January 27, 2021

Separating the two Vespula species in NZ


According to "Social Wasps, their biology and control" (available on academia.edu), males can only be separated with reference to genitalia:

"Since the genitalia of the males are very characteristic and essential for correct identification, it is recommended that these parts should be extracted with fine needle as soon as the specimen has been killed."
Page 330/331, start of chapter "The British Species"

For the key to species, the only character given for males to separate vulgaris and germanica relates to genitalia.
For vulgaris: "Penis of males with a small barb on each side below the apical expansion which is not emarginate at the tip."
For germanica: "Penis of males with a small semicircular process on each side below the apical expansion, which is emarginate at the tip."
Couplet 6, Pages 337/338.

Similarly, from another New Zealand study: "Fifteen percent of common males had the typical German frontal patch colour marking, with no yellow extensions of the lower margin (Fig. 13A). Clypeal marks of both species were very variable (and quite different from those of workers and queens) (Fig. 14). They did not separate the species."
Clapperton BK, Lo PL, Moller H, Sandlant GR (1989) Variation in colour markings of German wasps Vespula germanica (F.) and common wasps Vespula vulgaris (L.) (Hymenoptera: Vespidae) in New Zealand. New Zealand Journal of Zoology 16:303–313. https://doi.org/10.1080/03014223.1989.10422895

Workers & Queens

Distinguishing workers and queens is possible by using the genal band, clypeal pattern, or markings on the pronotum. Markings on the abdomen are too variable and do not allow accurate identification, as detailed in Clapperton et al and also:
Donovan BJ (1984) Occurrence of the common wasp, Vespula vulgaris (L.) (Hymenoptera: Vespidae) in New Zealand. New Zealand Journal of Zoology 11:417–427. https://doi.org/10.1080/03014223.1984.10428256

Posted on January 27, 2021 08:19 by tom_saunders tom_saunders | 0 comments | Leave a comment

January 02, 2021

Steve Kerr on crane fly keys in NZ

Alexander 1920 - 1924 (about ten papers total during this period) and Edwards 1923 ... all available via BUGZ. I also have a small word doc sent to me by Peter Johns that zeroes in on Chlorotipula.

Posted on January 02, 2021 21:34 by tom_saunders tom_saunders | 0 comments | Leave a comment

December 16, 2020

Chris Cohen on the 3 genera of Asilidae in NZ

Well, you only have three commonly-encountered genera in NZ, all of which are probably not congeneric with their European counterparts.

"Neoitamus": antennae ending in narrow, tapering element (=Asilinae); ovipositor consisting of multiple sclerotized segments (giving the posterior abdomen a "jagged" appearance) and ovipositor rounded in cross-section; male genitalia relatively large and bulbous; habitus relatively large and robust (compared to the other two genera).
female: https://www.inaturalist.org/observations/64741020
male: https://www.inaturalist.org/observations/64002149

"Cerdistus": antennae ending in narrow, tapering element (=Asilinae); female ovipositor laterally-compressed and blade-like, consisting of only the terminal segment; male genitalia not bulbous; habitus relatively small and gracile.
female: https://www.inaturalist.org/observations/66589727
male: https://www.inaturalist.org/observations/38381577

"Saropogon": terminal segment of antennae broad, cylindrical throughout; female ovipositor blunt-ended and with acanthophorite spines; male genitalia fairly nondescript; habitus robust.
female: https://www.inaturalist.org/observations/59099637
male: https://www.inaturalist.org/observations/59858701

Posted on December 16, 2020 18:56 by tom_saunders tom_saunders