New records of aphid parasitoids (Hymenoptera) from Colombia

Aphid parasitoids have been recorded in many countries around the globe, however records in Colombia are few. Here, five primary parasitoids species, Aphidius platensis Brèthes, 1913, Aphidius funebris Mackauer, 1961, Aphidius matricariae Haliday, 1834, Aphelinus varipes (Förster, 1841), Aphelinus paramali Zehavi & Rosen, 1989, and two hyperparasitoids species, Syrphophagus aphidivorus (Mayr, 1876) and Pachyneuron aphidis (Bouché, 1834) are newly recorded in Colombia. Two other primary parasitoids, Lysiphlebus testaceipes (Cresson, 1880) and Aphidius colemani Viereck, 1912 are newly recorded from the department of Valle del Cauca. 

Evolution of glandular structures on the scape of males in the genus Aphelinus Dalman (Hymenoptera, Aphelinidae)

The pores and associated glands on male antennae in species of Hymenoptera are involved in mate recognition and are diverse and widespread among taxa. However, nothing has been published about these structures in species of Aphelinus (Chalcidoidea: Aphelinidae), a genus of parasitoid wasps with a long history in biological control. Images from scanning electron microscopy (SEM) and transmission electron microscopy (TEM) of Aphelinus varipes revealed pores on the ventral side of the male scape that were connected to glands. A survey of the scapes of male antennae in 16 species in six species complexes of Aphelinus, as well as two outgroup species, Aphytis melinus and Centrodora sp., showed that pores were present in all except Centrodora sp. The pores varied in several characters: the shape of the structures that carried them, pore size, elevation of the cuticle surrounding the structures, the extent of a carina delimiting the area around the structures, and the number and position of pores. The shape of the pore-bearing structures, the elevation of cuticle around these structures, and the extent of the carina around them map well onto a molecular phylogeny of these Aphelinus species. Combinations of pore characters are diagnostic of species complexes, and in some cases, species of Aphelinus.

EFFECTS OF PHOTOPERIOD AND TEMPERATURE ON DIAPAUSE OF TWO APHEL1NUS SPP. (HYMENOPTERA: APHELINIDAE) PARASITIZING THE RUSSIAN WHEAT APHID

The effects of photoperiod and temperature on the diapause of Aphelinus varipes (Focrster) from Kazakhstan and Apheiinus near varipes from Alberta, which both attack Russian wheat aphid, were studied in the laboratory. At 20 °C, 50% of A. varipes entered diapause when the photoperiod was between 12.5L:11.5D and 13L:11D whereas 50% of A. nr. varipes entered diapause when the photoperiod was around 14L:10D. Diapause induction was close to 100% at 11.5L:12.5D for both species. Maximum sensitivity to photoperiod occurred 2 days alter parasitization for A. varipes and 3 days after parasitization for A. nr. varipes. At 30 °C, the proportion of wasps entering diapause was reduced to 40 and 72% for A. varipes and A. nr. varipes, respectively. Exposing diapausing mummies to temperatures from 10 to −10 °C for 4–20 weeks shortened the postdiapause developmental time. Survival was lowered by exposing mummies to −10 °C for over 8 weeks. Postdiapause developmental rate was directly temperature dependent. The lower threshold and thermal constant for postdiapause development were estimated to be 10.3 °C and 189 degree-days (DD) for A. varipes and 7.41 °C and 204 DD for A. nr. varipes.