Sirex mongolorum

Taxonomy

Family: Siricidae
Subfamily: Siricinae
Genus: Sirex Linnaeus, 1760
Species: Sirex mongolorum (Semenov & Gussakovskij, 1935)
Common names: none

Background

Sirex mongolorum is a rare, completely dark species that is known only from Mongolia and eastern Russia (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. It was difficult to translate, and the translating authors and subsequent researchers have been unable to confirm their accuracy.

Females:

• head and body dark blue-black (Semenov and Gussakovskij 1935Semenov and Gussakovskij 1935:
  Semenov A and Gussakovskij VV. 1935. Siricides nouveaux ou peu connus de la fauna paleacute;arctique (Hymenoptera). Annales de la Socieacute;teacute; Entomologique de France 104: 117-126.)
• antennae black (Semenov and Gussakovskij 1935Semenov and Gussakovskij 1935:
  Semenov A and Gussakovskij VV. 1935. Siricides nouveaux ou peu connus de la fauna paleacute;arctique (Hymenoptera). Annales de la Socieacute;teacute; Entomologique de France 104: 117-126.)
• coxae and femorafemur:
  the third segment of the leg between the trochanter and the tibia
  dark blue (Semenov and Gussakovskij 1935Semenov and Gussakovskij 1935:
  Semenov A and Gussakovskij VV. 1935. Siricides nouveaux ou peu connus de la fauna paleacute;arctique (Hymenoptera). Annales de la Socieacute;teacute; Entomologique de France 104: 117-126.)
• tibiae and tarsitarsus:
  the fifth and last segment of the leg
  yellowish-brown; tibiaetibia:
  the fourth segment of the leg, between the femur and the tarsus
  slightly darkened at the basebase:
  the beginning or most proximal area of any structure
  (Semenov and Gussakovskij 1935Semenov and Gussakovskij 1935:
  Semenov A and Gussakovskij VV. 1935. Siricides nouveaux ou peu connus de la fauna paleacute;arctique (Hymenoptera). Annales de la Socieacute;teacute; Entomologique de France 104: 117-126.)
• fore wing fore wing:
  the anterior wing of each pair of wings; usually the largest wing of the pair
  hyaline and slightly darkened apically (Semenov and Gussakovskij 1935Semenov and Gussakovskij 1935:
  Semenov A and Gussakovskij VV. 1935. Siricides nouveaux ou peu connus de la fauna paleacute;arctique (Hymenoptera). Annales de la Socieacute;teacute; Entomologique de France 104: 117-126.)
• cornus cornus:
  a pointed horn-like process on the apical end of the abdomen in Siricidae sawflies; on tergite 10 in females, sternite 9 in males
  short; ovipositorovipositor:
  the female organ that deposits eggs and is used to drill into plant tissue, located at the apex of the abdomen, made up of the lance and lancet
  not much longer, also short (Semenov and Gussakovskij 1935Semenov and Gussakovskij 1935:
  Semenov A and Gussakovskij VV. 1935. Siricides nouveaux ou peu connus de la fauna paleacute;arctique (Hymenoptera). Annales de la Socieacute;teacute; Entomologique de France 104: 117-126.)
• mesoscutum mesoscutum:
  the central and dorsal portion of the thorax between the scutellum and postnotum
  densely punctured (Semenov and Gussakovskij 1935Semenov and Gussakovskij 1935:
  Semenov A and Gussakovskij VV. 1935. Siricides nouveaux ou peu connus de la fauna paleacute;arctique (Hymenoptera). Annales de la Socieacute;teacute; Entomologique de France 104: 117-126.)
• third antennal segment twice as long as fourth (Semenov and Gussakovskij 1935Semenov and Gussakovskij 1935:
  Semenov A and Gussakovskij VV. 1935. Siricides nouveaux ou peu connus de la fauna paleacute;arctique (Hymenoptera). Annales de la Socieacute;teacute; Entomologique de France 104: 117-126.)

Male S. mongolorum is unknown.

May be confused with

The female Sirex mongolorum can be distinguished from S. imperialis by the mostly light-colored legs (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). The third antennal segment is relatively longer in S. mongolorum than in S. ermak and S. noctilio (Semenov and Gussakovskij 1935Semenov and Gussakovskij 1935:
Semenov A and Gussakovskij VV. 1935. Siricides nouveaux ou peu connus de la fauna paleacute;arctique (Hymenoptera). Annales de la Socieacute;teacute; Entomologique de France 104: 117-126.).

Morphological and geographical variation

none recorded

Host associations

Sirex species feed on trees of Pinaceae and Cupressaceae. Sirex mongolorum is known from Picea spp. (spruce), Larix sibirica (Siberian larch), Larix (larch), Pinus pinea (stone pine), and Pinus spp. (pine) (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.).

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. mongolorum is unknown.

Distribution

World: Sirex mongolorum is recorded in the mountains of Kentii, Mongolia and the city of Chita in eastern Russia (Semenov and Gussakovskij 1935Semenov and Gussakovskij 1935:
Semenov A and Gussakovskij VV. 1935. Siricides nouveaux ou peu connus de la fauna paleacute;arctique (Hymenoptera). Annales de la Socieacute;teacute; Entomologique de France 104: 117-126., 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

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

Details about data used for maps can be found here.