Notes On molluscan meiofauna from Plymouth

Abstract

Preliminary examination of marine meiofauna from the Plymouth area, especially on mesopsammic representatives, resulted in the finding of several typically interstitial Mollusca. Among them, Caecum glabrum, Hedylopsis spiculifera, and Philinoglossa praelongata were recorded live for the first time in the area. This is also the first record of Ph. praelongata outside the Mediterranean Sea.During a short stay at the Marine Biological Association Laboratory some preliminary studies on meiofauna were made. To obtain information especially about the interstitial fauna of marine sand, three typical samples of coarse sediment from different positions were examined.Sample A: Plymouth Sound, Outer Cawsand Bay, Queens Ground, 50°20' 03“ N, 4° 10' 27” W; ca. 6 fathoms (=11 m); coarse sand, about 6 1 examined (14 September 1982).Sample B: Plymouth Sound, southwest of Drake Island, 50° 21' 06“ N, 4° 09' 50” W; ca. 7 fathoms (= 13 m); coarse shell-sand, about 1 1 examined (15 September 1982).Sample C: outer Plymouth Sound, 50° 18' 51“ N, 4° 10' 30” W; ca. 12 fathoms (– 22 m); fine gravel, about 1 1 examined (15 September 1982).In this contribution only the gastropods are dealt with; other meiofauna will be treated ina later communication. The sole previous report of mesopsammic fauna from the Plymouth area is that of Spooner (1959). He examined two samples, one of which (Plymouth Sound) was taken fairlyclose to the above sample A, about 18“ more to the West at 4–5–5–5 fathoms (8–10 m; G. R. Forster, personal communication).