Pholetesor dixianus, Whitfield, 2006

Whitfield, James B., 2006, Revision of the Nearctic species of the genus Pholetesor Mason (Hymenoptera: Braconidae), Zootaxa 1144 (1), pp. 1-94 : 33-34

Pholetesor dixianus , new species

( figs. 20 , 43 , 63 )

Holotype female. Body length 2.0 mm; forewing length 2.4 mm.

Head. Froans 1.2x as broad at midheight as long medially, indistinctly punctate laterally and near clypeus, more coarsely punctate near antennal bases, with faint metallic sheen between punctures; inner margins of eyes strongly converging towards clypeus. Antennae dark brown except lighter scape, slightly shorter than forewing; all but apical 5 flagellomeres with 2 ranks of placodes; flagellomere 2 2.9x as long as broad; flagellomere 14 1.4x as long as broad. palpi pale yellowish distally, tinged with dark brown proximally. Head in dorsal view just over 2x as broad as medially long.

Mesosoma . Mesoscutum finely, distinctly punctate, becoming more weakly and sparsely so posteriorly near scutellum; surface between punctures with faint satiny sheen; mesoscutal width just anterior to tegulae virtually identical to head width. Suctoscutellar scrobe deep, composed of about a dozen sharp, sometimes confluent crenulations; medial portion weakly arched. Scutellar disc slightly longer than anteriorly broad, with widely spaced, fine, weak punctations. Metanotum weakly retracted from scutellum, shallowly excavated mesad sublateral setiferous projections; transverse carinae on either side at about midlength parallel to anterior margin and setting off small transverse depressions, crossed by several weak carinae. Propodeum finely rugulose anteriorly, less densely sculptured posteriorly behind poorly defined transverse carinae; medially with indistinct pentagonal areola, partially obscured posteriorly by coarse longitudinal sculpturing, anteriorly by rugulosity; areola about.25 width of propodeum; propodeal width 2.2x maximum length.

Legs. All coxae mostly dark brown to black with light yellowish tinges apically; legs otherwise bright honey­orange except tips of distal tarsomeres and infuscate hind tarsi and distal 0.2 of hind tibiae. Spines on outer faces of hind tibiae widely scattered, about 25 in number. Inner hind tibial spurs at least 15% longer than outer, about 0.4 length of hind basitarsi. Hind legs slightly thickened.

Wings. Tegulae dark brown, weakly translucent. Forewing venation yellowish brown proximally, becoming evenly deep brownish at and beyond stigma. 2r longer than 1Rs, weakly arched, meeting 1Rs at distinct, approximately 130­degree angle. R1 1.4x as long as stigma, curved, 8x as long as distance from its distal tip to end of 3Rs fold along wing edge. Stigma 2.3x as long as broad. Hindwing with weakly flattened vannal lobe; vannal fringe even, somewhat sparse, short.

Metasoma. Tergite I strongly arched arched in profile, approximately as broad posteriorly as medially long, strongly rugose, with broad medial excavation over anterior third; lateral margins weakly diverging posteriorly. Tergite II subquadrate, slightly broader posteriorly, 2.7x as broad as long medially, with weakly concave hind margin; surface entirely rugose. Tergite III subequal in length and breadth with II but narrowing slightly to rounded posterolateral corners; coarsely rugose throughout, separated from II by an irregular crenulate furrow. Laterotergites yellowish, virtually hidden in dorsal view. Succeeding terga of usual unsculptured, overlapping form. Entire dorsum of metasoma appearing strongly oval in dried specimens. Hypopygium 1.1x as long as hind basitarsus, submedially weakly creased, setting off more translucent, hairless and more flexible medial fold. Ovipositor sheaths approximately equal in length with hypopygium, basally slender, broadening to broad fusiform shape over distal 0.5; in profile more strongly curved ventrally (convex) than dorsally. Ovipositor weakly decurved, becoming more strongly so apically.

Males. Unknown.

Variation. Body length 1.8–2.0 mm; forewing length 2.2–2.4 mm. The 3 examined specimens are extremely similar in coloration, sculpturing, wing venation and metasomal features despite some geographical separation. The North Carolina individual has a more well­defined areola than either of the Texas specimens, but the propodeal background sculpturing is otherwise not unusual.

Final instar larva. Unknown.

Cocoon. Unknown.

Material examined. Holotype female. TEXAS. Crosby , 27­IV­1953 ( R. H. Beamer) . Paratypes: NORTH CAROLINA. Macon Co., Wayah Bald , 5400', 1 female, 20­VI­1957 (W. R. M. Mason) . TEXAS. Kerrvile , 1 female, 13­IV­1959 (W. R. M. Mason) .

Holotype from and deposited in Snow Entomological Museum, University of Kansas; paratypes in CNC.

Hosts. Unknown.

Comments. The long R1, broad ovipositor sheaths, submedially creased hypopygium, broad and heavily sculptured basal metasomal tergites and weak propodeal areola combine to make this a distinctive species. It would be interesting to know how its biology compares to that of P. pinifoliellae (below).

Figures

FIGURES 17–21. Forewings of: 17, Pholetesor bucculatricis (Muesebeck); 18, P. zelleriae Whitfield; 19, P. masoni Whitfield; 20, P. dixianus Whitfield; 21, P. pinifoliellae Whitfield.

FIGURES 39–59. Anterior metasomal tergites, dorsal view, of: 39, Pholetesor masneri (Mason); 40, P. bucculatricis (Muesebeck); 41, P. zelleriae Whitfield; 42, P. masoni Whitfield; 43, P. dixianus Whitfield; 44, P. pinifoliellae Whitfield; 45, Pholetesor rhygoplitoides Whitfield; 46, P. bedelliae (Viereck); 47, P. chiricahuensis Whitfield; 48, P. longicoxis Whitfield; 49, P. powelli Whitfield; 50, P. thuiellae Whitfield; 51, P. rohweri (Muesebeck); 52, P. variabilis Whitfield; 53, P. viminetorum (Wesmael); 54, P. caloptiliae Whitfield; 55, Pholetesor ornigis (Weed); 56, P. salalicus (Mason); 57, P. salicifoliellae (Mason); 58, Pholetesor circumscriptus (Nees); 59, P. pedias (Nixon).

FIGURES 60–71. 60–62, Ovipositor apparati, lateral view, of: 60, Pholetesor bucculatricis (Muesebeck); 61, P. zelleriae Whitfield; 62, P. masoni Whitfield. 63–65: Apex of female metasoma, lateral view, of: 63, P. dixianus Whitfield; 64, P. pinifoliellae Whitfield; 65, P. rhygoplitoides Whitfield. 66: Ovipositor apparatus, lateral view, of P. bedelliae (Viereck). 67, 68: Apex of female metasoma, lateral view, of: 67, P. chiricahuensis Whitfield; 68, P. longicoxis Whitfield. 69: Ovipositor apparatus, lateral view, of P. powelli Whitfield. 70, 71: Apex of female metasoma, lateral view, of: 70, P. thuiellae Whitfield; 71, P. rohweri (Muesebeck).