extremity of the first unpaired lobe are observable. The appendage extends beyond the middle of the second sternite, but the specimen is probably stretched. In Hall's type, which is clearly contracted in the preabdomen, it extends to the middle of the fourth sternite.
No surface ornamentation has been observed except linear rows of high, circular scales on the proximal segments of the last two pairs of limbs.
| Measurements of type: | millimeters | |
| Length of carapace | 57.5 | |
| Width of carapace | 70 | |
| Length of eyes | 13 | |
| Length of metastoma | 32+ | |
| Anteroposterior length of coxa of last leg | 43 | |
| Length of swimming leg beyond carapace | 125 | |
| Length of preabdomen | 68+ | |
| Width of preabdomen | 74 | |
| Length of tergite | 15+ | |
| Length of operculum about | 25 | |
| Length of opercular appendage about | 52 | |
| Length of first postabdominal segment unknown; width of same about | 52.5 | |
Some measurements complementary to the preceding are afforded by the Litchfield specimen.
The metastoma is 30.4 mm long; 16.5 mm wide ad maximum and 11 mm at the posterior end.
The coxa of the last limb is 35.7 mm long on the inner side and 22.4 on the posterior. The swimming leg measures 128.7 mm; its eighth segment is so much contracted that the original length was about 130 mm.
The preabdomen is 53 mm long and 54 mm wide. The postabdomen measures 90 mm in length; it is 53 mm wide at its anterior end and 28 mm at its posterior end. The first sternite is 12.5 mm long, the last 19.5 mm. Of the telson 44 mm are preserved; its initial width is 15.5 mm.
