Umanella caerulea Gauld, 1991

Broad, Gavin, Sääksjärvi, Ilari & Palacio, Edgard, 2010, A new species of Umanella Gauld (Hymenoptera, Ichneumonidae) from Ecuador, ZooKeys 35 (35), pp. 77-90 : 80-82

Umanella caerulea Gauld, 1991

Description. See Gauld (1991). Essentially similar to U. giacometti but differing in the characters listed in Table 1. Only characters that are useful in differentiating U. caerulea from U. giacometti are emphasised here, although complete descriptions of female and male colour patterns are given.

Female. Fore wing length 12–15 mm. Ovipositor length 23–43 mm, ratio of ovipositor to fore wing (1.60) 1.92–2.87 (n=10); smaller specimens with relatively shorter ovipositor, larger specimens with relatively longer ovipositor (but with one exception, see variation). First tergite of metasoma 3.4–3.7 × as long as apically wide, second tergite 2.1–2.6 × as long as apically wide. Second tergite with narrow, drop-shaped median area defined, sides of raised area slightly convex ( Fig. 3A, B ).

Colour: metallic blue, duller towards apex of metasoma, fading to dark brown. Metasoma with purple tinge, sometimes strongly so. Ground colour of metasoma brown. Female from Colombia (BMNH) with metasoma largely brown, but with some blue and purple gloss. Antennae black, except for white, sub-apical annulus on five to seven flagellomeres. Maxillary palps dark brown basally and apically, dull white on third and fourth segments.'Tegula centrally metallic blue, brown around edges. Wing venation, including stigma, dark brown. Wing membrane slightly infuscate basally, distinctly infuscate in apical quarter. Legs with coxae, trochanters and trochantelli shiny, metallic (dark) blue. Fore leg with large apical patch on trochanter (or entire front side) creamy white, extreme apex of trochantellus brown, conspicuous creamy streak along front edge of femur (from apical half to entire length); fore tibia with basal 0.6 brown (slightly paler sub-basally); fore tarsus brown fading to yellowish on third and fourth tarsomeres, fifth tarsomere black. Mid femur with tiny basal patch to conspicuous basal streak creamy; mid tibia brown with dull yellowish mark sub-basally and fading to yellowish on apical quarter (black at extreme apex) ( Fig. 4A, B ) or almost entirely white (black very apically ( Fig. 4C ). Legs otherwise marked as in U. giacometti but pale markings are duller, usually more yellow.

Paratype male (BMNH). Whole insect: Fig. 6 . Fore wing length 7.5 mm, body length (from antennal insertion to apex of genitalia) 7.8 mm. Submetapleural carina complete. First metasomal tergite 2.2 × as long as maximum width ( Fig. 5A ), second tergite 1.6 x as long as wide. Second and third tergites with strong diagonal, basal grooves cutting off raised, central section which is raised posteriorly. First and second tergites with strong setae laterally, first tergite and basal half of second smooth dorsally, metasoma setose dorsally from second half of second tergite. Sclerotized part of first tergite extending to 0.2 of distance between spiracle and hind edge. Some dorsal punctures on apical half of second tergite, following tergites regularly punctate and setose dorsally.

Colour: head and mesosoma metallic blue. Antennae black, white on 7 (22nd to 28th) flagellomeres. Maxillary and labial palps white. Tegula brown. Wing venation, including stigma, dark brown. Wing membrane clear basally, slightly infuscate in apical quarter. Fore leg white on fore side, except apical tarsomere brown. Hind side of fore leg basally white, trochantellus and femur brown; fore tibia pale brown over basal quarter, apex narrowly dark brown; fore tarsus pale brown except apical tarsomere dark brown. Mid leg with coxa and trochanter white, trochantellus brown, fore side of femur brown on basal 0.15, remainder white, fore side of mid tibia vaguely infuscate brown basally and medially, dark brown at very apex, hind side of femur brown, hind side of tibia brown over basal 0.6, slightly paler patch sub-basally, mid tarsus dark brown on first, second and fifth tarsomeres, third and fourth white. Hind leg with metallic blue coxa, metallic darker blue on trochanter and trochantellus, turning to black on femur; apex of hind trochantellus and base of femur narrowly brown; hind tibia black with narrow annulus sub-basally, white on outer side, brown on inner side; hind tarsus dark brown on first, basal 0.7 of second and apical 0.5 of fifth tarsomeres, remainder white. Metasoma with first tergite metallic blue, second and third tergites brown with dark brown apical rims, remaining tergites dark brown; first sternite with sclerotized part metallic blue, sclerotized sections of other sternites brown, membranous parts of sternites white.

Variation. 'Th e single male in BMNH seems to be unusually small and stout, compared to male specimens from Colombia in IAVH and has deformed antennae ( Fig. 7 ). One male in IAVH has the metasoma almost entirely metallic blue. There is variation in the amount of white on the mid tibia of females ( Fig. 4A, B, C ), in the amount of metallic blue colouration on the metasoma and in the relative length of the ovipositor (Table 1). Much of this variation we assume is size-related (smaller specimens seem to be more extensively white and brown), but one female specimen from Colombia in IAVH is particularly stout, with length to breadth ratios of the 1st and 2nd tergites of 3.4 and 2.1, respectively, and the ovipositor only 1.6 x the length of the fore wing (which is relatively large, at 14 mm). The mid tibia of this specimen is almost entirely white. Whether this specimen represents a third species or is just at the extreme end of variation within U. caerulea we are unable to say at present but it would be desirable to see more Umanella specimens from Colombia.

Biology. Nothing is known.

Distribution. Known from from Costa Rica (see Gauld, 1991, Gauld et al., 1998), and now from Colombia: female, Amazonas, PNN Amacayacu, 150m, Malaise trap, 15.X.2001 – 5.XI.2001, 03°46'S, 70°18'W, D. Chota (IAVH); female, Nariño, Barbacoas, 40 m, 28.X.1990, M. Cooper (BMNH); male, Chocó, PNN Utría, 10m, Malaise trap, 1.VII.2000 – 5.VII.2000, 06°01'N, 77°20'W, B. Brown (IAVH); male, Valle, PNN Los Farallones, 650m, Malaise trap, 1.VIII.2000 – 10.IX.2000, 03°26'N, 76°48'W, S. Sarria (IAVH).

Figures

Figure 3. Second tergite of female metasoma of a U. caerulea from Costa Rica b U. caerulea from Colombia c U. giacometti; anterior to the right.

Figure 4. Mid tibia of a female of U. caerulea from Costa Rica b female of U. caerulea from Colombia (BMNH) c female of U. caerulea from Colombia (IAVH) d female of U. giacometti.

Figure 5. First tergite of male metasoma of a U. caerulea (BMNH) b U. caerulea (IAVH) c U. giacometti; anterior to the right.

Figure 6. Paratype male of U. caerulea.

Figure 7. Male of U. caerulea, Colombia (IAVH).