Pheidole laevicolor, Eguchi, Katsuyuki, 2006

Eguchi, Katsuyuki, 2006, Six new species of Pheidole Westwood from North Vietnam (Hymenoptera, Formicidae), Revue Suisse de Zoologie 113 (1), pp. 115-131 : 115

Pheidole laevicolor sp. n.

Figs 4A-G

Pheidole sp. eg-114 : Eguchi et al., 2004 (ecological study).

HOLOTYPE. - Major from colony Eg01-VN-130. Type locality: Tam Dao N. P. (21°27’N, 105°38’E, ca. 1000 m alt.), Vinh Phuc, Vietnam [K. Eguchi leg., 6/xi/2001]. Depository: IEBR.

PARATYPES. - 14 majors and 15 minors from the same colony to which the holotype belongs. Depository: IEBR, MHNG, MCZC, BMNH, NHMW, FSKU, ACEG.

NON-TYPE MATERIAL EXAMINED. - Vietnam: Thai Nguyen: My Yen Commune Forest (21°35’N, 105°36’E), Na Hau Village [Eg01-VN-160]; Bac Giang: W. Yen Tu N. P. (21°10- 11’N, 106°43-44’E, 170-415 m alt.) [B&E03-01, -30, -40]; Ha Tay (misspelled as “Ha Tai” on the labels): Ba Vi N. P. (21°03’N, 105°22’E, 1100-1200 m alt.) [Eg99-VN-129, Eg02-VN-033]. Eguchi’s informal species code “ Pheidole sp. eg-114 ” has been applied to these specimens.

DIAGNOSIS. - Dorsal and lateral faces of head and promesonotal dome smooth and shining (minor); vertex and dorsal and lateral facecs of vertexal lobe reticulate, with enclosures punctured and dull (major); hypostoma with 3 conspicuous median processes in addition to the process just mesal to mandibular base (major); promesonotal dome at most with an inconspicuous prominence on its posterior declivity (major and minor).

DESCRIPTION. - Major: TL 2.5-3.1 mm, HL 1.06-1.20 mm, HW 0.98-1.08 mm, SL 0.49-0.55 mm, FL 0.86-0.76 mm, CI 90-92, SI 50-52, FI 67-72 (N=5); head in full-face view very weakly convex laterad, broady concave posteriorly, in profile weakly or hardly impressed on vertex; frons longitudinally rugose; vertex and dorsal and lateral faces of vertexal lobe reticulate, with enclosures punctured and dull; frontal carina very weak or vestigial just as rugulae; antennal scrobe absent; median part of clypeus almost smooth, sometimes with an inconspicuous median longitudinal carina; hypostoma with 3 median processes in addition to the process just mesal to each mandibular base (lateral processes); lateral processes well developed, as large as lateral ones of the three median processes; antenna with a 3-segmented club; scape exceeding midlength of head to some extent; EL>LASX; LG 1.4-1.7 times as much as EL; promesonotal dome without a prominence on its posterior declivity; dorsolateral part of the dome weakly produced laterad; anterodorsal, mediodorsal and lateral faces of the dome almost smooth and shining, often sparsely with weak rugulae; mesopleuron and lateral face of propodeum weakly punctured, often with a smooth area on the lower part of mesopleuron; propodeal spine elongate-triangular, sometimes with a blunt apex, narrowly or moderately based; petiole much longer than postpetiole (excluding helcium); petiolar node in anterior view weakly or very weakly concave dorsally; postpetiole not massive, in dorsal view usually produced well laterad, 1.7-1.9 times as broad as petiolar node; first gastral tergite weakly punctured on its anterior 1/4-1/3; body deep yellowish brown, with darker gaster and paler appendages.

Minor: TL 1.6-2.1 mm, HL 0.50-0.58 mm, HW 0.42-0.50 mm, SL 0.47- 0.58 mm, ML 0.65-0.79 mm, FL 0.49-0.62 mm, CI 84-88, SI 108-116, FI 117-124 (N=5); body yellowish brown; head smooth and shining; preoccipital carina complete but very weak dorsally; median part of clypeus smooth and shining, without a median longitudinal carina; antenna with a 3-segmented club; scape exceeding posterior margin of head at least by half length of second antennal segment; EL as much as or a little more than LASX; promesonotal dome largely smooth and shining, with several weak rugulae anterodorsally, in profile without or with an inconspicuous prominence on its posterior declivity; mesopleuron and lateral face of propodeum weakly punctured; propodeal spine elongate-triangular, narrowly based; petiole much longer than postpetiole (excluding helcium); postpetiole not massive, 1.5-1.9 times as broad as petiolar node; gaster smooth and shining.

REMARKS. - This species is very similar to P. rinae taipoana Wheeler but distinguished from the latter by the following characteristics: the major of the latter having area in front of a transverse impression on vertex sparsely with weak longitudinal rugulae, with interspaces smooth and shining, and the vertexal impression deep.

DISTRIBUTION. - N. Vietnam.

BIONOMICS. - This species inhabits forests (including forest edges) from lowlands to hilly areas (up to 1200 m alt. in N. Vietnam), and nests in the soil (see also Eguchi et al., 2004).