Ogcodes is a cosmopolitan genus of small-headed flies in the family Acroceridae. About 90 species have been described for the genus. It is the most common and speciose genus in its family. These flies are endoparasitoids of ground-dwelling entelegyne spiders.
Characteristics Flies in this genus can be distinguished from other genera in the family Acroceridae by the following combination of characteristics: Antennae positioned on the ventral surface of the head, slightly above the mouth Tibiae lacking apical spurs Eyes always holoptic Short, rod-like antennal flagellum Mouthparts hidden by a membrane Reduced wing venation
Adult Ogcodes are small to medium in size, with rounded heads and abdomens. They are often brown or black in color, with a pale horizontal band at the posterior edge of each abdominal tergite.
Life History Soon after mating, females lay their eggs around dead twigs. These eggs are brown or black in color, and usually under 0.35 millimeters in length. Larvae are endoparasitoids in spiders. Upon emerging, planidial larvae wait to come in contact with a host spider. If a host is not found, the larvae can move to nearby sites by springing into the air or moving similarly to an inchworm. If a host is found, the larva will typically enter it through the abdomen, or occasionally through the intersegmental membranes of the legs. Upon attaching to the inside of the host, the larva will molt twice at a rate that depends on the developmental pace of the host. The site of attachment is in an air pocket between the lamellae of the spider's book lungs. The third-instar larva will consume most of the host spider’s internal contents, then emerge by making a hole along the host’s epigastric furrow. Evidence that acrocerid flies deliberately influence host behavior is limited, but flies in this genus have been observed emerging shortly after their hosts create webbing and clinging to the new webbing using adhesives on their bodies. One to three days after emerging, the larva pupates. Adults can be encountered around dead twigs, or in grassy, wet areas. They have not been observed feeding, though it is possible that the oral membrane in place of functioning mouthparts may be used to collect moisture from the air. Adults are thought to live for three to four weeks at maximum in nature.
Hosts Larval Ogcodes have been documented developing in spiders from the following taxonomic families: Araneidae Theridiidae Lycosidae Agelenidae Psechridae Amaurobiidae Oxyopidae Anyphaenidae Clubionidae Gnaphosidae Philodromidae Thomisidae Salticidae
Like many acrocerids, planidial Ogcodes tend to target hosts that wander or build webs on the ground. Several species within the genus can develop in spiders from three or more different taxonomic families, namely O. adaptus, O. dispar, O. eugonatus, and O. pallidipennis.
Distribution Ogcodes as a whole is cosmopolitan in distribution. Species richness in Ogcodes is highest in Australia and the Nearctic and Palearctic regions. Species in this genus have not been collected from deserts and certain islands, such as Madagascar and Iceland. The majority of species are found in only one geographic region, with the exceptions of O. pallidipennis, O. dispar, and O. guttatus. Alongside Pterodontia, Ogcodes is one of the two acrocerid genera present in every zoogeographic region.
Taxonomy Ogcodes is the only extant genus within the subfamily Ogcodinae. Based on its morphology, the genus was previously placed within Acrocerinae. While many species in Acrocerinae target haplogyne spiders, not a single species in Ogcodes does. Despite sharing morphological characteristics with the acrocerid genus Pterodontia, such as having antennae located on the ventral surface of the head and reduced mouthparts, molecular data indicates that these two genera are not particularly closely related.
Subgenera and species The genus is split into three subgenera: Ogcodes, Protogcodes and Neogcodes. Ogcodes is cosmopolitan in distribution, Protogcodes is endemic to Australia, and Neogcodes is restricted to the Nearctic.
Subgenus Ogcodes Latreille, 1796
Ogcodes acroventris Nartshuk, 1982 Ogcodes adaptatus Schlinger, 1960 Ogcodes alluaudi Becker, 1914 Ogcodes angustimarginatus Brunetti, 1920 Ogcodes asiaticus Nartshuk, 1975 Ogcodes argentinensis Schlinger, 1960 Ogcodes argigaster Schlinger, 1960 Ogcodes armstrongi Paramonov, 1957 Ogcodes ater White, 1915 Ogcodes basalis (Walker, 1852) Ogcodes bigoti Nartshuk, 1982 Ogcodes boharti Schlinger, 1960 Ogcodes borneoensis Schlinger, 1971 Ogcodes borealis Cole, 1919 Ogcodes brasilensis Schlinger, 1960 Ogcodes brunneus (Hutton, 1881) Ogcodes caffer Loew, 1857 Ogcodes canadensis Schlinger, 1960 Ogcodes canberranus Paramonov, 1957 Ogcodes castaneus Brunetti, 1926 Ogcodes chilensis Sabrosky, 1945 Ogcodes cingulatus Erichson, 1840 Ogcodes clavatus Becker, 1909 Ogcodes coffeatus Speiser, 1920 Ogcodes colei Sabrosky, 1948 Ogcodes colombiensis Schlinger, 1960 Ogcodes congoensis Brunetti, 1926 Ogcodes consimilis Brunetti, 1926 Ogcodes costalis (Walker, 1852) Ogcodes crassitibialis Brunetti, 1926 Ogcodes croucampi Barraclough, 1997 Ogcodes deserticola Paramonov, 1957 Ogcodes diligens Osten Sacken, 1877 Ogcodes dispar (Macquart, 1855) Ogcodes distinctus Brunetti, 1926 Ogcodes doddi Wandolleck, 1906 Ogcodes dusmeti Arias, 1920 Ogcodes esakii Ôuchi, 1942 Ogcodes etruscus Griffini, 1896 Ogcodes eugonatus Loew, 1872 †Ogcodes exotica Grimaldi, 1995 Ogcodes flavescens White, 1915 Ogcodes floridensis Sabrosky, 1948 Ogcodes formosus Loew, 1873 Ogcodes fortnumi Westwood, 1876 Ogcodes fratellus Brunetti, 1926 Ogcodes fraternus Brunetti, 1926 Ogcodes froggatti Schlinger in Schlinger & Jeffries, 1989 Ogcodes fumatus Erichson, 1846 Ogcodes fuscus Brunetti, 1912 Ogcodes gibbosus (Linnaeus, 1758) Ogcodes glomerosus Paramonov, 1957 Ogcodes gressiti Schlinger, 1971 Ogcodes guttatus Costa, 1854 Ogcodes hennigi Schlinger, 1960 Ogcodes hirtus Sack, 1936 Ogcodes hungaricus (Szilády, 1941) Ogcodes ignavus Westwood, 1876 Ogcodes insignis Brunetti, 1926 Ogcodes jacobaeus (Philippi, 1871) Ogcodes jacutensis Pleske, 1930 Ogcodes javanus De Meijere, 1924 Ogcodes kunkunche Barahona-Segovia in Barahona-Segovia et al., 2020 Ogcodes kuscheli Sabrosky, 1951 Ogcodes lautereri Chvála, 1980 Ogcodes leptisoma Schlinger, 1960 Ogcodes lineatus Brunetti, 1926 Ogcodes longicolus Schlinger, 1971 Ogcodes luzonensis Schlinger, 1971 Ogcodes lucidus Paramonov, 1957 Ogcodes maai Schlinger, 1971 Ogcodes marginifasciatus Brunetti, 1926 Ogcodes melampus Loew, 1872 Ogcodes merens Nartshuk, 1982 Ogcodes neavei Brunetti, 1926 Ogcodes niger Cole, 1919 Ogcodes nigrinervis White, 1915 Ogcodes nigripes (Zetterstedt, 1838) Ogcodes nigritarsis Shiraki, 1932 Ogcodes nitens (Hutton, 1901) Ogcodes nyasae Brunetti, 1926 Ogcodes obscuripes Chvála, 1980 Ogcodes orientalis Schlinger, 1960 Ogcodes ottuc Nartshuk, 1982 Ogcodes pallidipennis Loew, 1865 Ogcodes pallipes Latreille in Olivier, 1812 Ogcodes pamiricus Nartshuk, 1982 Ogcodes philippinensis Schlinger, 1960 Ogcodes porteri Schlinger, 1953 Ogcodes pusillus Paramonov, 1957 Ogcodes pygmaeus White, 1915 Ogcodes reginae Trojan, 1956 Ogcodes respersus Seguy, 1935 Ogcodes rufoabdominalis Cole, 1919 Ogcodes rufomarginatus Brunetti, 1926 Ogcodes sabroskyi Schlinger, 1960 Ogcodes schembrii Chvála, 1980 Ogcodes sexmaculatus Brunetti, 1926 Ogcodes shewelli Sabrosky, 1948 Ogcodes shirakii Schlinger, 1960 Ogcodes similis Schlinger, 1960 Ogcodes taiwanensis Schlinger, 1971 Ogcodes tasmannicus Westwood, 1876 Ogcodes tenuipes Paramonov, 1957 Ogcodes triangularis Sabrosky, 1945 Ogcodes trifasciatus De Meijere, 1915 Ogcodes trilineatus Brunetti, 1926 Ogcodes variegatus Brunetti, 1926 Ogcodes varius Latreille in Olivier, 1812 Ogcodes victoriensis Brunetti, 1926 Ogcodes vittisternum Sabrosky, 1948 Ogcodes waterhousei Paramonov, 1957 Ogcodes wilsoni Paramonov, 1957 Ogcodes zonatus Erichson, 1840
Subgenus Protogcodes Schlinger, 1960 Ogcodes hirtifrons Paramonov, 1957 Ogcodes paramonovi Schlinger, 1960 Subgenus Neogcodes Schlinger, 1960 Ogcodes albiventris Johnson, 1904
The following species are synonyms: Ogcodes darwinii Westwood, 1876: synonym of Ogcodes basalis (Walker, 1852) Ogcodes fumatus Froggatt, 1907 (preoccupied by O. fumatus Erichson, 1846): renamed to Ogcodes froggatti Schlinger in Schlinger & Jeffries, 1989 Ogcodes limbatus Bigot, 1888 (preoccupied by Henops limbatus Meigen, 1822, now Ogcodes pallipes Latreille in Olivier, 1812): renamed to Ogcodes bigoti Nartshuk, 1982
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