Trissolcus basalis

{{Short description|Species of wasp}} {{Speciesbox | image = Trissolcus basalis lateral.jpg | image_caption = Lateral view of female ''T. basalis''. | genus = Trissolcus | species = basalis | authority = (Wollaston, 1858) | synonyms = *''Telenomus basalis'' Wollaston, 1858 *''Microphanurus basalis'' Wollaston, 1858 *''Asolcus (Microphanurus) basalis'' Wollaston, 1858 *''Asolcus basalis'' Wollaston, 1858 *''Telenomus maderensis'' Wollaston, 1858 *''Trissolcus maderensis'' Wollaston, 1858 *''Telenomus megalocephalus'' Schulz, 1894 *''Telenomus megacephalus'' Ashmead, 1894 *''Liophanurus megacephalus'' Ashmead, 1894 *''Microphanurus megacephalus'' Ashmead, 1894 *''Trissolcus megacephalus'' Ashmead, 1894 *''Telenomus piceipes'' Dodd, 1920 *''Trissolcus piceipes'' Dodd, 1920 *''Microphanurus africanus'' Fouts, 1934 *''Trissolcus africanus'' Fouts, 1934 *''Microphanurus sulmo'' Nixon, 1938 *''Asolcus sulmo'' Nixon, 1938 *''Trissolcus sulmo'' Nixon, 1938 *''Asolcus lodosi'' Szabó, 1981 *''Trissolcus lodosi'' Szabó 1981 }}

'''''Trissolcus basalis''''', or the '''green vegetable bug egg parasitoid''', is a parasitoid wasp in the family Platygastridae known primarily for parasitising the horticultural pest ''Nezara viridula'', the green vegetable bug.<ref>{{Cite journal|last1=Powell|first1=Janine E.|last2=Shepard|first2=Merle|date=1982|title=Biology of Australian and United States strains of Trissolcus basalis, a parasitoid of the green vegetable bug, Nezara viridula|journal=Australian Journal of Ecology|volume=7|issue=2 |pages=181–186|doi=10.1111/j.1442-9993.1982.tb01591.x|bibcode=1982AusEc...7..181P }}</ref>

== Description ==

Like other species of ''Trissolcus'', ''T. basalis'' is small (around 2mm long), mostly black in colour, and females have clubbed antennae.<ref name="cornell" /> ''Trissolcus basalis'' can be separated from other nearctic ''Trissolcus'' species by the presence of coriaceous microsculpture on the mesoscutellum, pustulate setal bases, shallowly impressed episternal foveae on the mesopleuron, and an incomplete netrion sulcus.<ref>{{Cite journal|last1=Buffington|first1=Matthew|last2=Johnson|first2=Norman F.|last3=Talamas|first3=Elijah J.|date=2015-03-27|title=Key to Nearctic species of ''Trissolcus'' Ashmead (Hymenoptera, Scelionidae), natural enemies of native and invasive stink bugs (Hemiptera, Pentatomidae)|url=https://jhr.pensoft.net/article/4987/|journal=Journal of Hymenoptera Research|language=en|volume=43|pages=45–110|doi=10.3897/JHR.43.8560|issn=1314-2607|doi-access=free}}</ref>

== Life cycle == ''Trissolcus basalis'' is a solitary endoparasitoid, completing development within the eggs of pentatomid bugs.<ref>{{Cite journal|last=Wilson|first=F.|date=1961|title=Adult reproductive behaviour in Asolcus basalis (Hymenoptera: Scelionidae)|url=http://www.publish.csiro.au/zo/ZO9610739|journal=Australian Journal of Zoology|language=en|volume=9|issue=5|pages=739–751|doi=10.1071/zo9610739|issn=1446-5698|url-access=subscription}}</ref> Females use their clubbed-shape antennae to palpate eggs laid by their primary host, ''Nezara viridula''. When ready to oviposit, the female faces away from the egg and backs into it, inserting her ovipositor through the wall of the egg. Once finished ovipositing, the female withdraws her ovipositor and wipes the tip across the egg surface to mark the egg also with pheromones.<ref>{{cite journal |last1=Rosi |first1=M. C. |last2=Isidoro |first2=N. |last3=Colazza |first3=S. |last4=Bin |first4=F. |title=Source of the host marking pheromone in the egg parasitoid Trissolcus basalis (Hymenoptera: Scelionidae) |journal=Journal of Insect Physiology |date=1 September 2001 |volume=47 |issue=9 |pages=989–995 |doi=10.1016/S0022-1910(01)00073-7 |pmid=11472761 |bibcode=2001JInsP..47..989R }}</ref> Female wasps defend the eggs they have already parasitized. After adults have completed development, males emerge from unfertilized eggs first followed by females a couple of days later. Males mate with females as they emerge from the egg.

== Ecology == In New Zealand, ''T. basalis'' has been recorded from non-target hosts including ''Cermatulus nasalis'' (Woodward, 1837), ''Cuspicona simplex'' Walker, 1867, Green potato bug, ''Dictyotus caenosus'' (Westwood, 1837), ''Glaucias amyoti'' (Dallas, 1851), ''Monteithiella humeralis'' (Walker, 1868), and ''Oechalia schellenbergii'' (Guerin, 1831).<ref name=":0" /> It has no known natural enemies in New Zealand, although ''Acroclisoides'', a genus containing a species known to hyperparasitise ''T. basalis'' in Australia, is known to be present in New Zealand.<ref>{{Cite web|url=https://inaturalist.nz/observations/12495341|title=Acroclisoides observed in Auckland|last=Saunders|first=Tom|date=March 2018|website=iNaturalistNZ}}</ref>

== Distribution ==

''Trissolcus basalis'' is considered to be an effective biocontrol agent in New Zealand, Australia, and the United States as well as in middleuropean countries, all places where it was deliberately introduced.<ref name=cornell>{{Cite web|url=https://biocontrol.entomology.cornell.edu/parasitoids/trissolcus.php|title=Trissolcus basalis|website=Cornell University College of Agriculture and Life Sciences|access-date=7 February 2019}}</ref> In 1949 ''T. basalis'' was released in New Zealand in an effort to control damage caused to crops including sweet corn and green beans by ''Nezara viridula''.<ref name=":0">{{Cite web|url=https://nzacfactsheets.landcareresearch.co.nz/factsheet/InterestingInsects/Green-vegetable-bug-egg-parasitoid---Trissolcus-basalis.html|title=Green vegetable bug egg parasitoid - Trissolcus basalis|last=Martin|first=Nicholas|website=Interesting Insects and other Invertebrates: New Zealand Arthropod Factsheet Series}}</ref> Over 48,000 parasitoids were reared from a shipment of between 200 and 300, and these were released at Awanui, Kaitaia, Paihia, Kawakawa, Whangarei, New Plymouth and Te Kaha (Bay of Plenty).<ref>{{Cite journal|last=Cumber|first=R. A.|date=1950|title=The introduction into New Zealand of ''Microphanurus basalis'' Woll. (Scelionidae: Hym.), egg parasite of the green vegetable bug, ''Nezara viridula'' L. (Pentatomidae)|url=http://www.bugz.org.nz/WebForms/ResultDetails.aspx?CurrentDoc=1E02675E-153E-4D8A-9AF7-0C681DB5C65E&back=true&NewDoc=true&searchType=1&SearchString=cumber|journal=The New Zealand Journal of Science and Technology, Section B|volume=32|issue=5 |pages=30–37}}</ref>

== References == {{Reflist}}

Category:Parasitoid wasps Category:Insects described in 1858 Category:Platygastridae