Tuesday's question was correctly answered by two overachievers, Nick Hobgood (who answered in about 16 seconds after the photo was posted) and Dave McKee (all the way from Jerusalem). The photo is of eggs inside the fused pelvic fins of a Robust Ghost Pipefish, Solenostomus cyanopterus.Ghost pipefishes comprise a small family (Solenostomidae) of skin-brooding fishes related to true pipefishes and seahorses (Syngnathidae). Solenostomus embryos develop within the fused pelvic fins of the female, unlike syngnathids in which males brood the eggs. Embryos, enclosed in egg envelopes, are attached to epidermal stalks, termed cotylephores, that occur only in brooding females.
For more details about pipefish reproduction, check out "Adaptations for reproduction and development in the skin-brooding ghost pipefishes, Solenostomus"
Coincidentally, I had posted another photo of a Robust Ghost Pipefish just a few days earlier.
