Harris: The copepod genus Porcellidium 
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Figure 2. Porcellidium rastellum sp. nov. Female: (A) antenna; (B) maxilliped; (C) maxillule; (E) PI; (F) mandible; (G) maxilla (^rake- 
like claw on endopod). Male: (D) antennule. Scale bar: A, B, E, F = 0.12 mm. C, D, G = 0.06 mm. 
Remarks. Porcellidium rastellum differs from most other 
members of the genus in the large areas of very small 
denticles that appear to be arranged in rows on the ventral 
(anterior) surface of the PI endopod. Another unusual feature 
is the way in which the anterior part of the cephalosome 
border is folded ventrally. This results in a portion of the 
hyaline border lying in a ventral position. However, this does 
not correspond to the condition in Tectacingulum because 
there is no modification of the hyaline border and only the 
anterior part of the border is reflexed. 
