Pergidae

Taxonomy

Superfamily: Tenthrediniodea
Family: Pergidae
Family common name: pergid sawflies
Subfamilies: Acordulecerinae, Conocoxinae, Euryinae, Loboceratinae, Parasyzygoniinae, Perginae, Pergulinae, Perreyiinae, Philomastiginae, Phylacteophaginae, Pterygophorinae, Pteryperginae, Styracotechyinae, Syzygoniinae

Background

The family Pergidae is common and diverse in Australia and South America (Smith and Middlekauff 1987Smith and Middlekauff 1987:
Smith DR and Middlekauff WW. 1987. Suborder Symphyta. In: Stehr FW ed. Immature Insects. Kendall/Hunt Publishing Company. Vol. 1: 754 pp.). The family includes several subfamilies, but only one genus is represented in North America: Acordulecera. Adults are easily recognized by a small-medium body size, about 3–10 mm, and the 3-segmented flagellumflagellum:
the third section of the antennae that includes all the segments beyond the pedicel; segments of the flagellum are known as flagellomeres
(Goulet 1992Goulet 1992:
Goulet H. 1992. The genera and subgenera of the sawflies of Canada and Alaska: Hymenoptera. Symphyta. The insects and arachnids of Canada. Part 20. Agriculture Canada Publication.). Acordulecera feed on deciduousdeciduous:
describing a tree that drops its foliage once a year and then re-grows it; often senescence occurs before winter and re-growth occurs in the spring
tree species and are generally not of economic importance (Smith and Middlekauff 1987Smith and Middlekauff 1987:
Smith DR and Middlekauff WW. 1987. Suborder Symphyta. In: Stehr FW ed. Immature Insects. Kendall/Hunt Publishing Company. Vol. 1: 754 pp.).

Diversity

Pergidae includes 60 genera and 442 species worldwide. A single genus and 13 species are NearcticNearctic:
describing the region of the Northern Hemisphere that includes North America south through northern Mexico
in distribution (Taeger et al. 2018Taeger et al. 2018:
Taeger A, Liston AD, Prous M, Groll EK, Gehroldt T, and Blank SM. 2018. ECatSymmdash;Electronic World Catalog of Symphyta (Insecta, Hymenoptera). Program version 5.0 (19 Dec 2018), data version 40 (23 Sep 2018). Senckenberg Deutsches Entomologisches Institut (SDEI), Muuml;ncheberg. https://sdei.de/ecatsym/ Accessed: 28 Jan 2020.).

North American genera

Acordulecera

Diagnostic characteristics

• pronotum pronotum:
  the anterodorsal part of the thorax, often situated posterior to the head
  medially constricted as seen from above (Goulet 1992Goulet 1992:
  Goulet H. 1992. The genera and subgenera of the sawflies of Canada and Alaska: Hymenoptera. Symphyta. The insects and arachnids of Canada. Part 20. Agriculture Canada Publication.)
• propleuron propleuron:
  a lateral sclerite located between the pronotum and episternum near the anterior of the body
  short ventrally (Goulet 1992Goulet 1992:
  Goulet H. 1992. The genera and subgenera of the sawflies of Canada and Alaska: Hymenoptera. Symphyta. The insects and arachnids of Canada. Part 20. Agriculture Canada Publication.)
• 2 fore tibialfore tibia:
  the tibia of the fore leg
  spurs present (Goulet 1992Goulet 1992:
  Goulet H. 1992. The genera and subgenera of the sawflies of Canada and Alaska: Hymenoptera. Symphyta. The insects and arachnids of Canada. Part 20. Agriculture Canada Publication.)
• 6 antennal segments; 4 flagellomeres (Goulet 1992Goulet 1992:
  Goulet H. 1992. The genera and subgenera of the sawflies of Canada and Alaska: Hymenoptera. Symphyta. The insects and arachnids of Canada. Part 20. Agriculture Canada Publication.)
• notaulus notaulus:
  one of a pair of diverging furrows on the mesoscutum
  not outlined (Goulet 1992Goulet 1992:
  Goulet H. 1992. The genera and subgenera of the sawflies of Canada and Alaska: Hymenoptera. Symphyta. The insects and arachnids of Canada. Part 20. Agriculture Canada Publication.)
• antennae filiformfiliform:
  generally slender and of even diameter throughout
  (Goulet 1992Goulet 1992:
  Goulet H. 1992. The genera and subgenera of the sawflies of Canada and Alaska: Hymenoptera. Symphyta. The insects and arachnids of Canada. Part 20. Agriculture Canada Publication.)
• tergite tergite:
  a sclerotized segment of the tergum
  1 laterally fused to metapleuronmetapleuron:
  the posterior lateral part of the thorax including the metepimeron and metepisternum
  (Goulet 1992Goulet 1992:
  Goulet H. 1992. The genera and subgenera of the sawflies of Canada and Alaska: Hymenoptera. Symphyta. The insects and arachnids of Canada. Part 20. Agriculture Canada Publication.)
• forewing veinvein:
  a tube-like, often darkened, structure on the wings
  2r absent (Goulet 1992Goulet 1992:
  Goulet H. 1992. The genera and subgenera of the sawflies of Canada and Alaska: Hymenoptera. Symphyta. The insects and arachnids of Canada. Part 20. Agriculture Canada Publication.)

Host associations

In North America, Pergidae feed on plants of the families Juglandaceae and Fagaceae (Smith and Middlekauff 1987Smith and Middlekauff 1987:
Smith DR and Middlekauff WW. 1987. Suborder Symphyta. In: Stehr FW ed. Immature Insects. Kendall/Hunt Publishing Company. Vol. 1: 754 pp.).

May be confused with

Sawflies in this family are similar in form to families in the superfamily Tenthredinoidea: Diprionidae, Argidae, and Tenthredinidae. Pergidae can be distinguished by the number of antennal segments (Goulet 1992Goulet 1992:
Goulet H. 1992. The genera and subgenera of the sawflies of Canada and Alaska: Hymenoptera. Symphyta. The insects and arachnids of Canada. Part 20. Agriculture Canada Publication.).

Life history

Pergidae in North America are external leaf feeders that skeletonize leaves (Smith and Middlekauff 1987Smith and Middlekauff 1987:
Smith DR and Middlekauff WW. 1987. Suborder Symphyta. In: Stehr FW ed. Immature Insects. Kendall/Hunt Publishing Company. Vol. 1: 754 pp.).

Distribution

World: Pergidae is most diverse in the Southern Hemisphere and occurs in North America, Australia, New Guinea, and South America (Goulet 1992Goulet 1992:
Goulet H. 1992. The genera and subgenera of the sawflies of Canada and Alaska: Hymenoptera. Symphyta. The insects and arachnids of Canada. Part 20. Agriculture Canada Publication.).

North America: Acordulecera occurs in Canada, the United States, the Caribbean Islands, and Central America (Smith 2006aSmith 2006a:
Smith DR. 2006a. Checklist of the Pergidae (Hymenoptera: Symphyta) of the Western Hempisphere, with a new genus and two species. Recent sawfly research: synthesis and prospects: 1-3.).