Polistes (Polistella) flavitarsis Selis, 2018

Selis, Marco, 2018, Revision of the genus Polistes Latreille (Hymenoptera: Vespidae: Polistinae) in the Philippine Islands, Zootaxa 4531 (4), pp. 507-531 : 515-518

Polistes (Polistella) flavitarsis Selis , sp. nov.

( Figs. 22–31 )

Diagnosis. This species is similar to P. williamsi Petersen, 1990 , from which it differs by [characters of P. williamsi in square brackets]: ground color dark reddish-brown ( Figs. 22–23 ) [ground color dark red ( Figs. 63–64 )], mesoscutum without yellow markings [mesoscutum with two yellow lines], yellow tarsi ( Fig. 28 ) [brown tarsi ( Fig. 65 )], wings darkened [wings hyaline with light brownish tinge], T1 and female clypeus clearly more elongated, and male flagellomeres more than twice as long as wide ( Fig. 30 ) [male flagellomeres less than twice as long as wide ( Fig. 66 )]. Both species belong to the “ Stenopolistes ” species-group, showing appressed ocelli and the jugal lobe of the hind wing reduced.

Material examined. HOLOTYPE: ♂, labeled “PH—Mindanao, Cotabato, Kidapawan / I.2015 /Leg. local collector” ( MSNVE) . PARATYPES: PHILIPPINES: MINDANAO: Agusan, San Francisco , X.2017, 1 ♀ ( RMNH) ; Cotabato, Kidapawan , I.2015, 1 ♀ ( MSNVE) ; Davao, Governor Generoso, X.2017, 1 ♀ ( RMNH); Davao, Governor Generoso , XI.2017, 4 ♀ (2♀ MSVI; 2♀ OLML) ; Pantukan, IX.2015, 1 ♂ 1♀ ( MSVI); Sarangani, Kiamba, I.2016, 1 ♀ ( MSNVE); Sarangani, Kiamba , XII.2016, 1 ♀ ( MSVI) .

Description. FEMALE. Body length 12–14 mm; fore wing length 1 4–17 mm

Head in frontal view about as high as wide ( Fig. 24 ); in dorsal view temples converging behind eyes. Vertex sloping down behind posterior ocelli. Distance between posterior ocelli shorter than ocellar diameter. Gena in lateral view about 0.56× as wide as eye at ocular sinus; occipital carina fine but distinct, absent in ventral half of gena. Inner eye margins weakly convergent ventrally. Antennal sockets as close to inner eye margin as to each other; interantennal space raised in a small tubercle. Clypeus in frontal view about as high as wide; in lateral view weakly convex from base to apex; length of lateral margin of clypeus lying along inner eye margin longer than diameter of antennal socket and about as long as the length of malar space; free apical part 0.25× as long as length of basal part, weakly projecting below. Antennal scape about 3.3× as long as its maximum width; F1 about 3.4× as long as its maximum width, about 1.2× as long as the length of F2 and F3 combined; F2–F9 longer than wide, becoming progressively shorter; F10 bullet-shaped, 1.7× as long as basally wide ( Fig. 25 ).

Pronotal carina sharply raised, produced into a very short lamella, regularly curved on lateral faces, almost reaching ventral corner of pronotum. Mesoscutum distinctly convex, slightly longer than wide between tegulae. Scutellum distinctly convex anteriorly, flattened posteriorly. Disc of metanotum flat, in lateral view smoothly passing from posterior margin of scutellum; lateral thirds of metanotum weakly rounded. Propodeum with a short dorsal face behind metanotum, then smoothly passing into posterior face; posterior face of propodeum with a shallow triangular depression posteriorly; no distinct separation between faces.

T1 elongated, about 1.3× as long as its apical width, in lateral view strongly angled dorsally just behind basal slit for reception of propodeal suspensory ligament, then flattened to apical margin ( Fig. 26 ). T 2 in dorsal view enlarged in basal half, then parallel-sided. S 2 in lateral view regularly convex from base to apex ( Fig. 27 ).

Clypeus with scattered large punctures, each bearing sharply pointed golden bristle; tomentum restricted to the dorsal half of clypeus. Mandible with shallow scattered punctures. Face below ocular sinus impunctate; frons covered with small punctures, interspaces larger than point diameter. Gena impunctate and dull, malar space with some small deep punctures. Pronotum with shallow flat-bottomed punctures, denser on dorsal face, becoming sparser on lateral faces. Mesoscutum punctured like pronotum anteriorly, punctures becoming very shallow posteriorly. Scutellum with deeper and denser flat-bottomed punctures. Metanotum with some indistinct punctures laterally. Mesepisternum and mesosternum with dense flat-bottomed punctures, interspaces as long or slightly shorter than punctures diameter, but never forming a reticulation. Metaepisternum dorsally with striae, ventrally with very shallow sparse punctures. Propodeum transversely striate, striae weak and almost indistinct on median third of posterior face, stronger on dorsal faces. Metasomal segments entirely micropunctate, with some scattered indistinct punctures on sterna. Head and mesosoma with dense sericeous brownish pubescence, becoming grayish ventrally; metasoma with similar pubescence, but black in color.

Color. Dark reddish-brown; following parts pale yellow: posterior margin of pronotum, short line along pronotal carina on lateral face, anterior margin of metanotum, short narrow lines on propodeum, thin apical margin of T1–T3 and S2–S3, apical spot on all femora, tarsi from apex of basitarsus ( Fig. 28 ); following part black: spots on frons, ventral face of head, anterior face and ventral corner of pronotum, margins of mesoscutum, irregular markings on mesepisternum, metaepisternum and propodeum, base of all terga and sterna, femora except apex; ventral margin of clypeus dirty orange. Wings fuscous, with weak golden reflections, purplish reflections on marginal cell; wing venation black.

MALE. Body length 12 mm; fore wing length 14–15 mm.

Like female, except more slender and elongated appearance; clypeus weakly rounded apically, in lateral view more strongly convex in apical half ( Fig. 29 ); ventral lobe of eye greatly developed and strongly bulging; gena in lateral view 0.56× as wide as eye at ocular sinus; antenna very long, all flagellomeres more than 2× as long as wide, F1 4.1× as long as wide, F11 straight and apically rounded, F2–F11 ventrally with tyloids, on F2–F4 tyloids present as a shallow carina, on following flagellomeres tyloids present as two rounded tubercles becoming stronger apically ( Fig. 30 ); S7 with convergent sides, slightly sinuate apically, apical margin almost truncate with two lateral tubercles, apical third of sternum with a semicircular depression delimited by a median tubercle ( Fig. 31 ).

Coloration as in female, but face, mandible and S7 entirely yellow. Yellow markings on mesosoma more extensive.

Cromatic variability. This species shows a certain variability in the extension of yellow markings, which can be reduced, especially on propodeum and metasoma. The couple from Pantukan shows a darker coloration, black with dark red markings and very reduced yellow markings, the female clypeus is black with a median red marking. The yellow tarsal coloration is, however, constant in all specimens.

Etymology. The specific name is from the Latin flavus (=yellow) and tarsus (=tarsus), in reference to the yellow tarsi of this species.

Distribution. Philippine Islands: Mindanao.

Figures

FIGURES 22–26. Polistes (Polistella) flavitarsis Selis, sp. nov. 22, 24–26, ♀. 23, ♂. 22, Habitus of female paratype. 23, Habitus of holotype. 24, Head in frontal view. 25, Antenna in lateral view. 26, T1 in lateral view.

FIGURES 27–31. Polistes (Polistella) flavitarsis Selis, sp. nov. 27–28, ♀. 29–31, ♂. 27, S2 in lateral view. 28,Hind tarsi in dorsal view. 29, Head in frontal view. 30, Antenna in lateral view. 31, S7 in ventral view.

FIGURES 63–66. Polistes (Polistella) williamsi Petersen, 1990. 63, 65, ♀. 64, 66, ♂. 63–64, Habitus. 65, Hind tarsi in dorsal view. 66, Antenna in lateral view.