Pholetesor zelleriae, Whitfield, 2006

Whitfield, James B., 2006, Revision of the Nearctic species of the genus Pholetesor Mason (Hymenoptera: Braconidae), Zootaxa 1144 (1), pp. 1-94 : 20

The zelleriae ­group

Pholetesor zelleriae , n. sp., has been placed in a group by itself, although in many respects it appears intermediate between the bucculatricis ­ and pinifoliellae ­ groups. It possesses the following combination of species­group level character states: 1) metanotum weakly retracted from scutellum, barely or not exposing mesothoracic postphragma; 2) propodeal areola and transverse carinae weak or absent; 3) metasomal tergite I broad, coarsely sculptured; 4) tergite II broad, subqradrate, coarsely sculptured and as long as III down midline; 5) tergite III heavily sculptured throughout, with rounded posterolateral corners; 6) tergite IV unmodified, overlapped by III and similar in appearance to succeeding terga; 7) sternites 3–6 of female not split anteromedially; 8) hypopygium evenly sclerotized to medial fold, not strongly produced at tip; 9) ovipositor sheaths arising below midheight of valvifers; 10) volsellae of male genitalia each with 3 setae on medioventral edge; 11) gonobase (basal ring) of male genitalia transverse, about half as long as proximal breadth of genital capsule; 12) final instar larva with 1 pair of labial setae; 13) final instar larva with 1 seta on each maxilla; 14) cocoon of typical blunt­oblong microgastrine form, whitish, with wispy, fine loose threads exteriorly, spun in host's needle mine damage on Pinus ; 15) hosts are needle and sheath miners on Pinus spp.

The zelleriae ­ group differs from the bucculatricis ­ group in host specialization, cocoon­spinning behavior, position of origin of the ovipositor sheaths, the loss of the propodeal areola and transverse carinae, and in the number of volsellar setae in the male genitalia. Most similar to the zelleriae ­ group in many features is the pinifoliellae ­ group, which differs only in having the hypopygium submedially weakly creased, setting off a narrow, medial, somewhat translucent and flexible region which is usually produced apically. As I consider this hypopygial character to be of potential strong phylogenetic significance, I have not lumped the two groups. Pholetesor masneri is also similar, but is easily recognized by the fourth metasomal tergite being fused to the third and sculptured more or less throughout.