midlinedorsal

Midlinedorsal is an anatomical descriptor used in biology to indicate a feature located along the dorsal midline—the center line of the back or upper surface of an organism. The term combines midline (the line dividing left and right) and dorsal (the back side). In descriptive morphology, midlinedorsal describes lines, stripes, crests, sutures, or color patterns that run along the center of the dorsum from head to tail. It is commonly applied in ichthyology (fish), herpetology (reptiles and amphibians), and entomology, and can also appear in paleontological descriptions of fossil vertebrates.

A midlinedorsal feature is defined by its position rather than its composition. Examples include a midline dorsal stripe or a midline row of scales or plates that extend along the back, or a mid-dorsal fin crest aligned with the body midline. The term is often used in diagnostic keys and field descriptions to distinguish species or individuals whose dorsal patterns follow the midline versus those with off-midline markings.

In practice, midlinedorsal is relative to the observer's orientation, and when used in clinical or anatomical contexts it forms part of a broader vocabulary for describing location along the body’s axes (dorsal, ventral, lateral, medial, etc.). The term is descriptive and may vary in precision across taxa.