Smicromorpha masneri Darling, 2009

Darling, Chris, 2009, A new species of Smicromorpha (Hymenoptera, Chalcididae) from Vietnam, with notes on the host association of the genus, ZooKeys 20 (20), pp. 155-163 : 157-162

Smicromorpha masneri Darling , sp. n.

urn:lsid:zoobank.org:act:17AE3CCE-6B3F-48B2-818B-005EB5A4E5A4

Figs 1–3, 5, 9

Description. The complete description is the detailed subfamily description in Naumann (1969) (= description of Smicromorpha Girault , sensu Naumann, 1986), augmented with the measurements and characters which follow below.

Female (n=4). Body length: 4.2–5.1mm. Forewing length: 2.3–2.6 mm.

Colour (Figures 1 and 2): Predominantly pale yellow to white, darker dorsad. Mesoscutum with light brown areas, a diffuse circle on midlobe of mesoscutum and along transscutal articulation, and dark brown along notauli. Axilla and lateral panel of axilla dark brown to black. Apex of scutellum light brown. Lateral panel of metanotum dark brown. Propodeum white. Fore and mid legs white, hind legs dark yellow dorsad, white below, femoral teeth black, tibia yellow, tarsus white. Metasoma brown, darker above, petiole dark brown but yellow-white basad. Antenna yellow. Forewing hyaline, darker on disc and along setal lines. Pubescence: Head, mesosoma, hind femur with short, appressed setae. Flagellar setae moderately long, suberect.

Head: In frontal view transverse, wider than high, width/height approx. 1.4. In dorsal view, subquadrate, wider than long, width/length 1.7–2.3. Compound eye moderately large. Ocelli moderately large, POL/OOL 0.7–0.9, OD/OOL approx. 0.7, OS greater than OD, frons between median ocellus and scrobes with

Figures Ι–3. Smicromorpha masneri sp. n., holotype female: Ι lateral habitus 2 mesosoma dorsal view 3 antenna – inset, apical flagellomeres, paratype #1, female, right antenna.

weak longitudinal groove. Malar sulcus (subocular suture sensu Naumann) indistinct (distinct in S. lagynos ), M/MAE 0.3–0.4. Antennal scrobes deep, carinate, lateral margin widely separated from compound eye, SW/FW approximately 0.5, UF/LF 2.6–3.2. Vertex and upper frons minutely coriarious (weaker than S. lagynos , reticulate-punctate sensu Naumann), lower frons and clypeus weakly striate, anterior tentorial pits large and distinct (indistinct in S. lagynos ). Antenna (Fig. 3): F1, F2 1.1–1.3, 1.1–1.5 × as long as wide, respectively. F1 0.5–0.7 × as long as F2. F6 and F7 either fused or separate (Fig. 3; see also Variation section), if F6 and F7 separate, F7 subequal or shorter than F6 (longer in S. lagynos , as in Naumann 1986, his fig, 6). Flagellum fusiform.

Mesosoma: Pronotal collar laterally carinate. Mesopleural sutures as in S. lagynos . Upper mesopleuron rugose-punctate, mesopleural depression weakly strigose (cf. strongly strigose in S. lagynos ), ventral mesopleuron transverse-strigose. Propodeum posteriorly convex; spiracular sulcus indistinct. Hind leg: coxa 3.5–4.1 × as long as high. Femur 1.7–2.0 × as long as high, with a weak ventral process and well-developed comb of fine teeth. Tibia slender, dorsal furrow about 0.25 as long as tibia (cf. longer in S. lagynos , 0.3–0.6 as long as tibia). Apical tarsal segment slender. Forewing: shape normal. Stigmal vein shorter than marginal vein; angle between stigmal and marginal veins slightly obtuse. Stump of basalis present.

Petiole: Length/width approximately 3.5, length/height 3.6–4.1 (Figs. 5, 9). Dorsally minutely reticulate-punctate, without paired dorsal carinae (Fig. 9, cf. Fig. 10, S. lagynos ); transverse lamina indistinct, not extending posteroventrally to midlength of petiole; lateral margins not distinctly carinate in posterior 0.5.

Male. Unknown.

Etymology. The species epithet is a patronym commemorating Dr. Lubomír Masner’s 75 th birthday.

Type material. Holotype: Female. VIETNAM: Thua Thien-Hue Province, Bach Ma National Park, secondary forest. Ex : nest of Oecophylla smaragdina . 16°15’1”N, 107°52’24”E, 26m. June 27, 2000. Reared at Toronto Zoo, August 9–13, 2000. T. Mason and L. Attard. DC Darling Slide 2067 (antenna). (point-mounted, ROME)

Paratypes: Females (n=3, ROME, IEBR), all same data as holotype. 1. Cardmounted, missing right hind leg, DNA voucher UCR, D2651 ( ROME). 2. Cardmounted, right forewing and hindwing on separate point, left femur, tibia and tarsus missing ( ROME). 3.Card-mounted ( IEBR).

Diagnosis. This species is most similar to S. lagynos and will run to that species in the key of Naumann (1986). Differences noted in the description above are diagnostic with respect to S. lagynos . Smicromorpha masneri is most easily distinguished from other species of the genus by the shape and sculpture of the petiole (Figs. 4–11) in combination with the size of the transverse lamina at the base of the petiole ( Naumann 1986, his figs. 22, 24). Smicromorpha masneri does not have the strong paired dorsal carinae at the base of the petiole characteristic of S. lagynos (Fig. 10). In addition, S. masneri has distinct tentorial pits, which are absent in S. lagynos . Females of each of the other described species of the Smicromorpha have

Figures 4–ΙΙ. Smicromorpha female petiole. 4–7 lateral view: 4 S. keralensis 5 S. masneri sp. n. 6 S. lagynos 7 S. banksi . 8–ΙΙ dorsal view: 8 S. keralensis 9 S. masneri sp. n. Ι0 S. lagynos ΙΙ S. banksi . dc, dorsal carina.

diagnostic characters not found in S. masneri (see descriptions, illustrations and key in Naumann 1986).

The key in Naumann (1986) can be modified to accommodate S. masneri as follows:

5 Petiole of female ventrally distinctly swollen, less than 3.7 × as long as high, transverse lamina indistinct; antennal clava longer than wide; F1 of female less than 0.7 × as long as F2........................................................................ 6

- Petiole of female ventrally not distinctly swollen, more than 4.0 × as long as high; transverse lamina distinct; antennal clava wider than long; F1 of female 0.8 × as long as F2 ........................................................ S. banksi Naumann

6 Strong paired dorsal carinae present at the base of the petiole (Fig. 10); tentorial pits absent.............................................................. S. lagynos Naumann

- Paired dorsal carinae at the base of petiole absent (Fig. 9); tentorial pits distinct................................................................................... S. masneri sp. n.

Variation. There is variation in the segmentation of the antenna in the type series of S. masneri , specifically concerning the apical flagellomeres. In the holotype, the left antenna is collapsed and the right is slide-mounted. Figure 3 illustrates the right antenna and F6 and F7 are at least partially fused and the differentiation between the articles is most evident by the placement of the multiporus plate sensilla. This fusion of F6 and F7 is also evident in the paratypes but only for the left antennae (paratypes #2 and #3). In paratype #1(both antennae) and paratypes #2 and #3 (both right), F6 and F7 are distinctly separated and F7 is the same length as F6 and only slightly narrower than F6 (Fig. 3, inset). The significance and occurrence of this variation in other species cannot be evaluated at this time. Naumann (1986) was uncharacteristically non-committal about the antennae of females and did not present relative measurements of F6 and F7 (his “clava”) and only illustrated the female antenna of a single species. My notes taken at the ANIC in March 2001 indicate that similar variation occurs in other species of the genus but a much more comprehensive study would be required to fully document and understand this variability. I present these comments primarily as an explanation for Figure 3 and so that future workers will not suffer the anxiety that I have had while trying to reconcile the antennal structure under an assumption of bilateral symmetry.

Notwithstanding the above, the size of the clava and distal flagellar segment (e.g., F6) does appear to have diagnostic value for males and females of the genus ( Naumann 1986, his figs. 3–7). For example, when differentiated from F6, the F7 of S. masneri is distinctly shorter than F7 of S. lagynos , relative to F6.

Biology and rearing notes. The type material of Smicromorpha masneri was obtained by rearing nest pods of Oecophylla smaragdina in a greenhouse where there was no possibility of contamination. The weaver ant nest pods were attached to citrus trees obtained from a local nursery. These trees were examined for possible contamination (e.g., scale insects and aphids) prior to use and the ants and their host trees were the only occupants of the greenhouse. This confirms that these wasps are associated with the Oecophylla smaragdina and that in all likelihood these wasps are primary parasitoids of weaver ants.

Two nest pods – arboreal nest fragments made of leaves and held together with silk from the third-instar ant larvae – were collected at Bach Ma National Park on July 27, 2000 and transported by air in double-sealed containers to Toronto, Canada. The containers were delivered to Tom Mason and Lydia Attard at the Toronto Zoo on July 1; on arrival one nest pod contained only dead ants and the other was assigned #35747. By July 5 new pods were being constructed by the ants and on August 9 Tom Mason observed and later collected a small insect flying in front of one of the new weaver ant pods – the specimen was sent to me for identification. On August 13, three more specimens were caught hovering in the vicinity of the weaver ant pods. These four specimens comprise the type series of S. masneri . Given that the parasitoids were associated with a weaver ant nest in a secure indoor facility and far outside its normal range it is virtually certain that the wasps emerged from the ant nest that was transported to Toronto – and that the type locality is properly indicated as Vietnam. The ant colony survived at the Toronto Zoo for almost a year but no additional Smicromorpha were observed. It is curious that no males were collected but males wouldn’t necessarily be expected hovering around the weaver ant pods, unless they were searching for mating opportunities.