Workers (
Small species (
The Thai specimens agreed well with the holotype (
Thailand (Songkhla and Narathiwat, new record, Fig.
Two specimens from Narathiwat Province were collected from the ground in a disturbed area near a lowland evergreen forest, near the Thai–Malay border. A specimen (
Holotype worker:
Mandibles striate, shiny. Antennal scapes superficially striate. Head dorsally sparsely reticulate-rugulose laterally, while median portion weakly sculptured; half posterior portion of antennal scrobes shagreened mixed with few transverse ridges. Promesonotal shield more weakly sculptured than dorsum of head, with median portion smooth, shiny, and lacking any rugae; in profile, upper one-third portion of pronotum shagreened, while lower two-third portion with sparse irregular ridges; upper one-third portion of mesopleuron shagreened, lower two-thirds longitudinal weakly striate; metapleuron, and lateral faces of propodeum somewhat smooth and shiny. Propodeum declivity shagreened. Petiole smooth and shiny, postpetiole somewhat smooth but posterior face of postpetiole scabrous. First gastral tergite superficially shagreened with smooth and shiny interspaces.
Dorsa of head and mesosoma with dense erect hairs mixed with sparse longer hairs; antennae with dense suberect hairs; in profile, lower two-thirds of pronotum with sparse suberect hairs; lower one-third of mesopleuron and metapleuron with sparse suberect hairs; area around propodeal spiracle with sparse suberect hairs; femora and tibiae with numerous long outstanding hairs as well; petiole with weakly sparse erect hairs on its anterior face and dorsum; postpetiole with dense long erect hairs, except anterior face without hairs; gaster with dense long erect hairs. Body mainly reddish brown; mandibles, antennae, legs, and tip of gaster yellowish brown.
Thailand (Uthai Thani, Chonburi, Nakhon Ratchasima and Kanchanaburi Provinces, Fig.
The specific name is after Thailand where the type locality is located; Thailand was called “Siam” in the past.
This species can be found in dry evergreen and dry dipterocarp forests. The specimens collected from northeastern Thailand (colony code TH22-WJT-264) nested in the soil. Workers moved slowly on the ground.
The type series of
Holotype worker:
Mandibles striate but shiny. Antennal scapes superficially striate. Dorsum of head in full-face view entirely reticulate; posterior half of antennal scrobes shagreened mixed with a few transverse ridges. Dorsum of promesonotal shield distinctly reticulate but median region with weaker reticulation than elsewhere; in profile, upper half portion of lateral faces of pronotum shagreened, while lower half portion with sparse irregular ridges; upper one-third portion of mesopleuron shagreened, lower two-third portion weakly longitudinally striate; metapleuron and lateral face of propodeum smooth and shiny. Propodeum declivity superficially shagreened. Petiole smooth and shiny. Postpetiole somewhat smooth but upper portion of posterior face with wrinkles. First gastral tergite superficially shagreened with smooth and shiny interspaces.
Dorsum of head with dense erect hairs (usually a closed cell with a hair), hairs along head margin clearly longer than hairs on middle of head; antennae with dense, suberect hairs; promesonotal shield with dense, erect hairs; legs with dense suberect hairs; in profile, lower two-thirds of pronotum with sparse suberect hairs; lower one-third of mesopleuron and metapleuron with sparse suberect hairs; area around propodeal spiracle with sparse, suberect hairs; femora and tibiae with numerous long, outstanding hairs as well; petiole with sparse, erect hairs on its dorsum; postpetiole with dense, long, erect hairs, except anterior face without hairs; femora and tibiae with numerous long, outstanding hairs as well; gaster with dense, long, erect hairs. Dorsum of body (head, mesosoma, and gaster) and waist yellowish brown; mandibles, antennae, legs, and tip of gaster yellow.
Laos (Vientiane Province), Thailand (Kalasin and Mukdahan Provinces, Fig.
Distribution of
The specific name is dedicated to Professor Alongklod Tanomtong of Khon Kaen University, who is an excellent specialist in biological sciences in Thailand, who helped and inspired many young biologists.
This species can be found in lowland primary forest (300–600 m a.s.l.). The type series was collected from a dry dipterocarp forest. Lao specimens (colony code WJT10-LAO111) were collected from a dry evergreen forest. Specimens from Mukdahan Province, northeastern Thailand were collected in a mixed deciduous forest.
Characters used in key
Characters used in key
| 1 | Postpetiole in profile subquadrate (Fig. |
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| – | Postpetiole in profile nodiform and convex dorsal outline (Figs |
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| 2 | In full-face view, anterior corners of frontal lobes round and lateral margin weakly convex (Fig. |
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| – | In full-face view, anterior corners of frontal lobes right angled and lateral margin almost straight (Fig. |
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| 3 | Petiolar crest distinctly bidentate; postpetiole with an acute, posteriorly directed short spine (Fig. |
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| – | Petiolar crest never bidentate; postpetiole without an acute, posteriorly directed short spine (Figs |
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| 4 | Propodeum never overhung by posterior mesonotal margin (Fig. |
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| – | Propodeum slightly overhung by posterior translucent margin of promesonotal shield (Fig. |
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| 5 | Propodeum never overhung by the posterior mesonotal margin (Fig. |
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| – | Propodeum overhung by the posterior mesonotal margin (Fig. |
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| 6 | Mandibles with five teeth; dorsal surface of head and promesonotum smooth, additionally distinctly carinulate (Fig. |
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| – | Mandibles with four teeth; dorsal surfaces of head and promesonotam with reticulations (Fig. |
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| 7 | Promesonotal shield armed with a very long, acute spine at each corner (Fig. |
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| – | Promesonotal shield without or with different armament, never with such long spines at the corners of the promesonotal shield (Fig. |
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| 8 | Promesonotal shield rectangular, lacking any armament (Fig. |
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| – | Promesonotal shield always with conspicuous, specific outstanding projections (Fig. |
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| 9 | In profile, petiole distinctly obliquely truncate (Fig. |
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| – | In profile, petiolar crest only narrowly truncate (Fig. |
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| 10 | Promesonotum with only one pair of posteriorly directed mesonotal spines, without additional posterolateral and/or posterior paramedian mesonotal projections (Fig. |
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| – | Promesonotum of different shape, always with additional posterolateral and/or posterior paramedian mesonotal projections (Fig. |
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| 11 | Small species ( |
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| – | Larger species ( |
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| 12 | Dorsal surfaces of head and promesonotal shield rugose to rugulose-reticulate (Fig. |
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| – | Dorsal surfaces of head and promesonotal shield shiny, with rugae and costulae (Fig. |
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| 13 | Outline of lateral margins of promesonotum convex in dorsal view, each margin with two large translucent fenestrae; promesonotal shield conspicuously shorter than broad, foliaceous ( |
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| – | Outline of lateral margins of promesonotum in dorsal view not convex, with lateral constrictions; margins never provided with four translucent fenestrae of that size; promesonotal shield usually longer than broad ( |
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| 14 | Mesosoma in dorsal view rectangular; lateral margins parallel-sided with a weak constriction at the level of lateral fenestrae (Fig. |
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| – | Mesosoma in dorsal view not rectangular, lateral margins never parallel-sided, conspicuously narrowed towards posterior margin, with distinct lateral constrictions at the level of lateral fenestrae (Fig. |
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| 15 | Posterior margin of mesonotum sinuate, with blunt rounded projections, lacking distinct spines (Fig. |
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| – | Posterior margin of mesonotum with distinct acute paramedian spines (Fig. |
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| 16 | First gastral tergite smooth and shining; body bright yellowish orange (Fig. |
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| – | First gastral tergite entirely shagreened, anteriorly sometimes with a faint, minute reticulum; body dark brown (Fig. |
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| 17 | Petiole in profile distinctly truncate dorsally (Fig. |
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| – | Petiole in profile cuneate dorsally (Fig. |
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| 18 | In dorsal view, promesonotal shield with distinct spine-like posterolateral and posterior projections (Fig. |
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| – | In dorsal view, promesonotal shield with spine-like projections only posteriorly (Fig. |
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Characters used in key
Characters used in key
Characters used in key