Life in the Open Ocean. Joseph J. Torres

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СКАЧАТЬ rel="nofollow" href="#ulink_3252627f-49db-5dbc-b153-43aa83157234">Figure 3.17) Encounter zone – volume (cm³) Tentacular length (m) Tentacular volume (cm³) Tentacle density^b (ppm) Prey types Medusae Calycopsis typa Disc 3.17A 850 12 0.0942 110.20 Large prey – types unknown Stomotoca pterophylla Sphere 3.17B 900 000 2.4 0.0033 0.00 Medusae, other gelatinous spp. Aequorea macrodactyla Cone 3.17C 1 500 000 200 0.7697 0.53 Salps, ctenophores, pteropods, forams, medusae Laodicea undulata Disc 3.17C 175 18 0.0088 50.00 Small crustacea, larval fish Dichotomia cannoides Cone 3.17C 50 7.5 0.0019 36.80 Small crustacea types unknown Liriope tetraphylla Sphere 3.17B 220 000 3 0.0052 0.02 Heteropods, appendicularia, larval crustacea, juvenile fish Solmundella bitentaculata Cylinder 3.17B 2 0.1 0.0118 5000.00 Gelatinous species Aeginopsis laurentii Cone 3.17D 100 0.2 0.0471 476.20 No data Somaris spp. Cone 3.17D 2 0.3 0.0001 40.00 Small motile species, types unknown Pelagia noctiluca Cone 3.17C 8 700 000 24 0.1794 0.21 Salps, ostracods, ctenophores, polychaetes, copepods, fish Siphonophores Sulculeolaria spp. Cylinder 3.17E,F 257 000 243.2 1.0400 4.10 Copepods Forskalia spp. Cylinder 3.17E 434 000 88.2 0.2400 0.56 Copepods, amphipods, chaetognaths, molluscs, fish, fish eggs

^a See Figure 3.17 for cross‐reference to arrangement patterns of deployed tentacles.

^b The calculated space within the encounter zone occupied by tentacles

      

Figure 3.17 Patterns of tentacle deployment seen in medusae, siphonophores, and ctenophores. (a) Tentacles radiate from the body, filling a disk‐shaped space; (b) tentacles are somewhere within a sphere around the body; (c) tentacles stream behind the body, filling a truncated cone; (d) tentacles are held ahead of the body in a cylinder or truncated cone; (e) tentacles radiate from a long stem, filling a cylindrical space; (f) tentacles or tentilla form a nearly flat curtain. Some siphonophores may have encounter zones of this shape.

      Source: Madin (1988), figure 1 (p. 416). Reproduced with the permission of the Bulletin of Marine Science.

       Leptomedusae

      Aequorea macrodactyla (Figure 3.17c) are large, lens‐shaped, medusae that swim nearly continuously, trailing the tentacles behind the bell to form a conical volume. Tentacles extend to about 50 times the bell diameter. Prey stick to the tentacles of the swimming medusa and are conveyed to the mouth. Like Stomotoca, the prey of Aequorea are largely gelatinous and include medusae, ctenophores, pteropods, and salps.

Laodicea undulata have a flat shape with large numbers СКАЧАТЬ