Agathidinae
Agathidinae is a subfamily of braconid parasitoid wasps. Some species have been used in biological control programs.
Description
Agathidines are among the larger braconids, and diurnal members of this subfamily are often brightly patterned. They belong to the noncyclostome group. Several genera, such as Agathis, Cremnops and Disophrys, are characterized by elongate genae.Agithidines can be recognized by the following combinations of features: forewing veins M + CU not tubular in basal third or more, forewing vein RS complete to the wing margin,'' occipital carina absent, and second submarginal cell of forewing usually present
Distribution
They are found worldwide, but are more diverse in the tropics. However, some genera such as Agathis and Earinus are more speciose in temperate regions.Biology
Most Agathidines are solitary koinobiont endoparasitoids of concealed Lepidoptera larvae. However, the tribe Disophrini attacks free living Lepidoptera larvae. The tribes Agathidini and Earinini attack the first and second instar larvae of their hosts, contrasting with the Disophrini, which attack later instars, as well as the Cremnoptini, which parasitize every larval stage. Most species are diurnal, but many Disophrini are nocturnal, with pale coloration and enlarged ocelli. Most species attack semi-concealed hosts, like leaf-rollers.Agathidines have three larval instars. They likely seek out and kill competitors as first instars. As final instars, they emerge from their host caterpillar, feed externally, then spin their cocoons. Temperate species overwinter in their hosts during their first instar.
Some species, such as Earinus elator, seek out hosts very early in the year, "about the time of bud-burst of their hosts' host plants." In relation to this, they have evolved to complete their metamorphosis before winter so they can more easily seek out hosts early. To prevent their freezing from their nitrogen-filled Meconium onward, they secrete a goo rich in glycerol and fatty acids over the waste. This reduces the freezing point of the water in the waste, preventing ice formation.
Most tropical species are brightly colored and are involved in mimicry.
Studies of the species Alabagrus texanus have found that males that arrive early to a site where females recently emerged from were often successful, but the very young and very old males were always unsuccessful. Males also had short-term memory regarding sites of female emergence.
Agathidines have been noted to be more abundant in ecosystems where fluids are harder to obtain. Many have concealed nectar extraction adaptations that make them more adapted to gaining nectar from flowers, "perhaps particularly from Asteraceae." These CNEAs include elongate malar regions, galea, glossa, and maxillary palps that form a tube. These elongate mouthparts have independently evolved in the subfamily six times.
Agathis clavatus has been found to practice the mating system of males searching for females at feeding sites. This strategy is hardly found in Ichneumonoidea.
Taxonomy and phylogeny
The first attempt at a tribal arrangement for Agathidinae consisted of 2 tribes, Agathidini and Microdini. Sharkey revised the tribes in 1992 and considered 5 tribes, adding Cremnoptini, Disophrini, and Earini. The Microdini, then treated as Eumicrodini, was synonymized under Agathidini by Simbolotti and van Achterberg in 1999 to render 4 tribes. Phylogenetic analysis by Sharkey and Chapman in 2017 revealed that 4 tribes were insufficient and instead divided the subfamily into 7 tribes. They further found that the genera Asperagathis, Bassus, and Zosteragathis were not monophyletic. One problematic species, the Nearctic Bassus annulipes, was found to represent a complex of species. Further, Bassus annulipes was rendered under the tribe Lytopylini while the Old World species fell under Agathidini.Relationship with humans
Agathidines have been used for biological pest control. Notable examples include Agathis pumila for the western larch case-bearer, Alabagrus stigma for the sugarcane borer, and Bassus unicoloratus and Agathis gibbosa for the potato tuberworm. Other species play important roles in their native ecosystems to suppress forestry pests, such as Bassus tumidulus which controls the population of Gypsonoma aceriana.Genera
The 63 genera placed here include:Tribe [Agathidini] Haliday, 1833
Aerophilus Szépligeti, 1902Agathacrista Sharkey, 2013Agathigma Sharkey, 2017Agathis Latreille, 1804Alabagrus Enderlein, 1920Aphelagathis Sharkey, 2015Asperagathis Sharkey, 2017Bassus Fabricius, 1804 Braunsia Kriechbaumer, 1894Camptothlipsis Enderlein, 1920Chimaeragathis Sharkey, 2017Cymagathis Sharkey, 2017Gyragathis van Achterberg & Long, 2010Ischnagathis Cameron, 1909Leuroagathis Sharkey, 2017Liragathis Sharkey, 2017Neothlipsis Sharkey, Parys & Clutts, 2011Pharpa Sharkey, 1986Plesiocoelus van Achterberg, 1990Pneumagathis Sharkey, 2015Scabagathis Sharkey, 2017Trachagathis Viereck, 1913Trochantagathis Sharkey, 2017Xanthagathis Sharkey, 2017Zamicrodus Viereck, 1912Zosteragathis Sharkey, 2017Tribe [Agathirsini] Sharkey, 2017
Agathirsia Westwood, 1882Crassomicrodus Ashmead, 1900Gelastagathis Sharkey, 2015Marjoriella Sharkey, 1983Tribe [Cremnoptini] Sharkey, 1992
Cremnops Foerster, 1862Cremnoptoides van Achterberg & Chen, 2004Hyrtanommatium Enderlein, 1920Labagathis Enderlein, 1920Megalagathis Schulz, 1906Mesoagathis Cameron, 1905Zacremnops Sharkey & Wharton, 1985Tribe [Disophrini] Sharkey, 1992
Coccygidium Saussure, 1892Coronagathis van Achterberg & Long, 2010Disophrys Förster, 1863Euagathis Szépligeti, 1900Gyrochus Enderlein, 1920Hemichoma Enderlein, 1920Hypsostypos Baltazar, 1963Liopisa Enderlein, 1920Macroagathis Szépligeti, 1908Monophrys van Achterberg, 1988Oreba Cameron, 1900Pelmagathis Enderlein, 1920Protroticus van Achterberg, 1988Troticus Brullé, 1846Zelodia van Achterberg, 2010Zelomorpha Ashmead, 1900Tribe [Earinini] Sharkey, 1992
Chilearinus Sharkey, 2022Earinus Wesmael, 1837Tribe [Lytopylini] Sharkey, 2017
Amputoearinus Sharkey, 2006Austroearinus Sharkey, 2006Lytopylus Förster, 1862Sesioctonus Viereck, 1912Smithagathis Sharkey, 2017Tribe [Mesocoelini] Achterberg, 1990
Aneurobracon Brues, 1930 Mesocoelus Schulz, 1911 Therophilus Wesmael, 1837- Undescribed genus