Apanteles diatraeae

General description: 

Type locality. CUBA, Central Mercedes.
Holotype. ♀, NMNH (examined).
Material Examined. 1 ♀, paratype (CNC), CUBA: Central Mercedes, ix.1918,
T.E. Holloway, ex Diatraea sp.; 2 ♀ (CNC), UNITED STATES: AZ, Tucson,
23.vi.1923, E.V. Walter.
Description. Female. Body color: body mostly dark except for some sternites
which may be pale. Antenna color: scape and/or pedicel dark, flagellum pale. Coxae
color (pro-, meso-, metacoxa): pale, dark, dark. Femora color (pro-, meso-, metafemur):
anteriorly dark/posteriorly pale, dark, dark. Tibiae color (pro-, meso-, metatibia): pale,
pale, dark. Tegula and humeral complex color: both dark or both pale (?). Pterostigma
color: entirely pale or transparent, translucent. Fore wing veins color: mostly white or
entirely transparent. Antenna length/body length: antenna very short, barely or not
extending beyond mesosoma length. Body in lateral view: distinctly flattened dorso–
ventrally. Body length (head to apex of metasoma): 2.1–2.2 mm. Fore wing length:
2.1–2.2 mm. Ocular–ocellar line/posterior ocellus diameter: 2.6 or more. Interocellar
distance/posterior ocellus diameter: 2.3–2.5. Antennal flagellomerus 2 length/width:
2.0–2.2. Antennal flagellomerus 14 length/width: 1.1–1.3. Length of flagellomerus
2/length of flagellomerus 14: 1.7–1.9. Tarsal claws: with single basal spine–like seta.
Metafemur length/width: 2.8–2.9. Metatibia inner spur length/metabasitarsus length:
0.4–0.5. Anteromesoscutum: mostly smooth or with shallow sparse punctures, except
for anterior 0.3 where it has deeper and/or denser punctures. Mesoscutellar disc:
mostly smooth. Number of pits in scutoscutellar sulcus: 7 or 8. Maximum height of
mesoscutellum lunules/maximum height of lateral face of mesoscutellum: 0.6–0.7. Propodeum areola: completely defined by carinae, but only partial or absent transverse
carina. Propodeum background sculpture: partly sculptured, especially on posterior
0.5. Mediotergite 1 length/width at posterior margin: 2.0–2.2. Mediotergite 1 shape:
more or less parallel–sided. Mediotergite 1 sculpture: mostly sculptured, excavated
area centrally with transverse striation inside and/or a polished knob centrally on posterior
margin of mediotergite. Mediotergite 2 width at posterior margin/length: 1.6–
1.9. Mediotergite 2 sculpture: mostly smooth. Outer margin of hypopygium: with a
wide, medially folded, transparent, semi–desclerotized area; usually with 4 or more
pleats. Ovipositor thickness: anterior width at most 2.0 × posterior width (beyond ovipositor
constriction). Ovipositor sheaths length/metatibial length: 0.8–0.9. Length of
fore wing veins r/2RS: 1.4–1.6. Length of fore wing veins 2RS/2M: 1.1–1.3. Length
of fore wing veins 2M/(RS+M)b: 0.7–0.8. Pterostigma length/width: 2.6–3.0. Point
of insertion of vein r in pterostigma: about half way point length of pterostigma. Angle
of vein r with fore wing anterior margin: more or less perpendicular to fore wing margin.
Shape of junction of veins r and 2RS in fore wing: strongly angulated, sometimes
with a knob.
Molecular data. No molecular data available for this species.
Biology/ecology. Gregarious, dirty whitish cocoons, cemented together in a long
slender row but not surrounded by loose silk (Muesebeck 1921). Hosts: Crambidae
(commonly called Pyralidae in older literature), Diatraea grandiosella, D. impersonatella,
D. lineolata, D. magnificata, D. muellerella, D. saccharalis, Diatraea sp. In the
past, the Pyralidae species Galleria mellonella has also been recorded as a host (Paddock
1933), a record that might best be questioned.
Distribution. Widely distributed in southern US, Mesoamerica and the northern
part of South America; introduced in France and India (Yu et al. 2012). We have no
reason to suspect that this species occurs in ACG.
Comments. This is the commonest braconid parasitoid of Diatraea spp., along
with Cotesia flavipes, but it does not appear to extend much into South America (Austin
and Dangerfield 1989).

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith