FISHERY BULLETIN: VOL. 73, NO. 1 



trophomeres rather than one or two per parasite. 

 It differs from T. fasciatus by being attached 

 to the dorsum of the host's thorax rather than 

 the ventral abdomen, by bearing multiple gono- 

 meres on each trophomere rather than one or 

 rarely two, and by having much shorter lengths 

 of the trophomeres (not including the gonomeres 

 — about half that of T. fasciatus). 



Description of Holotype 



Externally, the holotype consists of three tufts 

 of trophomeres attached to the dorsal carapace 

 (Figure 3). The prior existence of a fourth tuft 

 is indicated by a scar on the host's carapace. 

 Dense packing of the trophomeres and the appar- 

 ent loss of some by breakage during preserva- 

 tion and handling made it impossible to deter- 

 mine the exact number of trophomeres in each 

 tuft. Examination at 40 X magnification indicated 

 the followdng approximate numbers: 45 in the 



left anterior tuft, 20 in the left posterior tuft, 

 and 35 in the right posterior tuft. The tropho- 

 meres branch dichotomously close to the primary 

 stalk, which gives an appearance of many tropho- 

 meres arising directly from the primary stalk. 

 The trophomeres are of various lengths — 0.8 

 to 1.7 mm. Each trophomere (Figure 4a, b) is 

 composed of a short basal portion and one to 

 three gonomeres, usually three. A few tropho- 

 meres appear to have lost a fourth gonomere. 



The gonomeres (Figure 4) vary in shape from 

 oval to elongate; a few distal gonomeres are 

 small and cone shaped. The penultimate and 

 proximal gonomeres vary considerably in length 

 but are of similar diameter to the normal distal 

 gonomeres (0.25 to 0.32 mm). The dimensions of 

 15 distal gonomeres (measured in situ) are sum- 

 marized in Table 4. 



The host specimen, which was preserved in 

 ethyl alcohol, was partially dehydrated, brittle, 

 and broken at the third and fourth thoracic 



Figure 3. — Holotype of Thalasso- 

 myces albatrossi n.sp. on Stilomysis 

 major. A. Lateral view. B. Dorsal 

 view. 



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