of 2,2, and transverse sulcus behind
the helcial sternite (see Bolton, 1990a: 280). Hence a close
relationship between these two cannot be ruled out. The
Amblyoponini might even be paraphyletic relative to
Apomyrma (and Leptanillinae), although the morphology
of the metapleural gland and gaster suggests otherwise.

2. The ponerine genus Typhlomyrmex, placed in its own
tribe but sometimes considered a possible relative of
Amblyoponini (Brown, 1974b), has no specialized clypeal
setae, a metapleural gland whose orifice opens dorso-
lateraly and is not visible in a strict posterior view (Figs 27,
33), open metacoxal cavities whose encircling cuticle does
not overlap broadly (Fig. 21), and a differently shaped
petiolar sternite (Fig. 40). Typhlomyrmex also lacks a
petiolar laterotergite and the broad attachment of the
petiole to the postpetiole. Brown (1965) cites additional
differences between Typhlomyrmex and Amblyoponini in
wing venation and larval mandibles.

Comparison of Adetomyrma with Amblyoponini

Unlike Apomyrma or Typhlomyrmex, Adetomyrma
exhibits almost all of the diagnostic features (derived and
primitive) of the Amblyoponini. The more important
commonalities are considered first.

1.  The worker of Adetomyrma has specialized stout,
clypeal setae which are similar in shape, external mark-
ings and location to those of the Amblyoponini (compare
Figs 8—15). Such clypeal setae are not known in other
poneroids.

2.  The mesonotum of the Adetomyrma worker is short
and transverse, much shorter than the propodeum and
only weakly distinguishable from the latter, as in many
amblyoponines.

3.  In Adetomyrma the metacoxal cavities are open, i.e.
not surrounded by fused sclerites, but the endpoints of
the sclerites overlap broadly, as in most amblyoponines
(Figs 18—20). This stands in contrast to the condition in
the doryline section in which the metacoxal cavities are
fully closed. Conversely, the tight embrace of the cavities
places Adetomyrma closer to the Amblyoponini than to
Typhlomyrmex and the more generalized ectatommines,
which have more open cavities (Figs 21, 22).

4.  The arrangement of the metapleural gland orifice in
Adetomyrma - opening posterodorsally above a swelling
on the posterolateral extremity of the metapleuron, visible
in posterior view as a crescent-shaped slit, and lacking
guard hairs — is very similar to that seen in Prionopelta
and Onychomyrmex (compare Figs 24—26, 30—32), and
different from the condition in non-amblyoponine poner-
oids (Figs 27, 28, 33, 34).

5. Adetomyrma has a petiole whose lateral profile (Fig. 2)
is typical of the tribe. There is also a very broad attachment
of the second abdominal segment to the third, although
this may be a primitive trait.

6.   The petiolar sternite of Adetomyrma conforms to
the above description for the Amblyoponini. Anterior
tergosternal fusion has proceeded to the point where the

Adetomyrma, a new ant genus from Madagascar 171

original suture has been lost. This is also seen in some
Amblyoponini, e.g. Mystrium, whereas in most members
of the tribe the tergosternal suture is still visible. The
posterior section of sternum 2 in Adetomyrma is triangular
in shape, adorned with an anteroventral tooth (with a
notched anterior margin in lateral view), and flanked by
a laterotergite. There is, however, no peduncular collar on
the petiolar tergum.

7.  The Adetomyrma worker is eyeless, in conformity
with the reduction/loss of eyes seen in Amblyoponini. Of
course this condition has evolved repeatedly in other ants.
A determination of whether the eyes are/were placed in
a posterior position on the head will probably have to
await the discovery of the queen caste.

8.   Less importantly, Adetomyrma has simple tarsal
claws and lacks a stridulatory file on abdominal tergum 4.
Because of homoplasy and polarity uncertainty, these two
characters cannot be given much weight. Other features
of uncertain significance (but possibly apomorphic) that
Adetomyrma shares with Amblyoponini include the head
shape (subquadrate, slightly converging posteriorly,
lacking posterolateral lobes), subfalcate mandibles, dor-
sally flattened and laterally rounded mesosoma, conspicuous
metapleural gland bulla, somewhat enlarged apical seg-
ment of the metatarsus, large curved metatibial spur, and
close association between the helcial and petiolar sternites.
Whereas any one of these features does not provide strong
evidence of a relationship to the Amblyoponini, together
they contribute to a close overall resemblance.

Adetomyrma also agrees with most of the remaining,
putatively plesiomorphic traits of the Amblyoponini
(except that abdominal segments 3 and 4 are unfused:
see below). Finally, in contrast to its evident similarities
to Amblyoponini, Adetomyrma does not share a suite
of derived characters with any other poneroid tribe or
subfamily. That the similarities between Adetomyrma and
Amblyoponini are due to convergence or to symple-
siomorphy must be admitted as logical possibilities, but
the totality of evidence weighs heavily against them. The
convergence hypothesis requires an excessive amount of
special pleading; and the hypothesis of symplesiomorphous
similarity would imply that generalized ponerines, with
large eyes, open metacoxal cavities and unfused petioles
(e.g. Rhytidoponera) arose from a clade of small-eyed,
hypogeic ants with reduced mouthparts, encircled meta-
coxal cavities and anterior tergosternal fusion of the petiole.
The conclusion seems inescapable that Adetomyrma is
a specialized amblyoponine, perhaps the sole survivor of
an early basal lineage in the tribe.

This further boosts the known representation of the
tribe Amblyoponini in the Malagasy region. In addition
to Adetomyrma Madagascar hosts six of the eight nom-
inal species of Mystrium (Brown, 1960), at least three
Amblyopone species (all undescribed) and at least five
species (mostly undescribed) of Prionopelta.

172 Philip S. Ward

Phylogenetic implications

If we accept that Adetomyrma is a cladistic member of the
tribe Amblyoponini - and the evidence points overwhelm-
ingly in this direction - then a paradox arises: Adetomyrma
lacks the derived traits that characterize the higher taxa in
which Amblyoponini is nested. The case is similar to that
of Mononykus, a primitive but wingless fossil bird (Norell
et al., 1993). If this creature was primitively flightless, then
this implies at least two origins of flight in birds, because
Mononykus postdates Archaeopteryx and has certain
bird-like features not possessed by the latter. Similarly, if
Adetomyrma has primitively unfused abdominal seg-
ments 3 and 4 this implies homoplasy (multiple origins)
of the apparent synapomorphies of the Ponerinae and the
'poneroid group'. Alternatively, one could postulate that
Adetomyrma has undergone secondary loss of the fusion
characters, i.e. reversal back to an unfused state, although
one might not expect these kinds of fusions to be revers-
ible. Which of these two alternatives is chosen has important
implications for the evolution of abdominal morphology in
ants and for the historical validity of both the Ponerinae
and the poneroid group. Below I consider these two poss-
ibilities, the evidence for each, and their implications.

1. Adetomyrma primitively lacks the abdominal fusion
characteristic of the Ponerinae and the poneroid group.
This would be consistent with the expectation, from com-
parative insect morphology, that fusion of major sclerites
is (typically) an irreversible evolutionary step. Moreover,
up to now there has been no evidence that the worker
caste of any ant has undergone a reversal of tergosternal
fusion of abdominal segment 3 (within the poneroid group)
or abdominal segment 4 (within the Ponerinae). Even the
enormously physogastric queens of army ants (within the
doryline section of the poneroid group) have retained
fusion of abdominal segment 3; and the dichthadiiform
queens of Onychomyrmex have also not been able to
break free from the constraints of fused abdominal seg-
ments 3 and 4. In addition, fusion would seem to be an
uncommon event: abdominal segment 3 is unfused, except
for the helcium, in all ants outside the poneroid group;
segment 4 is unfused in all ants except the Ponerinae.
Hence, until the discovery of Adetomyrma, these two
characters appeared to have the admirable qualities of
being unique and unreversed.

But if Adetomyrma, an amblyoponine, has primitively
loose abdominal segments, one must presume that fusion
of segments 3 and 4 (and the differentiation of presclerites
on the latter) in the Amblyoponini occurred independently
of that seen in other poneroids. That these are homo-
plasious characters is also suggested by a consideration of
male morphology. The males of some Amblyopone lack
complete fusion of abdominal segment 4 (Ward, unpubl.)
and, within the poneroid group, male Ecitoninae have the
postsclerites of abdominal segment 3 unfused (Bolton,
1990b). Thus male morphology already points to multiple
fusions; Adetomyrma simply extends the argument to the
worker caste. Unfortunately this means that the two taxa,
poneroid group and Ponerinae, are robbed of their key

synapomorphies. No derived character links Amblyoponini
to the other ponerine tribes, and the possibility of a closer
relationship to Apomyrminae, Leptanillinae or the dory-
line section cannot be discounted. The poneroid group
would remain tenuously defined by the (not unique) fusion
of the presclerites of abdominal segment 3, i.e. the helcial
sclerites. Fusion of the postsclerites of this segment must
be presumed to have occurred more than once in the
group.

2. Adetomyrma has undergone reversal with respect
to abdominal segment fusion. Leaving aside arguments
about the plausibility of reversal, this is certainly the most
parsimonious explanation when considering only a simple
count of the number of character state changes involved.
A plausibility argument might go something like the follow-
ing. The loosening of the abdominal segments, perhaps as
a result of combined selection pressures on the workers
and on the queen (as yet unknown but predicted to be
dichthadiiform), was possible because Adetomyrma be-
longs to an early ponerine line in which tergosternal fusion
of segments 3 and 4 had not proceeded to the point of
irreversibility. That fusion has not been stabilized in the
tribe Amblyoponini is indicated by the fact that in some
workers one can still discern the overlapping ends of the
plates of segment 4, i.e. posteriorly the tergum can be
seen to form a small, free overhang (especially marked in
Myopopone). One could also interpret the afore-mentioned
Amblyopone males, with their incomplete posterior fu-
sion, as exhibiting the same phenomenon. In the 'higher'
Ponerinae the fused plates tend not to have free overlap
posteriorly; and in the more derived members of the
doryline section (e.g. Dorylus) fusion of abdominal seg-
ment 3 has proceeded to the point where only a faint
suture line remains to mark the boundary between the
plates.

Adherence to this reversal scenario salvages the fusion
apomorphies of the poneroid group and the Ponerinae,
but they require somewhat awkward qualifications.

Prospects

At this point there is insufficent information to choose
between the two scenarios outlined above. Some com-
bination of the two might apply, for example, a fused third
abdominal segment and differentiated presclerites on
segment 4 might have been secondarily lost in Adetomyrma
even if the fourth abdominal segment is primitively un-
fused. A thorough character analysis of the poneroid taxa,
using tribes and genera as terminal units, will be necessary
for resolution of this problem. Discovery of the male and
queen castes of Adetomyrma could be expected to reveal
information of phylogenetic importance. If. for example,
the Adetomyrma male proves to have abdominal segments
3 and 4 fused this would strongly suggest reversal of fusion
in the worker.

There are broader implications to emerge from this
analysis of Adetomyrma. Regardless of whether this ant
exhibits primary or secondary lack of tergosternal fusion,

Adetomyrma, a new ant genus from Madagascar 173

Fig. 45. A conservative hypothesis of formicid relationships (extant subfamilies only), based on the assumption that tergosternal fusion of
abdominal segments is reversible. Closed bars: unique and unreversed characters; hatched bars: unique and reversed characters; open
bars: homoplasious characters with multiple origins (most of these are unique at the groundplan levels considered here but have also
originated within other lower taxa). The characters, worker- and queen-based unless otherwise noted, are as follows: (1) dorsal cuticular
flap of metapleural gland reduced anteriorly and extended posteromesally, so that metapleural gland orifice is directed more posteriorly
than laterally (guard hairs usually common); (2) all castes: metacoxal cavities closed by a thin strip of cuticle (condition in Aneuretus
uncertain); (3) reduction/loss of furcula of sting apparatus; (4) proventriculus sclerotized: (5) metabasitarsal sulcus (Ward, 1990) present
(this presumes a convergent origin in Paraponera): (6) sensilla basiconica of antenna with socket raised above the cuticular surface: this
condition, reported in Pseudomyrmecinae and Myrmecia (Hashimoto. 1991a), also occurs in Nothomyrmecia (present study); (7) labial
palpi with sparse covering of setiform sensilla (Hashimoto, 1991a); (8) all castes: fusion of helcial sclerites (convergently developed within
the formicoid group); (9) fusion of postsclerites of abdomen 3 (reversed in Adetomyrma); ( 10) metapleural gland orifice directed laterally,
close to the ventral margin of metapleuron; flanked dorsally by a well-developed cuticular flap and ventrally by a small plate or
prominence, these two being recessed medially at their posterior juncture, so that in posterior view the orifice is visible as a semicircular or
slit-shaped invagination; (11) metacoxal cavities broadly closed (convergently developed within other groups); (12) worker metatibial
gland (Bolton. 1990b) present: (13) helical sternite protruding mesoventrally below the level of the lateral arms of the helcial tergite;
(14) abdominal spiracles 5-7 exposed under normal gastral expansion: (15) worker pygidium spinose (some reduction occurs): (16) male:
hypopygium bifurcate; (17) metapleural gland orifice well separated from ventral metapleural margin, opening laterodorsally (posterior
exposure variable), in a depression above a protuberance or swelling of the posterolateral extremity of the metapleuron (this swelling
appears to be part of the bulla so that the orifice originates not below the bulla but in its lower quarter); guard hairs originating from the
lower margin of the protuberance or swelling; ( 18) tergosternal fusion of abdomen 4 (reversed in Adetomyrma); ( 19) dorsal stridulitrum on
abdominal pretergite 4 (convergently developed in Pseudomyrmecinae): (20) anterior clypeal margin with specialized, dentiform setae:
(21) metapleural gland orifice directed posterodorsally, visible as a crescentic slit-shaped cavity in posterior view: no guard hairs arising
from the posterolateral swelling; (22) anterior tergosternal fusion of petiole; free posterior portion of sternite with characteristic
configuration (see text); (23) anterior face of petiolar node steep and broad, dorsal face flat and extending to the posterodorsal margin
without descending into a distinct posterior face; (24) worker: compound eyes reduced/lost. Characters 17, 18, 20—23 must be presumed
reversed or otherwise modified if the Apomyrminae. Leptanillinae and Myrmicinae are positioned where indicated.

174 Philip S. Ward

it becomes increasingly difficult to justify the monophyly of
the Ponerinae (see also Hashimoto, 1991a). This is obvi-
ously the case if lack of fusion is primitive: the Ponerinae
lose their only synapomorphy. But even if Adetomyrma
has undergone reversal to an unfused state, this opens the
possibility that other taxa currently placed outside the
Ponerinae, such as Apomyrma, have undergone the same
kind of change. Recent studies (Ward, 1990; Bolton,
1990b; Baroni Urbani et al., 1992) have rejected the notion
(expressed in Brown (1954), Wilson (1971) and Taylor
(1978), among others) of a close relationship between
Myrmicinae and Ponerinae, on the grounds that the
Myrmicinae lack tergosternal fusion of abdominal seg-
ments 3 and 4. But if fusion reversal can occur—or if there
have been multiple fusions - this argument loses much of
its force. There are intriguing, potentially apomorphic,
similarities between the Ectatommini (excluding Para-
ponera) and the Myrmicinae, in the configuration of the
metapleural gland orifice and the morphology of the
propodeal foramen (Figs 28, 29, 34, 35), and in antennal
sensillum characters (Hashimoto, 1991a). The Pseudo-
myrmecinae, said to be a sister group of the Myrmicinae
(Ward, 1990; Baroni Urbani et al., 1992), do not share
these features, casting doubt on their affinities with the
Myrmicinae. Fig. 45 summarizes the relationships among
the major ant groups that are suggested by the present
study, under the assumption that tergosternal fusion
is reversible. The support for some of these groupings
remains weak, and if Adetomyrma has a primitively loose
gaster then further uncertainty is introduced.

Finally, Adetomyrma rekindles the debate about whether
the broad attachment between abdominal segments 2 and
3, as seen in Amblyoponini, is primitive or derived (for
a succinct explanation of the problem and its ramifications
for ant evolution see Wilson, 1971: 31). This puzzling
poneroid from Madagascar certainly undermines any
complacency about established views on ant phytogeny.

Acknowledgments

My thanks to Barry Bolton, Bill Brown and Stefan Cover
for comments, loans of material, and other help. Gary
Alpert, Pascal Rabeson and Emile Rajeriarison were
stalwart companions during field work in Madagascar. For
other logistical assistance in Madagascar I am grateful to
Steve Goodman, Claire Kremen (Xerces Society), Vincent
Razafimahatratra, and the Ministère des Universités. This
study was supported by NSF BSR-9006393.

References

Arnett, R.H., Jr, Samuelson, G.A. & Nishida, G.M. (1993) The

Insect and Spider Collections of the World, 2nd edn. Sandhill

Crane Press, Gainesville.
Baroni Urbani, C, Bolton, B. & Ward, P. S. (1992) The internal

phytogeny of ants (Hymenoptera: Formicidae). Systematic

Entomology. 17, 301-329.

Battistini, R. & Richard-Vindard, G. (eds) (1972) Biogeography

and Ecology of Madagascar. Junk, The Hague.
Bolton, B. (1979) The ant tribe Tetramoriini (Hymenoptera:

Formicidae). The genus Tetramorium Mayr in the Malagasy

region and in the New World. Bulletin of the British Museum

{Natural History) (Entomology), 38, 129-181.
Bolton, B. (1981) A revision of six minor genera of Myrmicinae

(Hymenoptera: Formicidae) in the Ethiopian zoogeographical

region. Bulletin of the British Museum (Natural History) (Ento-
mology), 43, 245-307.
Bolton. B. (1990a) The higher classification of the ant subfamily

Leptanillinae (Hymenoptera: Formicidae). Systematic Ento-
mology), 15, 267-282.
Bolton, B. (1990b) Army ants reassessed: the phylogeny and

classification of the doryline section (Hymenoptera: Formicidae).

Journal of Natural History, 24, 1339-1364.
Bolton, B. (1994) Identification Guide to Ant Genera of the World.

Harvard University Press, Cambridge, Mass.
Brown, W.L., Jr (1954) Remarks on the internal phylogeny

and subfamily classification of the family Formicidae. Insectes

Sociaux, 1, 21—31.
Brown, W.L., Jr (1960) Contributions towards a reclassification

of the Formicidae. III. Tribe Amblyoponini (Hymenoptera).

Bulletin of the Museum of Comparative Zoology, 122, 143-230.
Brown, W.L., Jr (1965) Contributions towards a reclassification

of the Formicidae. III. Tribe Typhlomyrmecini (Hymenoptera).

Psyche, 72, 65-78.
Brown, W.L., Jr (1974a) Concoctio genus nov. Pilot Register of

Zoology Card No. 29.
Brown. W.L., Jr (1974b) Concoctio concenta species nov. Pilot

Register of Zoology Card No. 30.
Brown, W.L., Jr (1975) Contributions towards a reclassification

of the Formicidae. V. Ponerinae, tribes Platythyreini, Cerapa-

chyini, Cylindromyrmecini, Acanthostichini, and Aenictogitini.

Search, Agriculture, 5, 1-115.
Brown, W.L., Jr (1978) An aberrant new genus of myrmicine ant

from Madagascar. Psyche, 84, 218-224.
Brown, WL., Jr, Gotwald, W.H., Jr & Lévieux. J. (1971) A

new genus of ponerine ants from West Africa (Hymenoptera

Formicidae) with ecological notes. Psyche. 77, 259—275.
Forel. A. (1891) Histoire naturelle des Hyménoptères. Deuxième

partie. Les formicides. In: Grandidier, A. Histoire physique.

naturelle, et politique de Madagascar. Vol. 20(2). Paris: Impr.

Nationale, v + 237pp.
Forel, A. (1893) Sur la classification de la famille des formicides.

avec remarques synonymiques. Annales de la Société Ento-
mologique de Belgique, 37. 161-167.
Gotwald. W.H. (1982) Army ants. Social Insects (ed. by H. R.

Hermann). Volume 4, pp. 157-254. Academic Press, New

York.
Gotwald. W.H.. Jr & Lévieux, J. (1972) Taxonomy and biology

of a new West African ant belonging to the genus Amblyopone

(Hymenoptera: Formicidae). Annals of the Entomological

Society of America, 65, 383—396.
Hashimoto, Y. (1991a) Phylogenetic study of the family Formicidae

based on sensillum structures on the antennae and labial palpi

(Hymenoptera, Aculeata). Japanese Journal of Entomology.

59.125-140.
Hashimoto, Y. (1991b) Phylogenetic implications of the spur

structures of the hind tibia in the Formicidae (Hymenoptera).

Japanese Journal of Entomology, 59. 289-294.
Hölldobler, B. & Palmer. J.M. (1989) A new tarsal gland in ants

and the possible role in chemical communication. Naturwissen-

schaften, 76, 385-386.
Hölldobler. B. & Wilson, E.O. (1986) Ecology and behavior of

the primitive cryptobiotic ant Prionopelta amabilis (Hymen-
optera: Formicidae). Insectes Sociaux, 33. 45-58.

Hölldobler, B. & Wilson, E.O. (1990) The Ants. Harvard Univer-
sity Press, Cambridge, Mass.

Ito, F. (1993) Observation of group recruitment to prey in a
primitive ponerine ant. Amblyopone sp. (reclinata group)
(Hymenoptera: Formicidae). Insectes Sociaux, 40, 163—167.

Jolly, A., Oberlé, P. & Albignac, R. (1984) Key Environments:
Madagascar. Pergamon Press, Oxford.

Kugler, C. (1978) A comparative study of the myrmicine sting
apparatus (Hymenoptera: Formicidae). Studia Entomologica,
20, 413-548.

Kugler, C. (1980) The sting apparatus in the primitive ants
Nothomymecia and Myrmecia. Journal of the Australian Ento-
mological Society, 19, 263-267.

Kugler, C. (1991) Stings of ants of the tribe Ectatommini (Formi-
cidae: Ponerinae). Insecta Mundi, 5, 153—166.

Kugler, C. (1992) Stings of ants of the Leptanillinae (Hymen-
optera: Formicidae). Psyche, 99, 103-115.

Martin, R.D. (1990) Primate Origins and Evolution. Chapman
and Hall, London.

Masuko, K. (1986) Larval hemolymph feeding: a nondestructive
parental cannibalism in the primitive ant Amblyopone silvestrii
Wheeler (Hymenoptera: Formicidae). Behavioral Ecology
and Sociobiology, 19, 249-255.

Masuko, K. (1990) Behavior and ecology of the enigmatic ant
Leptanilla japonica Baroni Urbani (Hymenoptera: Formicidae:
Leptanillinae). Insectes Sociaux, 37, 31—57.

Norrell, M., Chiappe, L. & Clark, J. (1993) New limb on the
avian family tree. Natural History, 102 (9), 38-42.

Olson, D.M. & Ward, P.S. (1994) The ant fauna of Kirindy

Adetomyrma, a new ant genus from Madagascar 175

Forest (tropical dry forest) in western Madagascar. In: The
Ecology and Economy of a Tropical Dry Forest (ed. by
J. Ganzhorn). Springer, Berlin.

Rabinowitz, P.D., Coffin, M.F. & Flavey, D. (1983) The separ-
ation of Africa and Madagascar. Science, 220, 67—69.

Stiassny, M.L.J. (1992) Phylogenetic analysis and the role of
systematics in the biodiversity crisis. Systematics, Ecology, and
the Biodiversity Crisis (ed. by N. Eldredge), pp. 109-120.
Columbia University Press, New York.

Tattersall, I. (1982) The Primates of Madagascar. Columbia
University Press, New York.

Taylor, R.W. (1978) Nothomyrmecia macrops: a living-fossil ant
rediscovered. Science, 210, 979-985.

Ward, P.S. (1989) Systematic studies on pseudomyrmecine ants:
revision of the Pseudomyrmex oculatus and P. subtilissimus
species groups, with taxonomic comments on other species.
Quaestiones Entomologicae, 25, 393—468.

Ward, P.S. ( 1990) The ant subfamily Pseudomyrmecinae (Hymen-
optera: Formicidae): generic revision and relationship to other
formicids. Systematic Entomology, 15, 449—489.

Wheeler, G.C. & Wheeler, J. (1976) Ant larvae: review and
synthesis. Memoirs of the Entomological Society of Washington,
7, 1-108.

Wheeler, W.M. (1922) Ants of the American Museum Congo
expedition. A contribution to the myrmecology of Africa. IX.
A synonymic list of the ants of the Malagasy region. Bulletin of
the American Museum of Natural History, 45, 1005—1055.

Wilson, E.O. (1971) The Insect Societies. Harvard University
Press, Cambridge, Mass.

Accepted 2 March 1994