Preseucoela Buffington, 2004

Buffington, Matthew L., 2004, The description of Preseucoela Buffington, new genus, with notes on the status of Nearctic species of Agrostocynips Diaz (Hymenoptera: Figitidae: Eucoilinae), Zootaxa 408 (1), pp. 1-11 : 2-5

Preseucoela Buffington , new genus

Chrestosema Förster , in part.

Type species: Chrestosema pallidipes Ashmead 1894: 68–69 , by present designation.

Diagnosis. Orbital furrows meeting malar sulcus with smooth curve. Genal carina absent. Conical projections present on malar space. Pronotal struts present between posterior margin of pronotal plate and anterior margin of mesoscutum. Mesoscutal keel present or absent. Scutellar plate with two distinct tubercles. Scutellar disk lacking projections. R1 of forewing always tubular and pigmented; radial cell always closed.

Differs from Moneucoela Kieffer by lacking lateral and posterior projections of the scutellum. Differs from Zaeucoila Ashmead and Agrostocynips Diaz by lacking genal carinae (reduced but distinct in Agrostocynips ), and presence of paired tuberacles on dorsal surface of scutellar plate ( Zaeucoila and Agrostocynips have multiple tubercles). Differs from Ganaspidium Weld by presence of orbital furrows, presence of pronotal struts and possession of a large pronotal plate (pronotal plate in Ganaspidium 1/3 to 1/4 as wide as head).

Description. Head. Glabrous except for sparse setae along orbital furrows and malar space. Ocellar hair patches lacking. Orbital furrows (Fig. 2, OF) originating above midline of toruli; furrow runs along medial margin of compound eye, then parallel to malar sulcus after gently curving medially, resulting in what appears to be two malar sulci (the true malar sulcus being more ventral). Malar sulcus simple. Malar space smooth with a single prominent to reduced conical protuberance. Genal carina absent.

Antenna. Female: 13 segments, moniliform, semi­clavate; segment 3 slightly longer than remaining flagellomeres; rhinaria present on segments 3–13. Male: 15 segments, filiform; rhinaria present on segments 3–15. Segments 4–15 subequal in length. Segment 3 excavated laterally, curved outwardly; segment 3 slightly longer than 4.

Pronotum. Pronotal plate large, half as wide as head, with sparse setae along dorsal margin; pronotal fovea open laterally. Pronotal struts present (Fig. 3, PST); no well defined pronotal triangle. Pronotal impression absent. Lateral aspect of pronotum smooth and sparsely setose. Lateral pronotal carina absent.

Mesoscutum. Smooth with a few sparse setae along anterior margin. Mesoscutal keel present (Fig. 3, MSK) or absent; keel reaching posterior 1/3 of mesoscutum when present, occasionally meeting posterior margin of mesoscutum; keel tapering soon after point of origin at anterior margin of mesoscutum, then maintaining constant width posteriorly. No other sculpture present.

Mesopectus. Upper part and lower part of mesopleuron smooth and glabrous. Dorsal margin of mesopleural triangle distinct, lower margin indistinct. Mesopleural carina simple, well defined. Lower portion of mesopleuron bordered by a ventral carina with a distinct anterior surcoxal depression.

Scutellum. Scutellar plate small, revealing dorsal sculpted surface of scutellar disk (Fig. 3); mid­pit of scutellar plate situated centrally to posteriorly; two distinct tubercles (Figs. 3 and 4, SCT) present anterior of mid­pit, sometimes accompanied by setae. Dorsal surface of scutellum coarsely alveolate with setiferous pits; lateral and posterior margins rounded. Scutellar plate ranging from close to well elevated above surface of scutellar disk (Figs. 5 and 6, arrow). Lateral and posterior projections absent.

Metapectal­propodeal complex. Metapectus glabrous to variably setose (long, thin setae); dense setal patch present, ventrally located near antero­ventral cavity; scattered setae along posterior margin. Spiracular groove with distinct dorsal margin; ventral margin distinct to absent. Posterior margin of metapectus ridged. Metapleural ridge present, well defined to reduced; submetapleural ridge reduced. Anteroventral cavity present, densely setose. Propodeum covered in longer, moderately dense setae. Propodeal carinae subparallel, merging towards midline halfway between posterior margin of scutellum and dorsal margin of nucha; auxiliary propodeal carinae indistinct. Nucha glabrous.

Wings. Hyaline, densely covered with setae. R1 of forewing always tubular and pigmented; radial cell always closed; radial cell as deep as long. Apical fringe present, short.

Legs. Procoxae slightly smaller than either meso­ or metacoxae; all coxae sparsely setose with no apparent banding or patches of setae. Femora sparsely setose, with increased density of appressed setae on tibiae and tarsomeres.

Metasoma. Female: subequal in size to mesosoma. Hairy ring present at base of syntergum; hairy ring broken at extreme dorsal margin and incomplete ventrally; hairy ring comprised of smaller, dense setae anteriorly and longer, singly spaced setae posteriorly; remainder of metasoma glabrous. Micropores present on terga 5–8 (terga posterior to syntergum). Terga posterior to syntergum directed ventrally at 70 degree angle relative to syntergum. Male: as in female but terga posterior to syntergum directed ventrally at 90 degree angle.

Biology. Circumstantial evidence and phylogenetic evidence suggests members of Preseucoela are parasitoids of Agromyzidae (see biology section of P. imallshookupis and P. pallidipes below).

Distribution. Neotropical Region: Argentina, The Bahamas, Bolivia, Colombia, Costa Rica, Dominica, Ecuador, El Salvador, Guatemala, Honduras, Mexico, Panama, Venezuela, West Indies. Nearctic Region USA: Arizona, New Mexico.

Etymology. Pres ­ named for Elvis Aaron Presley; ­ eucoela, a suffix frequently used by J.J. Kieffer in describing Neotropical eucoiline genera.

Discussion. Phylogenetic evidence (molecular: 28S rDNA, COI mtDNA; external morphology) suggests this genus is a member of the Zaeucoila group of genera (Buffington, unpublished). Synapomorphies include: orbital furrows present (somewhat reduced in Agrostocynips ; presence of struts/braces connecting pronotal plate with anterior margin of mesoscutum; presence of conical protuberances on malar space (also present in Ganaspidium ); presence of mesoscutal keel (reduced/absent in P. pallidipes and P. heratyi ); compact, stout habitus (also present in some, but not all, members of the Gronotoma group). The most common host for members of this clade are leaf­mining Agromyzidae (the apomorphic genera Dettmeria , Dicerataspis and Lopheucoila are parasitic on fruit infesting Diptera ); ergo, the likely host for species of Preseucoela are Agromyzidae (discussed further below). Because species of Preseucoela possess a scutellar plate similar to that of Ganaspidium (both have narrow glandular release pits; both possess paired tubercles anteriorly), there are often specimens of Preseucoela in collections misidentified as Ganaspidium . Further, since P. imallshookupis possesses a mesoscutal keel (see description below), specimens of this taxon are often found in collections misidentified as Zaeucoila .

Included species: Preseucoela pallidipes (Ashmead) , n. comb., Preseucoela heratyi Buffington, n. sp. and Preseucoela imallshookupis Buffington , n. sp.