September, 1999 
SCAMIT Newsletter 
Vol. 18, No. 5 
The abstracts of the presentations have also 
been made available on-line at 
http://www.futuralink.it/vannarotolo. 
NEW LITERATURE 
Nemerteans have proven to have a difficult 
taxonomy in many ways. Not the least of these 
is a basic disagreement between nemertean 
specialists on which characters have meaning 
in separating taxa. This provides a field ripe for 
a molecular based approach which can be used 
to either validate or refute morphologically 
based taxonomic hypotheses. Sundberg & Saur 
(1998) provide just such an analysis, dealing 
with lineids in the genera Riseriellus , Lineus, 
and Micrura. The outcome of their 
examination is directly applicable to local 
nemertean taxonomy as they found both 
“genera” Lineus and Micrura to be 
polyphyletic. Our local Lineus bilineatus is one 
of several species ascribed to the genus which 
are not in the same clade as the type species 
Lineus longissimus. If this analysis is 
confirmed by others, lineus will require a new 
genus or genera. We assume that the local form 
identified as L. bilineatus is the same as the 
European form of that name included in the 
present analysis. The authors similarly found 
Micrura species to be scattered between 
several clades, but as no local species were 
included in the analysis it is unclear how local 
members of the genus would be aligned. 
Further analysis of a broader spectrum of the 
many species described in each of these genera 
will be required to more completely resolve the 
issue. 
Larsen & Wilson (1998) shine a similar, if 
morphologically based, light on some of the 
characters currently considered as significant in 
defining families within the tanaids. They 
found, for instance that the number of uropodal 
articles in their new species was ambiguous 
because of partial fusion. The authors mention 
that tanaid family definitions are also difficult 
to apply because of problems in use of seta/ 
spine differentiations. Sieg, who is largely 
responsible for the current familial 
arrangement and definitions, did not use the 
seta/spine distinctions proposed by Watling in 
his family definitions, and efforts to do so lead 
to problems. The senior author is attempting to 
develop a better and more consistent separation 
between tanaidomorph families. In the present 
paper the family Paratanaidae has been 
redefined, and the status of the others declared 
unsatisfactory and in urgent need of re- 
evaluation. 
As in a paper mentioned in the last issue the 
methodology of cladistics is under continual 
review. Jenner (1999) and Jenner & Schram 
(1999) continue this trend and critically review 
the assumptions underlying several cladistic 
methodologies. The different results presented 
by workers using different sets of assumptions 
and different methods should hardly be 
surprising. It is however a bit disappointing to 
see in black and white just how method 
dependant the “objective and testable” 
approach of cladistics can be. Instead of a final 
great truth we are presented with a series of 
successively better approximations of the 
undisputed truth as methodological problems 
are discovered and counteracted. As an 
unregenerate “traditional” morphologist I must 
admit some satisfaction in having the clay feet 
of the cladistic god highlighted in this fashion. 
I have no doubt that as the methods mature and 
the weak or inappropriate ones are weeded out, 
the hope of a less subjective systematic 
technique will finally be realized. The authors 
point out quite effectively that we ain’t there 
yet, especially for phylogenetic reconstruction. 
The introduced seaweed Sargassum muticum 
hit our shores in the 70’s, and rapidly spread 
along the coast. It provided a new substrate for 
a host of small associates, mostly peracarids 
but also mollusks, bryozoans, urochordates, 
nemerteans, etc. Viejo (1999) examines the 
same algal species in northern Spain, where it 
is also introduced. She compares the biota of 
the invasive species with that of two local 
2 
