Nannochoristidae

Nannochoristidae
Temporal range: Middle Jurassic–Recent
Nannochorista philpotti
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Mecoptera
Family: Nannochoristidae
Tillyard, 1917
Genera

See text

Nannochoristidae is a family of scorpionflies with many unusual traits. It is a tiny, relict family with a single extant genus, Nannochorista, with eight species occurring in New Zealand, southeastern Australia, Tasmania, Argentina and Chile. Due to the group's distinctiveness from other scorpionflies, it is sometimes placed in its own order, the Nannomecoptera. Some studies have placed them as the closest living relatives of fleas.[1] Most mecopteran larvae are eruciform, or shaped like caterpillars. Nannochoristid larvae, however, are elateriform, and have elongated and slender bodies. The larvae are aquatic, which is unique among mecopterans. The larvae are predatory, hunting on the beds of shallow streams, primarily on the larvae of aquatic Diptera like chironomids.[2] The adults are thought probably to be adapted to liquid feeding, likely on flower nectar and/or the juice of fruits. Adults of Australian and South American species are often found in habitats like the edges of streams, lakes, as well as montane bogs. Australian species have been observed visiting the foliage and flowers of Leptospermum (tea trees).[3]

Fossils indicate that Nannochoristidae formerly had a wider distribution, being present in the Northern Hemisphere during the Jurassic and Early Cretaceous.[4]

Some research suggests the nannochoristids are the only holometabolous insects with true larval compound eyes.[5] All other eyed larvae have stemmata, which are structurally different from adult compound eyes with ommatidia. This is unusual, since most adult features are present as imaginal discs in larvae and not formed until pupation. The presence of compound eyes in nannochoristid larvae suggests the timing of the development of adult features can be initiated earlier in development, which has important implications for insect evolutionary development.

  1. ^ Cite error: The named reference :0 was invoked but never defined (see the help page).
  2. ^ Fraulob, Maximilian; Wipfler, Benjamin; Hünefeld, Frank; Pohl, Hans; Beutel, Rolf G. (March 2012). "The larval abdomen of the enigmatic Nannochoristidae (Mecoptera, Insecta)". Arthropod Structure & Development. 41 (2): 187–198. doi:10.1016/j.asd.2011.11.001. PMID 22309703.
  3. ^ Palmer, Christopher (2010). "Diversity of feeding strategies in adult Mecoptera". Terrestrial Arthropod Reviews. 3 (2): 111–128. doi:10.1163/187498310x519716. ISSN 1874-9828.
  4. ^ LIU, NAN; Zhao, Yunyun; REN, DONG (2010-04-07). "Two new fossil species of Itaphlebia (Mecoptera: Nannochoristidae) from Jiulongshan Formation, Inner Mongolia, China". Zootaxa. 2420 (1): 37. doi:10.11646/zootaxa.2420.1.3. ISSN 1175-5334.
  5. ^ Melzer, R. R.; H. F. Paulus & N. P. Kristensen (1994). "The larval eye of nannochoristid scorpionflies (Insecta, Mecoptera)". Acta Zoologica. 75 (3): 201–208. doi:10.1111/j.1463-6395.1994.tb01207.x.