Table 1.
Morphological comparisons between the ten Diphyidae species from ethanol-fixed samples. O: presence; X: absence.
| Family | Diphyidae | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Genus | Chelophyes | Dimophyes | Diphyes | Eudoxoides | Lensia | Muggiaea | ||||
| Species | appendiculata | contorta | arctica | bojani | chamissonis | dispar | mitra | spiralis | cossack | atlantica |
| Author | Eschscholtz, 1829 | Lens & van Riemsdijk, 1908 | Chun, 1897 | Eschscholtz, 1825 | Huxley, 859 | Chamisso & Eysenhardt, 1821 | Huxley, 1859 | Bigelow, 1911 | Totton, 1941 | Cunningham, 1892 |
| Number of Nectophores | 2 | 2 | 2 | 2 | 1 | 2 | 2 | 1 | 1 | 1 |
| Number of Nectophore Types | 2 | 2 | 2 | 2 | 1 | 2 | 2 | 1 | 1 | 1 |
| Comparison of Nectophore Size | Anterior > Posterior | Anterior > Posterior | Anterior > Posterior | Anterior ≥ Posterior | X | Anterior > Posterior | Anterior > Posterior | X | X | X |
| Shape of Anterior Nectophore | Bullet-shape | Bullet-shape | Bullet-shape | Bullet-shape | Bullet-shape | Triangular Bullet-shape | Bullet-shape | Twisted Bullet-shape | Bullet-shape | Bullet-shape |
| Shape of Apex | Pointed | Pointed | Blunt | Pointed | Pointed | Pointed | Pointed | Pointed | Blunt | Pointed |
| Longitudinal Ridges | 5 | 4 | X | 5 | 5 | 5 | 5 | 5 | 5 | 5 |
| Hydroecium Depth | Medium | Medium | Medium | Deep | Deep | Deep | Medium | Medium | Shallow | Deep |
| Hydroecium Shape | Claw-shaped | Claw-shaped | Rounded | Rounded | Rounded | Rounded | Rounded | Rounded | Flatted | Rounded |
| Ostial Teeth | X | X | X | O | O | O | X | X | X | X |
| Mouthplate | Divided | Divided | Undivided | Undivided | Undivided | Undivided | Divided | Divided | Divided | Divided |
| Shape of Somatocyst | Fusiform | Oblique Club-shaped | Fusiform | Fusiform | Fusiform | Fusiform | Fusiform | Fusiform | Ovoid | Filiform |
| Length of Somatocyst Stalk | Short | Long | Short | Short | Short | Short | Short | Short | Short | Short |
| Somatocyst/Anterior Nectosac | 1/2–3/4 | 1/2 | 1/2–3/4 | 1/2 | 1/2–1/3 | 1/3–1/4 | 1/2–1/3 | 1/2–1/3 | 1/3 | 4/5 |