Munidopsis scotti
Munidopsis scotti Jones & Macpherson, 2007
- kingdom Animalia
- phylum Arthropoda
- subphylum Crustacea
- class Malacostraca
- subclass Eumalacostraca
- superorder Eucarida
- order Decapoda
- suborder Pleocyemata
- infraorder Anomura
- superfamily Galatheoidea
- family Galatheidae Samouelle, 1819
- genus Munidopsis Whiteaves, 1874
Overview
General Description
The carapace is longer than it is broad, and the dorsal surface has numerous short striae and interrupted transverse ridges on the posterior half of the carapace, each striae and ridge bearing short setae. The cervical groove is distinct, transverse depression in the anterior part of the cardiac region. The gastric region is moderately inflated, with a pair of well-developed epigastric spines, and 2-7 additional small gastric spines. The rostrum is moderately short, triangular, slightly upcurved and terminates at the end of the cheliped merus. The length of the rostrum is 0.4 time the length of the remaining carapace, and has a maximum width 0.25 times the carapace breadth. The lateral margin of the rostrum is ridged, and the dorsal surface has small short striae bearing longitudinal carina that are distally sharp and sweep proximally into the gastric region. The frontal margin is oblique, with a well developed antennal spine. The lateral margin has an anterolateral spine that is as long as the antennal spine. There is a second spine directly behind the anterior cervical groove that is larger than the first, followed by several spines and again by another spine directly behind the posterior cervical groove. There is a notch at each end of the anterior and posterior branches of the cervical groove.
The sternum is as long as it is wide, with a maximum width at sternite 7. Sternites 3-4 have some short granular striae. Sternite 3 is moderately broad, serrate and bilobed, separated by a notch and is about 1.5 times wider than long. Sternite 4 is narrow at the base of sternite 3 with granular margins, and about 3 times wider than sternite 3.
The pleon has some small granules. There are two elevated transverse ridges on segments 2 and 3, the anterior ridge being sharp. The postertior ridge is absent on segment 4. Segment 6 is without a produced posteromedian lobe and does not exceed the lateral lobes. The telson is composed of 8-9 plates, and has numerous granules. The two posterior plates combined are more than twice as wide as long.
The ocular peduncles are fixed. The cornea is ovate, with a greatest width clearly less than the width of the third antennal segment. The broad based eyestalk is mesiodorsally produced into a strong eye-spine that is laterally directed and shorter than the cornea when measured along the lateral margin, and is mesioventrally unarmed.
The basal segment of the antennule bears subequal distolateral and distodorsal spines. The distomesial margin is granular.
The basal segment of the antennal peduncle has a strong distomesial spine, whilst there is a ahort distolateral spine. Segment 2 has a strong distolateral spine.
The ischium of the third maxilliped has a flexor margin that is sharply ridged, and distally ends in a small spine, whilst the extensor margin has a small distal spine. The crista dentata has 20-22 denticles. The flexor margin of the merus bears 2 spines and several smaller denticular spines. The extensor margin ends in a well-developed spine.
The cheliped is longer than the carapace including the rostrum, squamose and each scale has short setae. The merus has distomesial, distodorsal and distolateral spines and some additional spines along the dorsal side. The merus is 0.5-0.6 times the carapace length and twice the carpus length. The carpus is slightly longer than high, with a well-developed mesial spine and several small distodorsal spines. The paml is slightly longer than the carpus. The fingers are nearly n1.5 times longer than the palm, distally spooned with crenulate ridges. The movable finger is slightly shorter.
The walking legs (P2-P4) are moderately long and slender, somewhat compressed laterally and decreasing in size posteriorly. They are squamose from the carpi to the dactyli, each scale with short setae. P2 is the longest, overreaching the end of the cheliped. P2 is more than 1.5 times the carapace length, with a merus about 0.7 times the carapace length and 4-5 times longer than broad. The merus is 2.5-2.8 times the length of the carpus, and 1.4-1.6 times the length of the propodus, with a dorsal margin of well-developed spines that increase in size distally. The ventral margin has a row of short spines. The carpus has a row of spines along the extensor margin, the distal ones the longest, and a lateral crest with granules. The propodus is 4 times as long as high and 1.4-1.6 times longer than the dactylus, with a row of well-developed spines along the extensor margin. The flexor margin ahs 2 minute distal spinules. The dactylus has a terminal claw that is short and moderately curved. The ventral margin is nearly straight, with 15-16 teeth that decrease in size proximally, each with slender seta. The ultimate tooth is slightly closer to the penultimate tooth than the end of the segment. The length of the P4 merus is 0.8 times that of P2. There are epipods on the chelipeds.
(Jones & Macpherson, 2007)
Ecology and Distribution
Distribution
Northeast Pacific, on Juan de Fuca Ridge, at 2,715 m depth (Jones and Macpherson, 2007).


