Eglonaspididae

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Eglonaspididae is a family of extinct armored jawless fishes from the Early Devonian period. Fossils have been found in marine rocks in Siberia near the Taimyr Peninsula. Members of this family were benthic bottom-dwellers that likely lived buried in sediment in hypersaline lagoons. Their head armor plates fused into a single muff-like unit, giving the front part of the body a bottle-like shape. In life, they probably had small or no eyes and a simple, slit-like mouth at the front of the head shield.

Taxonomy
Genera in the family Eglonaspididae include Eglonaspis, Gerronaspis, Lecanaspis, Empedaspis, and Pelurgaspis.

Genus descriptions
- Eglonaspis: A triangular cephalothoracic shield with large, crenulated fringes at the back edges and a tube-like head. It appears to have had no eyes, and may have filtered food from the water while buried.
- Gerronaspis: Originally described as Putoranaspis dentata, Gerronaspis has an oval shield with fringed edges near the ends. The head is short with small eye openings that are relatively large for this group.
- Lecanaspis: Very similar to Eglonaspis, with a triangular head shield and a tubular head, and likely no eyes.
- Empedaspis: Known from a large fragment of the front shield; the complete animal would have had a hot-water-bottle–shaped cephalothorax, possibly with wing-like extensions, and small eyes.
- Pelurgaspis: Known from an incomplete triangular shield; the full shield may have been corn-kernel or guitar-pick shaped, with eyes at the front of a small head.