Swordtail or Platy?

Maude has a new boyfriend. His name, of course, is Stanley. I’m happy to report the mismatched pair hit it off right away.

Brick Red Swordtail and Green Swordtail

It’s a May/September, mixed marriage. Maude, the cougar, comes from the ‘Brick Red’ clan. Stanley is a young green swordtail–like those found in the wild. Maude clearly enjoys a walk on the wild side.

Like guppies, swordtails are live-bearers. Adult males are smaller than females, but longer because of the tail. Females produce 50 to 100 fry every 4-6 weeks. Newborns are visibly larger than guppy fry, but still little more than eyes with tails.

To be honest, I’m not interested in raising swordtails. Longtime readers may recall that Maude was supposed to be a platy–a similar species that’s hard to tell from swordtails when young. Maude may be a bit long in the tooth for childbearing. Stanley was intended more for company than procreation.

Though still peaceful as far as fish go, swordtails are the largest of the livebearers and the most aggressive. Platies are similarly colored/marked, but smaller and downright timid. Next trip to the pet store, I picked up a pair.

Scarlett is a sunset wag (black fins with an orange body that’s darker at the tail and lighter at the nose). Ashley is a velvet red wag (black fins and a deep orange body). Once they settled in, I realized Ashley was also a female.


Pair of Guppies

For anyone with good vision, sexing livebearers is easy. Females are larger and have a triangular ventral fin. Males are smaller, often prettier, and equipped with a hollow ventral fin that somewhat resembles a baby fish. I had to blowup a pic on my phone to see for sure.

Went to a different pet store for a male platy. Wanted some kind of wag (black fins), but said I’d take any male they could net. Ended up with a sunset platy I decided to call Rhett.

Stanley went after Rhett right away. Took a picture and, lo and behold, Rhett is a juvenile male swordtail.

Juvenile Sunset Swordtail (male)


I give up. Scarlet and Ashley intermingled with male platies at the store and are probably knocked up. Rhett stays in hiding to avoid a decidedly belligerent Stanley who has redoubled his efforts to make Maude a momma.

Will young Rhett survive endless assaults by randy Stanley? Are Maude’s eggs too old to fry? (Fry = baby fish–get it?) Will Scarlett and Ashley produce boyfriends for each other? As always, I’ll keep you posted.