Sirex noctilio Fabricius, 1793

John M. Leavengood, Jr. & Smith, Trevor Randall, 2013, The Siricidae (Hymenoptera: Symphyta) of Florida, Insecta Mundi 2013 (309), pp. 1-16 : 11-13

Sirex noctilio Fabricius, 1793

( Fig. 22-27 )

Diagnosis. Females of S. noctilio have an entirely bluish-black abdomen, entirely reddish-yellow legs, an ovipositor which is shorter than the forewing, and black antennae. Sirex longicauda and S. areolatus are separated by having longer ovipositors. Sirex edwardsii has black legs while S. juvencus and S. cyaneus have orangish tarsi. Sirex behrensii and S. nigricornis are distinguished by the presence of orange on the abdomen. Sirex varipes is quite similar, but has more clear wings and the orange legs often seem to have an “additional” surfacing of blue on some segments. Males of S. noctilio have black antennae, entirely orange front and middle legs, orange metafemora (the rest of the hind leg black), and the abdomen mostly orange with black basal and apical segments (the apical black often reduced to only dorsal or ventral expression). Sirex juvencus is distinguished by its basally pale antennae. Sirex edwardsii , S. areolatus and S. longicauda have entirely black hind legs. Sirex cyaneus , S. nigricornis , S. varipes and S. behrensii are separated by their abdomens, which are only basally black.

Natural history. Various Pinus species (e.g., white, red, jack, Scots, lodgepole, ponderosa) are hosts for S. noctilio ( Dodds and de Groot 2012) . Some rare host records include Abies , Larix , and Pseudotsuga menziesii (Mirbel) Franco (Pinaceae) ( Smith and Schiff 2002; Schiff et al. 2006), but emergence from non-pine hosts is not expected. Sirex noctilio is a major pest of P. radiata in New Zealand and Australia and is now a threat to this species in South Africa and South America. The major (threatened) pine plantations in South America are Loblolly Pine ( Pinus taeda ) and Mexican Weeping Pine ( Pinus patula ) in South Africa ( Dodds et al. 2010; Dodds and de Groot 2012).

Adults and larvae harbor Amylostereum areolatum , a fungal symbiont ( Smith and Schiff 2002).

Distribution. While there are no specimens of S. noctilio in the FSCA, nor any intercepted in Florida ports, this species has been included due to its invasiveness and recent detection in North America.

Sirex noctilio is native to Asia, northern Africa, and Europe. It is adventive in Australia, New Zealand, South Africa, South America and North America ( Morgan 1968). In North America it occurs in Michigan, New York, Ohio, Pennsylvania, Vermont, Quebec and Ontario ( Dodds and de Groot 2012; Schiff et al. 2006; USDA 2010). No specimens have been collected in Florida.

Figures

Figures 22-27. 22-24) Sirex noctilio female. 22) dorsal habitus. 23) Lateral habitus. 24) Wings. 25-27) Sirex noctilio male. 25) Dorsal habitus. 26) Lateral habitus. 27) Wings.