Pheidole vieti, Eguchi, 2008

Eguchi, Katsuyuki, 2008, A revision of Northern Vietnamese species of the ant genus Pheidole (Insecta: Hymenoptera: Formicidae: Myrmicinae), Zootaxa 1902 (1), pp. 1-118 : 100-103

Pheidole vieti sp.n.

Figs. 28a–h

Pheidole sp. eg-112. Eguchi, Bui et al. 2005: 91 (checklist).

Type material examined: Holotype: major, Ba Vi N.P., 400–600 m alt., Ha Tay (misspelled as “ Ha Tai ”), Vietnam [K. Eguchi leg., colony: Eg99-VN-092] ( IEBR); paratypes: 5 minors from the same colony as holotype ( IEBR, MCZC, MHNG & ACEG).

Other material examined: Vietnam: Vinh Phuc: Tam Dao N.P., 21°27’N, 105°38’E, 950 m alt. [Sk. Yamane]; Ha Tay (misspelled as “ Ha Tai ”): Ba Vi N.P., 600 m alt. [Eg99-VN-104]. Eguchi’s informal species code “ Pheidole sp. eg-112” applies to this species .

Worker measurements & indices: Holotype (major). — HL 1.21 mm; HW 1.16 mm; CI 95; SL 0.62 mm; SI 54; FL 0.81 mm; FI 70.

Nontype major (n=1). — HL 1.22 mm; HW 1.17 mm; CI 96; SL 0.60 mm; SI 51; FL 0.79 mm; FI 68.

Minor (n=3, including one paratype minor). — HL 0.59–0.64 mm; HW 0.55–0.60 mm; CI 92–94; SL 0.59–0.61 mm; SI 103–109; FL 0.63–0.68 mm; FI 114–117.

Worker description

Major. — Body yellowish brown. Head in lateral view not impressed on vertex; frons and anterior part of vertex rugose longitudinally; posterior part of vertex sparsely and interruptedly sculptured with longitudinal rugulae; dorsum of vertexal lobe shagreened or only very weakly rugoso-punctate; frontal carina inconspicuous, present just as rugula(e); antennal scrobe almost absent; clypeus without a median longitudinal carina; median prosess of hypostoma variable in its development, conspicuous (nontype major) or completely absent (the holotype); submedian and lateral processes conspicuous; antenna with a 3-segmented club; eye consisting of less than 20 ommatidia; maximal diameter of eye shorter than antennal segment X. Promesonotal dome smooth and shining, in lateral view lacking a mound on its posterior slope; humerus of the dome not produced; the dome at the humeri much narrower than at the bottom; mesopleuron weakly punctured largely; lateral face of propodeum almost smooth; metapleuron with several rugulae. Petiole a little longer than postpetiole (excluding helcium); postpetiole relatively massive. First gastral tergite smooth and shining excluding very weakly punctured area around its articulation with postpetiole.

Minor. — Body yellowish brown. Frons and vertex smooth; dorsolateral part of head partly to largely rugoso-punctate weakly or dimly; preoccipital carina complete but weak dorsally; median part of clypeus smooth and shining; the median longitudinal carina absent, or present at most anteriorly; antenna with a 3-segmented club; scape exceeding posterior margin of head by 1.5 times the length of antennal segment II or more; eye consisting of only ca. 8–12 ommatidia; maximal diameter of eye shorter than antennal segment X. Promesonotal dome largely smooth and shining, in lateral view lacking a mound on its posterior slope; humerus of the dome in dorso-oblique view not produced; mesopleuron punctured; metapleuron and lateral face of propodeum very weakly punctured or almost smooth; propodeal spine elongate-triangular. Petiole almost as long as or only a little longer than postpetiole (excluding helcium); postpetiole relatively massive.

Recognition: This species has the following combination of diagnostic characteristics: in the major head in lateral view not impressed on vertex; in the minor head and promesonotal dome largely smooth and shining; in the major dorsum of vertexal lobe shagreened or only very weakly rugoso-punctate; in the major frontal carina inconspicuous, present just as rugula(e), and antennal scrobe almost absent; in the major submedian processes of hypostoma conspicuous; eye relatively reduced, consisting of ca. 13–19 ommatidia in the major and 8–12 ommatidia in the minor; in the major and minor promesonotal dome without a mound on its posterior slope; in the major and minor humerus of promesonotal dome not produced laterad; in the major and minor postpetiole relatively massive.

This species is similar to Pheidole vulgaris Eguchi , but head is shorter but higher and postpetiole is more massive in the major of the former than in that of the latter.

Distribution & bionomics: Known only from N. Vietnam.

Figures

FIGURE 28a–d, Pheidole vieti sp.n., holotype (major) [Eg99-VN-092] — a, head in full-face view; b, head in lateral view; c, mesosoma and waist in dorsal view; d, mesosoma and waist in lateral view.