From: Does the introduced polychaete Alitta succinea establish in the Caspian Sea?
Characteristics | Alitta succinea | Hediste diversicolor |
---|---|---|
Maximal length (mm) | 36 | 91 |
Mean length ± SD (mm) | 12.2 ± 20.3 | 49.4 ± 34.4 |
Maximal width at chaetiger 10 (mm) | 3.8 | 6.1 |
Mean width ± SD at chaetiger 10 (mm) | 1.7 ± 2.5 | 4.9 ± 3.3 |
Maximal no. chaetigers | 76 | 82 |
Extension of tentacular cirri | To chaetigers 3–8 (rarely 15) | To chaetigers 2–4 |
No. paragnaths on pharynx region 5 | 0–6 (usually 2) | Absent |
No. paragnaths on pharynx region 6 | A big one surrounded by 6–7 smaller ones | 3–9 |
Dorsal cirrus | Longer than ligules, inserted distally | Much shorter than ligules |
Dorsal notopodial ligules of posterior parapodia | Markedly enlarged and elongated | Not markedly enlarged |
Fused falcigers | Absent | Present |
Esophagus | Usually everted to ring 1 | Not inverted at all |
Color | Whitish to yellowish and brownish | Whitish to yellowish and greenish |
Substrate/sediment type | All sediment types, epi- and infaunal | Soft sediments, infaunal |
Epitokous stage | Present | Absent |