Conjoinings (Interspecies and Otherwise)

Spiders have spiderlings, cats have their kittens.
Elbow-length gloves perhaps produce mittens.
Whenever a boy cockroach happens to mount her,
a girl cockroach procreates right on my counter!

Such coteries tend to insist on inbreeding,
but the world’s solidarity comes from cross-seeding.
Thus, mermaids lure sailors onto the rocks
for intercourse better confined to their docks.

When horses and zebras conjoin, then of course,
the end is a hebra, or perhaps  a zorse?
A tiger from Asia and lion from Niger
might call their offshoot a tion or liger.

The tone of this poem? I admit it is crass.
It ends with a haddock  shtupping a bass.
resulting in baddocks or perhaps a hass.
Another stanza? Bet you’re glad that I pass!!

Prompt words are spiderling, tone, solidarity, coterie, counter and dock.