Pheidole plagiaria F. Smith
Creators: name: Eguchi, K.
Publisher: name: Zenodo
Year: 2008
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Formicidae
Pheidole
Pheidole plagiaria

description: Pheidole plagiaria F. Smith
Figs. 20a-g, 32e, 32f
Pheidole plagiaria F. Smith, 1860: 112. Eguchi, Bui et al. 2005: 90 (checklist). Syntypes: 3 majors & 3 minors, "Bac" [Batjan, Indonesia], OXUM TYPE HYM: 983 1-2/6, 3-4/6 & 5-6/6, examined.
Pheidole divergens Mayr, 1867: 97. Mayr, 1879: 675 (junior synonym of P plagiaria). Syntypes: major, minor, queen & male, Indonesia, not examined.
Pheidole peguensis r. yomensis Forel, 1903: 253. Syn.n. Syntype: 1 major, "Lower Burma Pegu Yoma 1 1900 Bingham" [Myanmer], MHNG, examined, designated as lectotype [Fig. 32e, 32f].
Current subspecies (Bolton, 1995): nominal plus moica Forel, 1911c: 222, syntype(s): major, Central part of Southern Vietnam, not examined; palawanica Stitz, 1925: 118, syntypes: 2 majors, "N. Palawan Binaluan Boettcher" [Philippines], ZMHB, examined; rectilineata Viehmeyer, 1916b: 288-289, syntype(s): major, Sulawesi (in copal), not examined.
Other material examined: S. China: Hainan: Jianling N.R., Wanling [J. Fellowes]. Vietnam: Thai Nguyen: My Yen Commune Forest, 21°35'N, 135°36'E, Na Hau Village [Eg01-VN-147]; Vinh Phuc: Tam Dao N.P., 21°27'N, 105°38'E, 800-900 m alt. [Eg99-VN-037, -038], Tam Dao N.P., 900 m alt. [Eg99-VN- 001, -005, -008, -009; Eg01-VN-104, -106], Tam Dao N.P., 900-1100 m alt. [Eg99-VN-052], Tam Dao N.P., 1100 m alt. [VN98-SKY-14]; Ha Tay (mislabeled as "Ha Tai"): Ba Vi N.P., 400-800 m alt. [Eg99-VN-119]. Thailand: Chiang Mai: Doi Ang Khang HQ, 1300 m alt. [TH98-SKY-28], Doi Chiang Dao [Eg01-TH-122, - 134, -148], Doi Chiang Dao, 500-600 m alt. [TH98-SKY-18], Doi Suthep-Pui N.P., 600 m alt. [TH98-SKY- 04], Doi Suthep-Pui N.P., 800 m alt. [TH98-SKY-08], Doi Suthep-Pui N.P., 800-900 m alt. [Eg01-TH-069, - 096, -098, -100], Doi Suthep-Pui N.P., 900 m alt. [Eg01-TH-082, -083, -086, -087, -089, -090], Doi SuthepPui N.P., 1200 m alt. (Doi Pui) [Eg01-TH-110, -118]; Nakhonratchasima: Khao Yai N.P. [TH00-SKY-24], nr. Sakaerat Environmental Research Centre [Eg99-TH-020; Eg01-TH-532, -549]; Chanthabri: Khao Soi Dao [Eg01-TH-021]; Chacheongsao: Lumchangwat Station, Khao Ang Reu Nai W.S. [TH03-SKY-69]; Pattani: Soi Khao [TH98-SKY-40]; Trang: Khao Chong Waterfall [Eg01-TH-708, -714, -723, -736, -745, -746, -758]; Songkhla: Ton Nga Chang, nr. Hat Yai [Eg01-TH-613, -615, -626, -628], Songkhla Univ. (Khao Kor Hong) [Eg01-TH-597, -598]; Narathiwat: Bala area of Bala-Hala W.S. [Eg01-TH-636]. Myanmar: Chin: between Kampetlet and Natmataung N.P., 1670 m alt. [MM02-SKY-46], between Kampetlet and Natmataung N.P., 1700 m alt. [MM02-SKY-02], between Kampetlet and Natmataung N.P., 1760 m alt. [MM02-SKY-34], Natmataung N.P., 2000 m alt. [MM02-SKY-10], Natmataung N.P., 21°13'N, 93°56'E, 2000 m alt. [MM02-SKY- 24, -26, -29]. W. Malaysia: Selangor: Ulu Gombak [FI92MG-174, -383]. E. Malaysia: Sabah: Deramakot Forest Reserve [C. Briihl], Gunong Rara [Eg96-BOR-351, -363; Eg97-BOR-526, -534, -556, -566], Poring, 450- 500 m alt. [Eg96-BOR-271], Poring, 500-550 m alt. [Eg96-BOR-294], Poring, 600 m alt., [T. Kikuta's colony: 8-A, 43A, 731, 6XI2306S1-4], Sepilok Forest [Eg97-BOR-412, -418, -460, -464; Eg98-BOR-871], Tawau Hills Park [Sk. Yamane]; Sarawak: Lambir Hills N.P. [Eg98-BOR-803, -808, -817, -819, -825, -829], Lambir Hills N.P. (Inoue Trail) [SR04-SKY-67]. Brunei: Belalong Forest Section [Eg99-BOR-211], Merimbun Heritage Park (=Tasek Merimbun) [Eg99-BOR-007, -008, -028, -030, -035, -070, -074, -123, -150, -552, -567, -568; Eg00-BOR-019, -022, -064]. Indonesia: E. Kalimantan: Sangkimah, Kutai N.P. [Sk. Yamane]; W. Sumatra: Sukarami, nr. Padang [FI92-66, -83; FI96-162; M. Kawamura's colony: 9/29c (1999)]; Krakatau Is.: P. Rakata Besar [Kagoshima Univ. Krakatau Exp.]; W. Java: Cibodas [M. Kawamura's colony: D28 (1997)], Kebun Raya, Bogor [FI95-534, -784; Sk. Yamane; M. Kawamura's colony: 154 (1998), 9/26a (1999), 10/5b (1999), 10/5c (1999)], G. Halimun [FI98-373; M. Kawamura's colony: 5/6a (1998)], Pangandaran [FI95-705], Ciater, 1350 m alt. [Syaukani]; C. Java: Borobudur, nr. Yogyakarta [Sk. Yamane], Kaliadem, 800-1000 m alt., G. Merapi [JV02/03-SKY-38]; E. Java: Sumberbrantas, 1600 m alt., Tulungrejo, Batu [JV02/03-SKY-78, -79]; Bali: Kebun Raya [FI94-137]. Philippines: Leyte: Baybay, Mt. Pangasugan, Calbiga-a River [Zettel].
Worker measurement & indices: Major (n=5). - HL 1.65-1.89 mm, HW 1.59-1.77 mm, CI 91-98, SL 1.03-1.22 mm, SI 59-71, FL 1.42-1.70 mm, FI 85-99.
Minor (n=5). - HL 0.79-0.93 mm, HW 0.67-0.75 mm, CI 81-85, SL 1.01-1.20 mm, SI 146-163, FL 1.12-1.36 mm, FI 162-181.
Worker description
Major. - Head in lateral view not or only very weakly impressed on vertex; posterior margin of head in full-face view relatively widely and deeply concave; longitudinal rugulae running on the frons and then spreading posterolaterad as they run almost transversely on the posteriormost part of the dorsum of vertexal lobe; posterolateral face of head with oblique rugulae which run anteroventrad from dorsal face of vertexal lobe; frontal carina conspicuous; antennal scrobe inconspicuous or only weakly impressed; median longitudinal carina of clypeus present but weak, or rarely absent; median and submedian processes of hypostoma inconspicuous or absent; lateral processes conspicuous; outer surface of mandible covered with relatively long decumbent hairs; antenna with a 3-segmented club; maximal diameter of eye a little longer, as long as, or a little shorter than antennal segment X. Promesonotal dome in dorsal view transversely rugose with interspaces smooth to shagreened, or smooth to shagreened with sparse several transverse rugulae; the dome in lateral view with a low prominence or mound on its posterior slope; humerus of the dome not or hardly produced laterad; the dome at the humeri narrower than at the bottom; mesopleuron, metapleuron and lateral face of propodeum rugoso-reticulate, with enclosures punctured. Outer surface of foretibia bearing relatively long decumbent-suberect hairs. Petiole longer than postpetiole (excluding helcium); postpetiole not massive. First gastral tergite largely smooth and shining, but sometimes weakly punctured around its articulation with postpetiole.
Minor. - Frons and dorsal face of vertex smooth and shining, or very weakly punctured or rugoso-punctate; area between antennal insertion and eye rugose or rugoso-punctate; preoccipital carina well-developed; median part of clypeus with a zigzag or ramified (but rarely straight) median carina which is usually accompanied with weak rugulae; antenna with a 3-segmented club; scape extending far beyond posterolateral margin of head; maximal diameter of eye shorter than antennal segment X. Promesonotal dome smooth and shining, or in dorsal view concentrically rugose, with a median area smooth and shining or very weakly punctured; the posterior slope of the dome with a low mound which bears several (>2) standing hairs; humerus in dorsooblique view not or hardly produced; mesopleuron, metapleuron and lateral face of propodeum punctured, usually overlain by weak rugoso-reticulation; propodeal spine horn-like or elongate-triangular, narrowly based, directing relatively upward. Petiole longer than postpetiole (excluding helcium); postpetiole not massive.
Recognition: The syntype major of Pheidole peguensis r. yomensis Forel agrees with the majors of Thai populations of Pheidole plagiaria (e.g., Eg01-TH-083). Thus, I here synonymize Pheidole peguensis r. yomensis with P. plagiaria. Three Pheidole minors which are pinned together and labeled as "Ph plagiaria Sm v. moica For .... Mois Cochinchine (Dugas)" were examined (MHNG). The top of the pin is undoubtedly a minor of Pheidole plagiaria, while the middle is the other Pheidole species, and the bottom is Pheidologeton sp. Forel (1911) described " P. plagiaria var. moica " based on the major subcaste, and so I refrain from resolving the synonymy.
This species is characterized among Indo-Chinese species by the combination of the following features: in the major posterior margin of head in full-face view relatively widely and deeply concave; in the major the posteriormost part of the dorsum of vertexal lobe almost transversely rugose; in the major and minor the posterior slope of promosonotal dome with a prominence or mound; in the major outer surface of foretibia bearing relatively long decumbent-suberect hairs; in the minor median part of clypeus with a zigzag or ramified (but rarely straight) median carina which is usually accompanied with weak rugulae. The minor of this species is similar to that of P. binghami, but in the latter median part of clypeus has no rugula and the mound on the posterior slope of promesonotal dome has only a pair of hairs.
Distribution & bionomics: Widely distributed in the Indo-Chinese, Indo-Malayan subregions and Austro-Malayan subregion. Indo-Malayan populations inhabit well-developed forests, and usually nest in rotting logs and wood fragments. On the other hand, Indo-Chinese populations often occur in forest edges and even in open lands adjacent to forests, and usually nest in the soil (Eguchi 2001).
description: Published as part of Eguchi, K., 2008, A revision of Northern Vietnamese species of the ant genus Pheidole (Insecta: Hymenoptera: Formicidae: Myrmicinae)., pp. 1-118 in Zootaxa 1902 on pages 73-77