Sirex vates

Taxonomy

Family: Siricidae
Subfamily: Siricinae
Genus: Sirex Linnaeus, 1760
Species: Sirex vates Mocsáry, 1881
Common names: none

Background

Sirex vates is a rare black and yellowish-brown species from China (Smith 1978Smith 1978:
Smith DR. 1978. Suborder Symphyta (Xyelidae, Parachexyelidae, Parapamphiliidae, Xyelydidae, Karatavitidae, Gigasiricidae, Sepulcidae, Pseudosiricidae, Anaxyelidae, Siricidae, Xiphydriidae, Paroryssidae, Xyelotomidae, Blasticotomidae, Pergidae). Hymenopterorum Catalogus 14: 1-193.).

Diagnostic characteristics

See Sirex for genus-level diagnostic characteristics.

The following characters are taken from the short, original description written in Latin (Mocsáry 1881). It was difficult to translate, and the translating authors and subsequent researchers have been unable to confirm their accuracy.

Females:

• abdominal tergitetergite:
  a sclerotized segment of the tergum
  1 blue, 2–7 dull yellowish-brown, and 8–9 shining and black (Mocsáry 1881)
• fore tibia fore tibia:
  the tibia of the fore leg
  and tarsustarsus:
  the fifth and last segment of the leg
  reddish-brown; remaining tibiaetibia:
  the fourth segment of the leg, between the femur and the tarsus
  and tarsitarsus:
  the fifth and last segment of the leg
  black (Moscáry 1881)
• fore wing fore wing:
  the anterior wing of each pair of wings; usually the largest wing of the pair
  hyaline and/or dark bands near the center and at apexapex:
  the end or most distal area of any structure
  of wing (Mocsáry 1881)
• venation venation:
  the network of veins on a wing
  black; costacosta:
  the robust vein on the anterior margin of the wing; vein C
  brown (Mocsáry 1881)
• antenna antenna:
  the sensory organ emerging from the front of the head, usually between the compound eyes and above the clypeus; includes the flagellum, scape and pedicel
  with 21 segments (Mocsáry 1881)

Male S. vates is not known.

May be confused with

Female S. vates can be distinguished from similar species S. piceus by the clear fore wingfore wing:
the anterior wing of each pair of wings; usually the largest wing of the pair
(Xiao and Wu 1983Xiao and Wu 1983:
Xiao G and Jian W. 1983. The siricid wood wasps of China (Hymenoptera, Symphyta). Scientia Silvae Sinicae Memoirs of Forest Entomology 8: 1-29.), and from S. imperialis by the dull, non-metallic abdomenabdomen:
the third and last segment of an insect's body; in sawflies this is usually made up of 11 segments (segments 9 and 10 often fused)
(Benson 1943Benson 1943:
Benson RB. 1943. Studies in Siricidae, especially of Europe and southern Asia (Hymenoptera, Smphyta). Bulletin of Entomological Research 34 (1): 27-51. https://doi.org/10.1017/S0007485300023464).

Morphological and geographical variation

none recorded

Host associations

unknown

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. LarvaeLarva:
the immature stage of holometabolous insects
feed on the fungus, and in the process bore galleries through the wood (Schiff et al. 2012Schiff et al. 2012:
Schiff NM, Goulet H, Smith DR, Boudreault C, Wilson AD, and Scheffler BE. 2012. Siricidae (Hymenoptera: Symphyta: Siricoidea) of the Western Hemisphere. Canadian Journal of Arthropod Identification 21: 1-305.).

Larvae are creamy white and grub-like in appearance with a dark head capsule. As with adults, larvaelarva:
the immature stage of holometabolous insects
possess a short dorsaldorsal:
of or on the top surface of the body or structure
horn on the posterior end of the body. The larvaelarva:
the immature stage of holometabolous insects
bore galleries into wood, feeding until pupation and subsequent emergence. Throughout this process, the larvaelarva:
the immature stage of holometabolous insects
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 larvaelarva:
the immature stage of holometabolous insects
that develop into the mycangia after metamorphosis (Schiff et al. 2012Schiff et al. 2012:
Schiff NM, Goulet H, Smith DR, Boudreault C, Wilson AD, and Scheffler BE. 2012. Siricidae (Hymenoptera: Symphyta: Siricoidea) of the Western Hemisphere. Canadian Journal of Arthropod Identification 21: 1-305.).

The specific biology of S. vates is unknown.

Distribution

World: Sirex vates is found in northern China and in the province Sichuan (Mocsáry 1881, Smith 1978Smith 1978:
Smith DR. 1978. Suborder Symphyta (Xyelidae, Parachexyelidae, Parapamphiliidae, Xyelydidae, Karatavitidae, Gigasiricidae, Sepulcidae, Pseudosiricidae, Anaxyelidae, Siricidae, Xiphydriidae, Paroryssidae, Xyelotomidae, Blasticotomidae, Pergidae). Hymenopterorum Catalogus 14: 1-193.).

North America: not recorded

No specific locality data was available for mapping the range of this species at the time of publication.