4/21/2022: Black German progress

Roach keepers in the United States have been ashamed to admit for some time that the “easiest” roach to keep, the one that can be found at infestation levels in apartments, dorm rooms, and buffets across the planet, can be difficult to propagate intentionally.

This is no particularly fault of Blattella germanica’s doing, rather that captive set-ups to tend to have lower ventilation and more humidity than the species prefers, and these conditions over time can cause irreparable culture crashes.

Such was the case with the beloved “Black” strain, which was lost almost completely around 2018. The original group came from a university, though over many months I refined the coloration to consistently produce black, unmarked individuals, and this was the line distributed as “Black”. Upon losing my original group, I was sent more from various sources multiple times, and upon hearing the basal source may be in danger, I realized all I had left were two sub-par quality adult males.

Thinking quickly, I crossed these with an “Alexandria” female, and from there as my husbandry and schedule improved I was able to get a good colony of these “mutts” going.

After doing multiple crosses I noticed that a lighter, browner phenotype was possible, and despite setting up two lines to prove out both the black and browns, the black line failed for various reasons and I was left with a fairly consistent brown phenotype. This is in the final stages of refinement, as 1% of the colony shows adult markings, but I believe by July I’ll have just what I’d hoped for and will release that with a new strain name.

As for the original “Black”, the basal colony didn’t go extinct and I have been able to select and play with more genes from that. Many individuals bearing the desired phenotype have popped up, but proving it out entirely has been riddled with setbacks. Still, I remain optimistic and think by December and truly black “Black 2.0” will be ready to go.

Pest species may not be thrilling to everyone, but due to their relatively large numbers and establishment in many different geographical places and environments they display a lot of phenotypic diversity. Similar to the current Periplaneta americana strains, it would be captivating to isolate some equally wacky multi-gene Blattella projects.

-Kyle