Sirex tianshanicus

Taxonomy

Family: Siricidae
Subfamily: Siricinae
Genus: Sirex Linnaeus, 1760
Species: Sirex tianshanicus (Semenov, 1921)
Common names: none

Background

Sirex tianshanicus is a rare species known from central Asia (Smith 1978). The name comes from the Tian Shan mountain range (Kazenas and Temreshev 2016).

Diagnostic characteristics

See Sirex for genus-level diagnostic characteristics.

Females:

Males:

May be confused with

Sirex tianshanicus females are similar to S. juvencus and can be distinguished by a slightly longer ovipositor (about 0.75 times length of fore wing) and the green coloration (Benson 1943, Kazenas and Temreshev 2016).

Morphological and geographical variation

none recorded

Host associations

Sirex species feed on trees of Pinaceae and Cupressaceae. Sirex tianshanicus is known from Picea schrenkiana (Asian spruce) (Smith 1978).

Life history

Female Sirex harbor symbiotic basidiomycete fungus in abdominal glands called mycangia. During oviposition, the site is inoculated with the fungus (Amylostereum spp.), which begins to decompose the surrounding wood. Larvae feed on the fungus, and in the process bore galleries through the wood (Schiff et al. 2012).

Larvae are creamy white and grub-like in appearance with a dark head capsule. As with adults, larvae possess a short dorsal horn on the posterior end of the body. The larvae bore galleries into wood, feeding until pupation and subsequent emergence. Throughout this process, the larvae use their horn to pack the tunnel behind them with sawdust. Emergence holes are perfectly circular. The fungal symbiont is carried in specialized organs in female larvae that develop into the mycangia after metamorphosis (Schiff et al. 2012).

This species generally oviposits into dying or damaged trees. The damage inflicted by S. tianshanicus in the forests of the Tien Shan mountain range is minor on its own, but in conjunction with human-inflicted tree damage and other pest pressure, can lead to the death of the tree (Kazenas and Temreshev 2016).

The flight period of S. tianshanicus is June through September (Kazenas and Temreshev 2016).

Distribution

World: Sirex tianshanicus is recorded in the Tian Shan mountainous regions of western China, Kyrgyzstan, and Kazakhstan (Smith 1978, Kazenas and Temreshev 2016).

North America: not recorded

Map data from: GBIF.org (26 June 2019) GBIF Occurrence Download Sirex tianshanicus

Details about data used for maps can be found here.

Specimens of this species not available for imaging.