Telling gender on Therea spieces

[lovebugfarm]

I just had 4 domino roaches mature and i took each out and looked at them but they all look like males. Is it common for one gender to mature faster then anouther? Any link or pics? I tryed to search gender on the forum and the word se x is blocked. Which i feel is an oversite since it means the same as gender. A search for female turned up top view pics. Also what is the term for iding gender based on underside last segement shape? Im a lil frazzled since these all look male. Pretty sure i have 3 more nymphs about to be adults i will take them out tomorrow to see if they are girls.

 

[Tenevanica]

Therea sp. can have a male:female ratio of 10:1 sometimes. You can sex therea by looking at their antennae. Males have longer hairy antennae, (supposedly for detecting pheromones put of by the female) while females have short straight antennae. I don't know how to ventrally sex Polyphagids.

 

[Hisserdude]

Sexing Corydiids/Polyphagids ventrally is quite easy, the adult female's last segment is very large and has a noticeable bulge, whist the male just has two small segments.

See here:

The female has one big last segment, and the male just has two small ones. Hope this helps!

 

[lovebugfarm]

Thanks guys i guess the 10.1 ratio thing is whats going on. I will just enjoy watching them run around while I wait a year till the newly hatched nymphs mature.