Takeda & Miyake, 1968
Carapace convex in both directions, weakly divided into regions by narrow, shallow furrows, studded with spiniform granules of good size fringed with some setae. Antero-lateral border with four stout spines including one at external orbital angle; spines increasing size posteriorly, with third tooth being most strongly directed forward. Subhepatic region with one or two granules. Chelipeds heavy and quite unequal; larger palm remarkably swollen, with short, stout immovable finger. Ambulatory legs smooth, rather densely covered with stout setae of variable length; each carpus with a terminal spine. (Takeda, 1998)
Description of holotype: The carapace is strongly convex fore and aft, slightly so from side to side, and rather thickly covered with short setae mixed with longish ones; the surface is only slightly divided into regions by narrow, shallow interregional furrows and studded with scattered spiniform granules of good size, those granules or spinules becoming larger and sharper near the antero-lateral borders; the setae or hairs are rather short and stiff, arising mainly in tufts around those granules or spinules, otherwise a few arising singly. The front is slightly produced and cut into two rounded lobes by a V-shaped sinus, each lobe bearing a small but sharp lateral lobule. The supraorbital border is minutely granulated and bears two traces of notches, while the infraorbital border is armed with several spinules and bears an indistinct notch near the external orbital angle; the inner infraorbital angle is only slightly produced. The inner angle of the basal antennal segment is hardly reached the ventral prolongation of the front, its outer angle being raised nearly to the inner infraorbital angle; the second segment is short and stout, and the third is a little longer than the second, being provided each with one or two longish setae on the outer angles.
The antero-lateral border is armed with four stout spines including the one at the external orbital angle, those spines increasing in size from the first to the fourth; each spine is straight and directed forward, the third being more strongly directed forward. The subhepatic region is minutely granulated, one or two of which are slightly prominent. The postero-lateral border is strongly convergent, its dorsal surface being shallowly concave for the reception of the last ambulatory leg.
The chelipeds are short, heavy and quite unequal, the right one being larger; the merus is entirely concealed under the carapace; the carpus is armed with sharp spines interspaced with short and long hairs on its outer surface; the armatures of the smaller carpus are nearly like the larger one; the larger palm is very swollen and armed with spines on the outer surface, those spines somewhat being beaded to some longitudinal rows and diminishing in size near its lower surface; the smaller palm is not swollen; the armatures of the smaller palm are nearly like those of the larger one, but the spines are very accentuated, four spines on the upper border being the most prominent; the fingers of the larger chela are exceedingly short, stout and bear two molar-like teeth on each cutting edge, while those of the smaller one are sharply toothed.
The ambulatory legs are smooth and rather densely covered with short and long hairs; the merus is unarmed, while the carpus bears a terminal spine. (Takeda & Miyake, 1968a)
Type locality: Sani, Amami-Oshima, Japan.
Range: Japan - Amami-Oshima (Takeda & Miyake, 1968a).