Alpheid Shrimp, IX — Banner and Banner 
97 
THUNOR Armstrong 
Tbunor micros caphis Banner 
Figure 5 
Tbunor microscaphis Banner, 1959. Pacific 
Sci. 8(2) : 151-154, fig. 13 a-i. 
Tbunor sp. Banner, 1956. Pacific Sci. 10(3) : 
367-371, fig. 23. 
LOCALITY: 1 ovigerous female from BC 13, 
carapace length 4.9 mm. 
This specimen has a slightly longer scapho- 
cerite than the type specimen, a male from the 
Marshall Islands, and the female from Saipan, 
but the article is shorter than that of the male 
from Saipan. Except for the telson there is 
almost perfect agreement in other parts. 
In the three specimens previously described 
the tendency to develop dorsolateral ridges on 
the telson, leaving a median groove, was noted; 
on this specimen these ridges are pronounced 
and actually rise above and curl over the median 
groove. Because of the inward rolling of the 
posterior portion the terminal truncation of the 
telson, when seen in dorsal view, appears to be 
almost a point. Unlike telsons previously re- 
ported for the family, both the lateral and the 
terminal setae extend beyond the posterior lat- 
eral spines, which are very poorly developed, 
and lie along the dorsal ridges projecting over 
the medial groove. Only one of the four dorsal 
spinules normally found could be seen. The 
outer uropod, without a trace of the transverse 
articulation, also has its outer margin rolled 
upward, and the sutural spines seem to be lack- 
ing; the distal margin of this uropod bears a 
series of short movable spines. Both the outer 
and inner uropod bear many long setae; on the 
latter they are along the middle of the superior 
surface. 
This development of the telson may be found 
to be a characteristic adequate to separate this 
specimen as a new species; however, until more 
mature female T. microscaphis are studied, it 
seems more logical to consider this specimen 
as merely a more mature stage of the species 
already described. 
Fig. 5. Tbunor microscaphis Banner. Female from 
Canton Atoll. Telson and uropods : a, dorsal view; b, 
lateral view (at a slight angle). 
