Taxonomy. The genus Aphaenogaster is assigned to the tribe Pheidolini (Bolton 2003). Workers of Vietnamese species have the following features.

 

Worker monomorphic; head in full-face view oval or elliptical, often with extremely elongate neck; frontal carina, if distinct, not extending beyond the level of eye in full-face view; antennal scrobe absent; parafrontal ridge or carina(e) often present; median portion of clypeus convex anteriad, sometimes with a shallow emargination at midpoint; posteromedian portion of clypeus moderately or relatively broadly inserted between frontal lobes; masticatory margin with apical and 2 distinct preapical teeth followed by several smaller teeth or denticles; palp formula 5,3 or 4,3; antenna 12-segmented, gradually incrassate toward apex or with an indistinct 4-segmented club; eye medium sized; mesosoma elongate; promesonotum forming a dome; promesonotal suture weakly present or absent dorsally; metanotal groove moderately or strongly impressed dorsally; propodeal spines varying in size and shape (rarely reduced to tiny denticles or rounded angles); propodeal lobe round or subtriangular with blunt angles; petiole consisting of an anterior peduncle and a node (separation between peduncle and node sometimes indistinct); gastral shoulder absent.

 

The worker of Aphaenogaster is similar to the minor worker of Pheidole (larger species) and the worker of Kartidris and Myrmica . In the minor worker of Pheidole the masticatory margin of the mandible bears 1 or 2 small teeth between the preapical tooth and the 3rd large tooth. In the worker of Kartidris the vertex has a broad depressed area between eyes, the masticatory margin of the mandible has 5 distinct teeth, the antennal club is distinctly 3-segmented, and the propodeum is unarmed. In the worker of Myrmica the promesonotum is only slightly raised and the propodeal lobe is well-developed as a triangular or sharp lamella. In addition, the palp formula is always 6,4 in Myrmica as opposed to 5,3 or 4,3 in Aphaenogaster .

 

Vietnamese species. Twelve species have been recognized by us from Vietnam: exasperata Wheeler [= sp. eg- 22] (Ba Be, Cuc Phuong, Pu Mat, Tay Yen Tu, Van Ban); sp. eg-1 (Sa Pa); sp. eg-2 (Sa Pa); sp. eg-3 (Sa Pa); sp. eg-4 (Sa Pa); sp. eg-6 [= sp. eg-15 in Eguchi et al. 2005] (Ba Vi, Sa Pa); sp. eg-10 (Phu Quoc); sp. eg-17 [= sp. 25 of SKY in Yamane et al. 2003] (Cuc Phuong, Ky Thuong, Pu Mat, Tay Yen Tu); sp. eg-18 [= sp. 22 of SKY in Yamane et al. 2003; = sp. eg-6 and sp. eg-15 in Eguchi et al. 2005] (Ba Vi, Cuc Phuong, Pu Mat, Tam Dao, Tay Yen Tu); sp. eg-21 (Tam Dao); sp. eg-25 (Nui Chua); sp. eg-26 (Van Ban).

 

Bionomics. The majority of species inhabit well-developed forests but some occur in sparse forests, dwarf forests and areas with low bushes. Nests are usually found in the soil, under stones and in rotting logs (Bui & Eguchi 2003, Eguchi et al. 2004).

Of the six species of this genus occurring in California, one ( A. occidentalis (Emery)) is widespread in mesic habitats, four are confined to deserts, and one species ( A. patruelis Forel ) is endemic to the Channel Islands and Isla Guadalupe. All are ground-nesting ants, with somewhat generalized scavenging habits.

 

Species identification: keys in Creighton (1950a), Wheeler and Wheeler (1986g) and Mackay and Mackay (2002). Additional references: Creighton (1955), De Andrade (1995), Hölldobler and Carlin (1990), Hölldobler et al. (1995), Johnson (2000a, 2001), Jones and Phillips (1989), Sanders and Gordon (2002), Schulz (1994), Smith (1963c), Umphrey (1996), Wheeler and Creighton (1934).

Aphaenogaster Mayr , 1853: Verh. zool.-Bot. Ges. Wien. 3:101-114.

 

Distribution: Palaearctic, Ethiopian (Madagascar only), Oriental, Australian, Nearctic & Neotropical regions.

 

Key to species

 

1- Head very slender, nearly twice as long as broad, with faint longitudinal sculptures on anterior half, propodeum armed with two blunt tubercles (Fig.28) .................................. ... Aphaenogaster phillipsi Wheeler & Mann

 

- Head normal, nearly as long as broad, with, strong sculptures; propodeum armed with two acute spines (Fig.29) ............................. ................. Aphaenogaster syriacum Emery

Diagnosis. Antennae 12 segmented (including the scape) with a 4 segmented club (Fig. 9). In side view the propodeum depressed below the level of the pronotum and anterior region of the mesonotum, these two regions being connected by the steeply sloping posterior section of the mesonotum (Fig. 2). Monomorphic.

 

Aphaenogaster is most likely to be confused with Pheidole or possibly Pheidologeton . Workers of Aphaenogaster can be separated from those of Pheidole by the 4 segmented rather than 3 segmented club and the larger body size (over 3.4mm long), and from Pheidologeton by the 12 segmented antennae (11 segmented in Pheidologeton ). Additionally, both Pheidole and Pheidologeton have polymorphic workers while Aphaenogaster is monomorphic.

 

The Australian species of Aphaenogaster show differences which are little more than "variation on a theme." This is in contrast to the nearby Papua New Guinea fauna where morphological variation is considerable(Smith 1961). This difference suggests that the Australian fauna is composed of closely related species while that of PNG consists of several more distantly related lineages.

 

List of Australian species

 

barbarasp. n. (Queensland)

 

barbigula Wheeler (New South Wales, Queensland, South Australia, Victoria)

 

kimberleyensissp. n. (northern Northern Territory, northern Western Australia)

 

longiceps (Smith) (ACT, New South Wales, southern Queensland, south-east South Australia, Victoria)

 

flava Emery (new synonymy)

 

ruginota Forel

 

mediterraesp. n. (western South Australia, southern Western Australia)

 

poultoni Crawley (south-western Western Australia)

 

pythia Forel (Queensland, PNG)

 

reichelaesp. n. (northern Northern Territory)

 

Key to species of Australian Aphaenogaster based on workers

 

1. Majority of hairs on venter of head located laterally and forming a distinct psammophore, only scattered hairs on central portion (Fig. 4) ................................................................................................................... 2

 

- Hairs on venter of head randomly distributed and not forming a distinct psammophore (Fig. 2)..............4

 

2 Eye relatively large (EI greater than 21, Fig. 19); scape relatively long (SI greater than 106, Fig. 20)........ ...................................................................................................................................................... mediterrae

 

- Eye relatively small (EI less than 21, Fig. 19); scape relatively short (SI less than 106, Fig. 20)..............3

 

3. Petiolar node (in dorsal view) wider than long; mandibular sculpture composed of irregularly sized striations(Fig. 6) (occurring in Western Australia)................................................................................. poultoni

 

- Petiolar node (in dorsal view) approximately square; mandibular sculpture composed of regularly sized striations (Fig. 5) (occurring in South Australia and eastward)...................................................... barbigula

 

4. Posterior margin of head nearly flat in full face view, extending laterally of the occipital collar before passing through a distinct posterolateral corner into the lateral margin of the head (Fig. 15).................... 5

 

- Posterior margin of head broadly arched in full face view, the arch beginning at the occipital collar and with at most a weak angle separating the posterior and lateral margins of the head (often posterior and lateral margins forming a continuous surface) (Fig. 9) ................................................................................... 6

 

5. Scape relatively short (SI less than 125, Fig. 23) (occurring in e. Queensland and ne. New South Wales) ............................................................................................................................................................. pythia

 

- Scape relatively long (SI greater than 135, Fig. 23) (occurring in Northern Territory) .................. reichelae

 

6. Shorter erect hairs on mesosomal dorsum (especially those on mesonotum) with blunt tips; dorsal surfaces of propodeum and propodeal spines connected through a gentle concavity (so that the base of each spine is at approximately the same level as the dorsal surface of the propodeum) (Fig. 10).................. longiceps

 

- Erect hairs on mesosomal dorsum tapering to sharp points; dorsal surfaces of propodeum and propodeal spines connected through a gentle concavity followed by a gentle convexity (so that the base of each spine is raised slightly above the dorsal surface of the propodeum) (Fig. 8)........................................................7

 

7. Head relatively narrow (Fig. 21), scape relatively long (Fig. 22) (occurring in n. Northern Territory and n. Western Australia).................................................................................................................. kimberleyensis

 

- Head relatively broad (Fig. 21), scape relatively short (Fig. 22) (occurring in Queensland)........... barbara

[[worker]] [[queen] [[male]]. Kopf nicht halsförmigverlängert . Vorderflügelgewöhnlich mit 2 geschlossenen Cubitalzellen.

 

Holarktische Region, reicht bis in Hindostan.

[[worker]] Kein bedeutender Dimorphismus; Größe der [[worker]] in der Regel wenig veränderlich ; Kopf länger als breit. Clipeus in der Mitte seines Vorderrandes abgerundet oder auch seicht ausge-randet; Stirnleisten kurz; Stirnfeld eingedrückt . Mandibel vorgestreckt, am Außenrand nur mäßiggekrümmt , der Kaurand gezähnt . Antenne zwölfgliedrig , mit viergliedriger Clava, welche kürzer ist als der Rest des Funiculus. Thorax gestreckt, mit deutlicher Promesonotalsutur, Mesoepinotalnaht eingedrückt , Epinotum meist bewehrt; Petiolus vorn gestielt.

 

[[ queen]]. Kopfbildung und Stielchen wie bei der [[worker]]; Thorax gestreckt, meist mit stärkerenZähnen oder Dornen als bei der [[worker]] Vorderflügel mit 2 geschlossenen Cubitalzellen und mit Discoidal-zelle (bei dem Subgen. Ischnomyrmex und bei A. sagei ist nur eine Cubitalzelle geschlossen).

 

[[male]]. Clipeus wie bei der [[worker]]; Auge groß , manchmal sehr groß . Antenne 13 gliedrig, mit fünfgliedriger Clava; Scapus kürzer oder nicht länger als die folgenden 3 Glieder; erstes Glied des Funiculus nicht oder wenig geschwollen, nicht kugelig. Thorax ohne Mayr sehe Furchen; Epinotum hinten verlängert , sehr verschiedenartig gestaltet und für einzelne Arten sehr eigentümlich . Flügel wie im [[queen]].

 

Nester in der Erde; die meisten Arten leben von Raub und sind langbeinige, flinke Ameisen; andere leben mehr versteckt.

 

Die Gattung zerfällt in 2 Untergattungen, Ischnomyrmex und Aphaenogaster s. str.

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 0
Species: 37
Species With Barcodes: 1

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 0
Species: 1
Species With Barcodes: 1

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 0
Species: 1
Species With Barcodes: 1

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 0
Species: 2
Species With Barcodes: 1

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 0
Species: 1
Species With Barcodes: 1

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 0
Species: 2
Species With Barcodes: 1

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 0
Species: 11
Species With Barcodes: 1

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 0
Species: 11
Species With Barcodes: 1