היומן של zdanko

There are three species of Condylostylus that we don't have a lot of information on, and that are very similar. They are C. inornatus, C. quadricolor, and C. leonardi. All three differ from other marked wing species by having the fore tibiae yellow. Here I will be adding information and accumulating links to possible and confirmed observations.

C. inornatus

Unlike the other species, the mid tibia is dark.
Confirmed observations:
https://www.inaturalist.org/observations/93545891

C. quadricolor

Unlike C. leonardi, the hind tarsal segments steadily decrease in length, and the border of the green-black areas on each tergite is diffuse.
Confirmed observations:
https://www.inaturalist.org/observations/123902280
https://www.inaturalist.org/observations/123182305
https://www.inaturalist.org/observations/115937086
https://www.inaturalist.org/observations/109613622
https://www.inaturalist.org/observations/106406506
https://www.inaturalist.org/observations/93687482
https://www.inaturalist.org/observations/84493302
https://www.inaturalist.org/observations/74010927
https://www.inaturalist.org/observations/39780304

Likely, based on range:
https://www.inaturalist.org/observations/77148364
https://www.inaturalist.org/observations/20934981
https://www.inaturalist.org/observations/138153856
https://www.inaturalist.org/observations/129845812
https://www.inaturalist.org/observations/73957125
https://www.inaturalist.org/observations/123017348
https://www.inaturalist.org/observations/18872833

C. leonardi

Unlike C. quadricolor, the last three hind tarsal segments are all subequal in length, and the border of the green-black areas on each tergite is sharp.
Confirmed observations:
https://www.inaturalist.org/observations/133698570
https://www.inaturalist.org/observations/133860943
https://www.inaturalist.org/observations/120273319
https://www.inaturalist.org/observations/105136835
https://www.inaturalist.org/observations/36996072
https://www.inaturalist.org/observations/133712421

Likely, based on range:
https://www.inaturalist.org/observations/133635244
https://www.inaturalist.org/observations/92814269
https://www.inaturalist.org/observations/93199299

Females

of C. quadricolor and C. leonardi are distinct from females of the C. sipho group in that they have a dark posterior area on the hind femora.
Observations:
https://www.inaturalist.org/observations/120273316
https://www.inaturalist.org/observations/123320254
https://www.inaturalist.org/observations/60385421
https://www.inaturalist.org/observations/115995861
https://www.inaturalist.org/observations/106406502
https://www.inaturalist.org/observations/128160949
https://www.inaturalist.org/observations/76041141
https://www.inaturalist.org/observations/121393367
https://www.inaturalist.org/observations/64223604
https://www.inaturalist.org/observations/96330119
https://www.inaturalist.org/observations/115414488
https://www.inaturalist.org/observations/76968353
https://www.inaturalist.org/observations/91027484

This species is diagnosed by the two longitudinal yellow stripes on the scutum, disconnected sutural and humeral spots on the scutum, and a black abdomen with narrow, uniform yellow apical bands with large yellow spots on the side of the first segment.

https://www.inaturalist.org/observations/52069034
https://www.inaturalist.org/observations/21163268
https://www.inaturalist.org/observations/129997735
https://www.inaturalist.org/observations/126150006
https://www.inaturalist.org/observations/29201520
https://www.inaturalist.org/observations/123450844
https://www.inaturalist.org/observations/88863882
https://www.inaturalist.org/observations/52356940
https://www.inaturalist.org/observations/133986720

https://www.inaturalist.org/observations/88854765
https://www.inaturalist.org/observations/85573129
https://www.inaturalist.org/observations/25950669
https://www.inaturalist.org/observations/83324623
https://www.inaturalist.org/observations/80819163
https://www.inaturalist.org/observations/3160480
https://www.inaturalist.org/observations/278868
https://www.inaturalist.org/observations/47785154
https://www.inaturalist.org/observations/7855384
https://www.inaturalist.org/observations/32509527
https://www.inaturalist.org/observations/27196276
https://www.inaturalist.org/observations/3700373
https://www.inaturalist.org/observations/4878724

Decided to make this a post so I can get these out of my favorites list.

Coenomyia:
https://www.inaturalist.org/observations/81312061

Xylophagus:
https://www.inaturalist.org/observations/42116441
https://www.inaturalist.org/observations/83469137
https://www.inaturalist.org/observations/79593054
https://www.inaturalist.org/observations/74737245

Eastern Dialysis:
https://www.inaturalist.org/observations/27849101
https://www.inaturalist.org/observations/88186254
https://www.inaturalist.org/observations/87231357
https://www.inaturalist.org/observations/86993919
https://www.inaturalist.org/observations/85697262

Western Dialysis:
https://www.inaturalist.org/observations/49779033
https://www.inaturalist.org/observations/51276212
https://www.inaturalist.org/observations/25950669
https://www.inaturalist.org/observations/3219471

My experience with rearing Syrphids is limited to aphid-eating predators. For information about rearing larvae that don't feed on aphids, refer to Rotheray, 1993 (see footnote*).

With the assistance of @edanko, I have reared three Syrphine species: Allograpta obliqua, Eupeodes americanus, and Syrphus knabi. All three of the genera predate on aphids. Here's how I went about it:

First, put the larva in a small, preferably plastic, container. You can choose to put a layer of paper towel on the bottom right now if you wish. Put a layer of paper towel covering the opening of the container, and attach with a rubber band.

Next, you'll want to find a healthy colony of aphids to harvest from. If possible, it's preferable to take from the colony you found the larva on. Every morning and every evening, depending on how fast your larva eats, take a leaf of aphids and put it in the container with the larva. This worked for me, but I'm sure there are more efficient ways of doing that.

Once the larva pupates, if you didn't already, put paper towel on the bottom of the container so it doesn't roll around. Now, all you have to do is wait. Check on the pupa throughout the days to see if the fly has emerged. Once it has, your time to photograph it is limited.

My method to photograph is to put the container in a large ziploc bag, and push the lens through the opening of the bag, leaving as little space as possible for the fly to escape. Hopefully, at this point it's recently eclosed, so it won't fly that much.

Once you have the necessary photos, you can try, if you're confident enough, to get the fly on your finger or another rigid object, and carry it outside. There, you can get better photos with nice lighting, and once the fly is ready, it can leave your finger and fly away.

Thanks for reading! I hope this is helpful. If you have any ideas or suggestions, please leave them in a comment or message me so I can edit this post. This is somewhat of a wiki, as I want this to be a good resource for rearing predatory Syrphids. See comments below from other people with experience in this for some more tips.

*(See p. 26: https://diptera.info/downloads/df_1_9_Colour_Guide_to%20Hoverfly_Larvae.pdf)