Dicoelothorax platycerus

Dicoelothorax platycerus
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Eucharitidae
Subfamily:	Eucharitinae
Genus:	Dicoelothorax
Species:	D. platycerus
Binomial name
Dicoelothorax platycerus Ashmead, 1904

Distribution

Argentina, Bolivia, Brazil

Biology

Host ant: Ectatomma brunneum

Collections of adults of Dicoelothorax platycerus, Pseudabutilon virgatum, and ant nests were made in 2009 (March 12) and 2010 (March 27 and April 3). Females placed in plastic tubes were observed ovipositing on the undersides of the leaves of Pseudabutilon virgatum (Figs 17, 18). A single gravid female oviposited about 40 eggs per 1 mm2 between the spicules forming the pubescence on the underside of leaves (Figs 17, 18). Numerous mites were observed on the leaves, and oviposition under the dense network of spicules appears to be a protection against egg predators. Eggs hatched within 10 days; however, many of the remaining eggs contained mature planidia that did not hatch. First instars (planidia) are very mobile and have a propensity to jump. Larvae presumably attach phoretically to foraging ants under the host plant and get carried back to the ant nest where they attack the ant larvae (Clausen 1941). Of two pupae of Dicoelothorax platycerus obtained in H1, one male emerged 12 days after the nest was excavated; whereas the other pupa (female) did not emerge (Figs 26–31). The percentage of parasitism ranged from 6.2% in H2 to 21% in H1. In nest H1, 17 cocoons were recovered, with two pupae of Dicoelothorax platycerus (1 female and 1 male) and 2 ant prepupae parasitized by second instars of Dicoelothorax platycerus (Fig. 24). In nest H2, 97 larvae were recovered with 6 parasitized by planidia (Fig. 25).

References

• Ashmead, W.H. Classification of the chalcid flies of the superfamily Chalcidoidea, with descriptions of new species in the Carnegie Museum, collected in South America by Herbert H. Smith. JOURBOOK: Memoirs of the Carnegie Museum VOLUME: 1(4) PAGES: i-xi,225-551,39pls. (1904).

• Heraty, J.M. 2002. A revision of the genera of Eucharitidae (Hymenoptera: Chalcidoidea) of the World. Memoirs of the American Entomological Society 68: 1-359.

• Heraty JM, Mbanyana N, Noort SV (2020) A new species of Eucharissa Westwood (Eucharitidae) from South Africa, with an evaluation of the importance of pupae for assessing relationships in these ant parasitoids. Journal of Hymenoptera Research 79: 43–55. https://doi.org/10.3897/jhr.79.56042

• Risbec, J. (1952) Contribution á l'étude des chalcidoides de Madagascar., JOURBOOK: Mémoires de l'Institut Scientifique de Madagascar (E) VOLUME: 2 PAGES: 1-449

• Torréns J, Heraty J (2012) Description of the species of Dicoelothorax Ashmead (Chalcidoidea, Eucharitidae) and biology of D. platycerus Ashmead. ZooKeys 165: 33-46.

• Westwood, J.O. 1868. Descriptions of new genera and species of Chalcididae. Proceedings of the Entomological Society of London 1868:xxxvii