There are four types of fish scales!
Cycloid scales are thin, overlap, and flexible. They're found on primitive teleosts (like minnows and carp).
Ctenoid scales have small, backwards pointed scales (known as cterns) make the fish more hydrodynamic and faster. They're found on Advanced Ctenoids (like perch and sunfish).
Ganoid scales are thick, diamond-shaped, and mostly non-overlapping. They're found on Chondrostei (like sturgeons and paddlefish).
Placoid scales are spikey and tooth-like with nerves. These are found on Chondrichthyes (like sharks and rays).
Ichthyology Notes 3/?
Flowers 🌸🌸
For your information, there's a lot more to ogres than people think.
SHREK (2001) dir. Andrew Adamson, Vicky Jenson
Montjuic cemetery in Barcelona
Compared to other colors found in nature, true blues are pretty rare—but the indigo milk cap (Lactarius indigo) has just that! This vibrant mushroom gets its color from a pigment that is a derivative of guaiazulene, a dark blue crystalline hydrocarbon. You would think that its blueness is a marker for toxicity, but the mushroom is actually edible—although its color fades to a grayish hue when it’s cooked.
Photo: Andrey Loria, CC BY-SA 4.0, iNaturalist
Falling down on a sunny day
Moon & clouds.