This is the second report dealing with the benthic Polychaeta collected on the continental shelf of the north-eastern Brazil (approximately between 9.º and 11.º of latitude south), by the Laboratorio de Ciências do Mar (formerly Instituto Oceanográfico) of the Universidade Federal de Pernambuco.
In the first one we discussed only the scale-bearing species (Nonato & Luna. 1969).
Data concerning the area sampled by the Laboratório de Ciências do Mar can be found in the papers of Cavalcanti
et al. and Mauksoone & Tinoco, 1967.
The present paper is about the scale-free species, in number of 71.
Almost all the smaller species we can expect to find in similar areas, seem to be absent here. This may be due to their actual rarity or, most probably, to their destruction during sampling and sorting.
The hard bottom prevailing in the area, which has a very rough surface, shaped by blocks and pebbles of calcareous algae and corals make the biological sampling a hard enterprise. It is particularly difficult to preserve the integrity of soft-bodied animals, such as the polychaetes, against the grinding action of the material inside the sampling devices.
We must remember this exceptional condition when judging the apparent scarceness of the polychaetes. If the worm fauna of that region seems, at the first approach, very poor, in reality it may be not.
In consequence we hope the use of improved methods of sampling will give far better results. The night fishing, with a submerged light, for example, may be a choice method to attract many species from the ground or from the otherwise unaccessible hide-outs.
From the 71 species, only one has been considered as new for the science.
Scoloplos agrestis sp. nov. approaches
S. robustus Rullier and
S. madagascarensis Fauvel, but differ from them by the number of the thoracic setigers (only 15) and by the number of acicular setae of the thoracic neuropodia (only 5 or 6).
The Eunicea is the best represented group, with 26 species; the commonest being
Eunice longicirrata Webster (108 specimens, in 19 stations).
Diopatra spiribranchis Augener and also
Hypsicomus elegans Webster are considered as good species.
Only two flabelligerids were caught in the whole area; one of them is a well preserved specimen of
Pherusa scutigera (Ehlers) and the other a damaged specimen of
Piromis sp.
The greatest part of the present species is believed to be similar to those found in the Caribbean area, as we should expect. But a few show a great similarity with Pacific and Indian species. Some of them, as
Glycera longipinnis Grube,
Onuphis litoralis Monro and
Vermiliopsis acanthophora Augener, agree closely with the available descriptions.