Strange, weird or odd or whatever beach finds thread….

On my last visit to Nisqually NWR, a dead spotted ratfish, Hydrolagus colliei, was washed up on the mudflat.
CSpottedRatfish5840.jpg
I have no idea of the cause of death. While other ratfish species are more typically found in deep water, I have encountered spotted ratfish several times while diving in the San Juan Islands (and they are pretty common in research otter trawls). They are pretty wary of divers and will swim away by flapping their pectoral fins. Unlike the replaceable teeth of sharks, ratfish have plate-shaped incisors on the upper and lower jaw (hence the genus name Hydrolagus = "water" "rabbit").
The ratfish have been placed in their own class, the Holocephali, within the class Chondrichthyes (cartilaginous fishes). Unlike the other Chondrichthyans, the upper jaws of ratfishes are fused to their skulls. Also, ratfishes have a single gill opening per side, while other Chondrichthyans have 5-7 gill slits per side.
Steve
 
On my last visit to Nisqually NWR, a dead spotted ratfish, Hydrolagus colliei, was washed up on the mudflat.
Many years ago I found a Ratfish with it's dorsal barb stuck in the web between my thumb & index finger. I had no clue what it was. Asked an old-timer nearby what happens if one spines you. "Yer gonna get sick." The puncture bled profusely and I felt zero ill effects.
 
Many years ago I found a Ratfish with it's dorsal barb stuck in the web between my thumb & index finger. I had no clue what it was. Asked an old-timer nearby what happens if one spines you. "Yer gonna get sick." The puncture bled profusely and I felt zero ill effects.
You were fortunate. There are poison glands at the base of the serrated dorsal spine. The venom has been reported to be painful in humans, but not deadly. But there were several deceased harbor seals that had eaten spotted ratfish; the hypothesis is that the sharp spine penetrated their internal organs and allowed the venom into the seals' blood. There doesn't appear to have been much research into the actual identity of the toxin.
Steve
 
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