| Family: |
Themistidae (themistids) |
| Max. size: |
2.5 cm TRKL (male/unsexed) |
| Environment: |
benthic; marine |
| Distribution: |
Pacific Ocean: Japan, Sea of Okhotsk, the Sea of Japan, Gulf of California (Ref. 1815). |
| Diagnosis: |
Large animals, from brownish-yellow to dark brown in color. Body 0.1 - 0.6 cm long, spindle shaped spindle shaped or cylindrical. Introvert somewhat longer than trunk. Surface of trunk smooth-seeming, as papillae covering it very small. Cephalon bearing dendritic crown of tentacles consisting of four main dichotomic branching trunks. Branches of tentacles pigmented with pinnules with violet grains. Smooth collar behind tentacles, with violet pigmentation. Zone of irregularly distributed large scalids behind cephalon. Longitudinal musculature of body wall not divided into longitudinal bands. Two retractors of introvert, both ventral, fastened to body wall in posterior third of body. Contractile
vessel with long, filiform, spirally twisted branches braiding internal organs. Intestine long, number of intestinal loops 16-20. Three fixing muscles, located individually for every animal. Anal opening level with nephridiopores. Wing muscles well-developed. No rectal
diverticulus found. Two nephridia fastened to body wall via mesenterial filaments along 1/4 of their length. Nephrida 80 percent as long as trunk (Ref. 1815). |
| Biology: |
Intertidal (Ref. 1815, 19 and 1840) to subtidal (Ref. 1815). Intertidal (Ref. 1815; 19 and 1840, page 149); subtidal species (Ref. 1815). |
| IUCN Red List Status: |
Not Evaluated (N.E.) Ref. 123251)
|
| Threat to humans: |
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| Country info: |
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