Dolichogenidea finchi Fagan-Jeffries & Austin, 2018

Fagan-Jeffries, Erinn P., Cooper, Steven J. B. & Austin, Andrew D., 2018, Three new species of Dolichogenidea Viereck (Hymenoptera, Braconidae, Microgastrinae) from Australia with exceptionally long ovipositors, Journal of Hymenoptera Research 64, pp. 177-190 : 177

Dolichogenidea finchi Fagan-Jeffries & Austin sp. n.

Figure 2

Material examined.

Holotype ♀: AUSTRALIA, WA, Kariijini NP, Kariijini Dr , 22.5716°S, 118.3072°E; 19-25/iv/2003, C Lambkin & T Weir, malaise in open Eucalyptus grassland, 814 m (WAM: E94085 ) . Paratypes: ♀ WA, Kariijini NP, Weano Gorge Rd, 22°21'19"S, 118°15'00"E; 25/iv/2003 - 15/v/2003, C Lambkin & T Weir, malaise in grassy dry creek Eucalyptus - Acacia scrub, 695 m (WAM: E94086 ) ; ♀ NSW, Wilcannia , 23/xi/1949, E.F. Riek (ANIC: #32 130282) ; ♀ QLD, Binna Burra , Lamington National Park, 29/v/1966, Z. Liepa, at light (ANIC: #32 130284) ; ♀ QLD, Brisbane , vi/1904, RCL Perkins (NHM: #NHMUK010880682) ; ♀ QLD, 3.5 km SW by S of Mt Baird , 15.10°S, 145.07°E; 3-5/v/1981, I.D. Nauman, ex. ethanol, collected at light (ANIC: #32 130286) ; ♀ Vic , 18 km NW by N Omeo, 28/ii/1980, J.C. Cardale, ex alcohol (ANIC: #32 130283) ; ♀ WA, Millstream , 26/x/1970, J.C. Cardale (ANIC: #32 130285) ; ♀ WA, 21 km E by N Yellowdine , 10/x/1981, I.D. Naumann, J.C. Cardale, ex ethanol, on Eucalyptus flowers (WAM: E94087 ) ; ♀ WA, 1 km NNW of Eucla Pass , 31.40°S 128.52°E, 20/v/1984, E.S. Nielson, E.D. Edwards (WAM: E94088 ) .

Diagnosis.

Dolichogenidea finchi can be separated from D. mediocaudata by having a longer ovipositor, smoother T1, and more consistent pale orange colouration of the legs; and from D. xenomorph by absence of a strong sculpturing pattern on the propodeum (Fig. 2d ) and lighter colouration of the lateral metasoma (Fig. 2b ).

Description.

(Female). Colour. Head and body dark; tergites dark, T3 sometimes orange on lateral thirds (Fig. 2a ); S1-3 paler than posterior sternites; antenna dark; coxae (pro-, meso-, metacoxa): dark, dark, dark; femora (pro-, meso-, metafemur): pale/orange, pale/orange, pale/orange; tibiae (pro-, meso-, metatibia): pale/orange, pale/orange, pale/orange anteriorly and subtly darker at basitarsus boundary; tegula and humeral complex pale; pterostigma dark, often with subtle to distinct pale patch at proximal end; fore wing veins pale proximally transitioning to dark distal to pterostigma.

Head. Antennae slightly shorter than body length; body length (head to apex of metasoma): 3.4-4.4 mm; ocular-ocellar line/posterior ocellus diameter: 1.4-1.9; interocellar distance/posterior ocellus diameter: 1.3-2.3.

Mesosoma. Anteromesoscutum densely and evenly punctate; mesoscutellar disc mostly smooth and shining with sparse punctures mostly associated with setae, lateral faces of the mesoscutellum normally smooth and shining to lunules but sometimes with a distinct line of pits or with subtle area of sculpturing posterior to lunules; number of pits in scutoscutellar sulcus: varies from 12 to 22; maximum height of mesoscutellum lunules/maximum height of lateral face of mesoscutellum 0.7-0.8. Propodeum with sparse punctures associated with setae, areola only indicated by smoother area in centre of propodeum and short carinae diverging from centre posterior margin of propodeum.

Fore wing length 3.2-4 mm; length of veins r/2RS 1.5-2.2; length of veins 2RS/2M 1.0-1.7; length of veins 2M/(RS+M)b 0.5-0.8; pterostigma length/width 2.6-3.1.

Legs. Metatibia inner spur length/metabasitarsus length 0.2-0.4.

Metasoma. T1 length/width at posterior margin 1.2-1.8; T1 shape broad, rectangular, almost parallel-sided; T1 mostly smooth with sparse punctures associated with short setae on lateral sides of posterior half; T2 width at posterior margin/length 2.1-3.1; T2 sculpture smooth and shiny, few shallow punctures associated with setae; T2/T3 boundary indistinct and sinuate. T3 smooth and shiny, at least twice as long as T2; hypopygium large with lateral creases, ovipositor sheath length/metatibial length 2.9-3.9.

Male. Unknown.

COI Genbank accession numbers.

MH138733 (Holotype) MH138940 (Paratype WAM: E94086)

Remarks.

It is possible that if more specimens become available and are amenable to DNA sequencing, D. finchi , as described here, will turn out to be a species complex of several closely related species. There is variation in several morphological characters such as subtle differences in the length and shape of the metanotum, the colour of T3, and length of the ovipositor in relation to the metatibia. However, with so few specimens and a lack of molecular data we feel it is more practical at this stage to treat them as one variable species. Further, the COI sequences of the two specimens, sequenced as part of a parallel study ( Fagan-Jeffries et al. in press), are 2.5% divergent, which is above the 2% divergence of the COI barcoding region threshold considered to delimit species of microgastrines in 95% of cases ( Smith et al. 2013).

Etymology.

This species is named for the late grandfather of one of us (EFJ), Alexander Finch, who was a sheep pastoralist near the town of Wilcannia, the locality for one of the paratypes.

Distribution.

This species occurs widely across the continent (Fig. 1 ) and is recorded from WA, Qld, Vic and NSW.

Host.

Whilst the host for this species has not been recorded, two specimens were collected in association with Eucalyptus . As D. xenomorph is the parasitoid of a larva feeding on Eucalyptus , it is a strong possibility that D. finchi also parasitises a Eucalyptus -associated lepidopteran.

Figures

Figure 1. Known distributions of D. xenomorph (blue circles) D. finchi (red squares) and D. mediocaudata (yellow star).

Figure 2. Dolichogenidea finchi (holotype): a metasoma b lateral habitus c dorsal habitus d mesosoma e head.