''Bassettia pallida'' is a species of

gall wasp Gall wasps, also incorrectly called gallflies, are hymenopterans of the family Cynipidae in the wasp superfamily Cynipoidea. Their common name comes from the galls they induce on plants for larval development. About 1,300 species of this generall ...

found in the

Southern United States The Southern United States (sometimes Dixie, also referred to as the Southern States, the American South, the Southland, or simply the South) is a geographic and cultural region of the United States of America. It is between the Atlantic Ocean ...

. This species was described by American entomologist William Harris Ashmead in 1896. ''B. pallida'' reproduces asexually in

galls Galls (from the Latin , 'oak-apple') or ''cecidia'' (from the Greek , anything gushing out) are a kind of swelling growth on the external tissues of plants, fungi, or animals. Plant galls are abnormal outgrowths of plant tissues, similar to be ...

induces Electromagnetic or magnetic induction is the production of an electromotive force (emf) across an electrical conductor in a changing magnetic field. Michael Faraday is generally credited with the discovery of induction in 1831, and James Cler ...

on oak trees. The parasite '' Euderus set'', a eulophid wasp, has ''B. pallida'' as a

host A host is a person responsible for guests at an event or for providing hospitality during it. Host may also refer to: Places * Host, Pennsylvania, a village in Berks County People *Jim Host (born 1937), American businessman * Michel Host ...

and manipulates its behavior.

Taxonomy

William Harris Ashmead described this species in 1896 based on a female specimen in the

National Museum of Natural History The National Museum of Natural History is a natural history museum administered by the Smithsonian Institution, located on the National Mall in Washington, D.C., United States. It has free admission and is open 364 days a year. In 2021, with 7 ...

. The

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...

was collected in 1884 in Georgia.

Distribution

This species has been found in the American states of Georgia, Florida, Missouri, Louisiana, and Texas. Its type location is

Savannah, Georgia Savannah ( ) is the oldest city in the U.S. state of Georgia (U.S. state), Georgia and is the county seat of Chatham County, Georgia, Chatham County. Established in 1733 on the Savannah River, the city of Savannah became the Kingdom of Great Br ...

Description

Adult female

The female is long. The

antenna Antenna ( antennas or antennae) may refer to: Science and engineering * Antenna (radio), also known as an aerial, a transducer designed to transmit or receive electromagnetic (e.g., TV or radio) waves * Antennae Galaxies, the name of two collid ...

e have thirteen joints. The head, antennae,

thorax The thorax or chest is a part of the anatomy of humans, mammals, and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main divisions of the cre ...

and legs are a brownish yellow color, while the posterior

tibiae The tibia (; ), also known as the shinbone or shankbone, is the larger, stronger, and anterior (frontal) of the two bones in the leg below the knee in vertebrates (the other being the fibula, behind and to the outside of the tibia); it connects ...

and eyes are dark brown and the abdomen is a polished black. A grooved line goes around the base of the scutellum.

Biology

Reproduction

The females can reproduce asexually in

gall Galls (from the Latin , 'oak-apple') or ''cecidia'' (from the Greek , anything gushing out) are a kind of swelling growth on the external tissues of plants, fungi, or animals. Plant galls are abnormal outgrowths of plant tissues, similar to be ...

s of the oaks '' Quercus geminata'', '' Quercus virginiana'', and '' Quercus minima''. These oak species are all in the ''

Virentes ''Quercus'' series ''Virentes'' ─ also called subsection ''Virentes'' ─ is a monophyletic group of seven North American evergreen or brevideciduous live oak species within the genus ''Quercus'' subgenus ''Quercus'' section ''Quercus''. * '' ...

'' subsection of ''

Quercus An oak is a tree or shrub in the genus ''Quercus'' (; Latin "oak tree") of the beech family, Fagaceae. There are approximately 500 extant species of oaks. The common name "oak" also appears in the names of species in related genera, notably '' ...

''. Galls are formed on the oaks' stem underneath the bark. Mature ''B. pallida'' come out of the galls in March or April, coinciding with the production of new leaves on the oak. Sexual reproduction is thought to happen afterwards in galls formed on the midvein of new leaves.

Parasites

The

chalcid wasp Chalcid wasps (, , for their metallic colour) are insects within the superfamily Chalcidoidea, part of the order Hymenoptera. The superfamily contains some 22,500 known species, and an estimated total diversity of more than 500,000 species, me ...

'' Euderus set'' parasitizes ''B. pallida''. This is a rare example of hypermanipulation, i.e., where one parasite which manipulates its host's phenotype has its own phenotype manipulated by a different parasite. In this case, ''B. pallida'' causes the oak to form a

, and ''E. set'' alters the behavior of ''B. pallida'' to create a hole in the gall and plug the hole with their head and die; ''E. set'' later emerges through a hole in its host's head. Only the asexual reproductive stage is targeted by ''E. set''.

References

{{Taxonbar, from=Q42301895 Cynipidae Oak galls Insects described in 1896 Hymenoptera of North America Insects of the United States Endemic fauna of the United States Taxa named by William Harris Ashmead