''Quadrastichus erythrinae'' Kim, 2004, (''quadra''=four, ''stichus''=line, ''erythrinae''=of erythrina) is a small

parasitoid In evolutionary ecology, a parasitoid is an organism that lives in close association with its host (biology), host at the host's expense, eventually resulting in the death of the host. Parasitoidism is one of six major evolutionarily stable str ...

wasp belonging to the family

Eulophidae The Eulophidae is a large family of hymenopteran insects, with over 4,300 described species in some 300 genera. The family includes the genus '' Elasmus'', which used to be treated as a separate family, "Elasmidae", and is now treated as a subfa ...

, but also a secondary phytophage by way of inducing galls on the leaves, stems, petioles and young shoots of various ''

Erythrina ''Erythrina'' is a genus of plants in the pea family, Fabaceae. It contains about 130 species, which are distributed in tropical and subtropical regions worldwide. They are trees, with the larger species growing up to in height. These species ...

'' species. ''Q. erythrinae'' was identified in 2004 in ''Erythrina'' galls collected in

Singapore Singapore, officially the Republic of Singapore, is an island country and city-state in Southeast Asia. The country's territory comprises one main island, 63 satellite islands and islets, and one outlying islet. It is about one degree ...

Mauritius Mauritius, officially the Republic of Mauritius, is an island country in the Indian Ocean, about off the southeastern coast of East Africa, east of Madagascar. It includes the main island (also called Mauritius), as well as Rodrigues, Ag ...

and

Réunion Réunion (; ; ; known as before 1848) is an island in the Indian Ocean that is an overseas departments and regions of France, overseas department and region of France. Part of the Mascarene Islands, it is located approximately east of the isl ...

. ''Eurytoma'' is a genus of wasps belonging to the family

Eurytomidae The Eurytomidae are a family within the superfamily Chalcidoidea. Unlike most chalcidoids, the larvae of many are phytophagous (feeding in stems, seeds, or galls), while others are more typical parasitoids, though even then the hosts are usuall ...

of which some are parasitoids of ''Quadrastichus'' species; a parasitoid from the Eulophidae is ''Aprostocetus exertus''.

Description

The female Quadrastichus erythrinae is described by as having dark brown coloring with yellow markings with the exception of the genae, which are brown on the back, the head is yellow. With the exception of the scape, which is pale in the back, the antennae are pale brown. The

pronotum The prothorax is the foremost of the three segments in the thorax of an insect, and bears the first pair of legs. Its principal sclerites (exoskeletal plates) are the pronotum (dorsal), the prosternum (ventral), and the propleuron (lateral) on e ...

has a deep brown color. An inverted triangle or "V" shaped region extending from the anterior border to the midlobe of the mesoscutum is dark brown, with the remaining portion being yellow. That's a yellow

scapula The scapula (: scapulae or scapulas), also known as the shoulder blade, is the bone that connects the humerus (upper arm bone) with the clavicle (collar bone). Like their connected bones, the scapulae are paired, with each scapula on either side ...

. The dorsellum, axillae, and scutellum are light brown to brown in color. There is a dark brown propodeum. Brown metasoma is present. The coxae at the front and rear are brown. The mid-coxa is nearly white. Most of the femora are light brown to brown in color. For the males, both the antenna and head are pallid. It is dark brown in the pronotum. Pale brown is the color of the dorsellum and scutellum. Axillae are pallid. Dark brown is the propodeum's color. The front part of the metasoma is pale, while the remaining portion is dark brown. Every leg has a pale color.

Mechanism

The female induces

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. Plant galls are abnormal outgrowths of plant tissues, similar to benign tumors or wart ...

in the leaves, shoots, petioles and

inflorescences In botany, an inflorescence is a group or cluster of flowers arranged on a plant's stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a main axis ( pe ...

of the plant. During the development of the gall, the affected organ is deformed, and the petioles and shoots become swollen.

Distribution

First collected in

Florida Florida ( ; ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders the Gulf of Mexico to the west, Alabama to the northwest, Georgia (U.S. state), Georgia to the north, the Atlantic ...

on coral trees ''Erythrina variegata'', now in

Miami Miami is a East Coast of the United States, coastal city in the U.S. state of Florida and the county seat of Miami-Dade County, Florida, Miami-Dade County in South Florida. It is the core of the Miami metropolitan area, which, with a populat ...

and

Hawaii Hawaii ( ; ) is an island U.S. state, state of the United States, in the Pacific Ocean about southwest of the U.S. mainland. One of the two Non-contiguous United States, non-contiguous U.S. states (along with Alaska), it is the only sta ...

; also known from Singapore, Mauritius and Reunion, Taiwan, Hong Kong, China, India, Thailand, Philippines, American Samoa, Guam and in the

Amami Islands The The name ''Amami-guntō'' was standardized on February 15, 2010. Prior to that, another name, ''Amami shotō'' (奄美諸島), was also used. is a Japanese archipelago in the Satsunan Islands, which is part of the Ryukyu Islands, and is sout ...

and

Okinawa most commonly refers to: * Okinawa Prefecture, Japan's southernmost prefecture * Okinawa Island, the largest island of Okinawa Prefecture * Okinawa Islands, an island group including Okinawa itself * Okinawa (city), the second largest city in th ...

in Japan. In Hawaii, it was first observed on the island of

Oahu Oahu (, , sometimes written Oahu) is the third-largest and most populated island of the Hawaiian Islands and of the U.S. state of Hawaii. The state capital, Honolulu, is on Oahu's southeast coast. The island of Oahu and the uninhabited Northwe ...

and later spread amongst other neighboring islands with major infestations on endemic '' Erythrina sandwicensis'' and introduced '' E. variegata''. It was then treated with parasitoid ''Eurytoma erythrinae'', which proved to be very effective in reducing the population of Erythrina gall wasps.

References

External links

''Quadrastichus erythrinae ''image
{{Taxonbar, from=Q5975927 Eulophidae