New genera and new species of Hexapodidae (Crustacea, Brachyura) from the Indo-West Pacific and east Atlantic
Author
Rahayu, Dwi Listyo
Author
Ng, Peter K. L.
text
Raffles Bulletin of Zoology
2014
2014-07-04
62
396
483
journal article
10.5281/zenodo.5353945
2345-7600
5353945
4CF42744-861A-4635-9703-E6639CEBFAA9
Mariaplax mica
,
new species
(
Figs. 1J
,
37
,
38
)
Material examined.
Holotype
: female (6.7 ×
4.5 mm
) (
NMCR 39069
), PANGLAO 2005, station CP 2407,
9°41.3'N
,
123°48.5'E
,
Bohol
Sea
,
Philippines
, coll. M/V
BFAR
,
204 –256m
,
1 June 2005
.
Diagnosis.
Carapace subquadrate, about 1.5 times as broad as long; dorsal surface covered by tubercles; regions indistinct (
Fig. 37A
). Anterolateral margin arcuate; posterolateral corner with angled prominence over base of posterior pereopods (
Figs. 37A
,
38A
). Eye small, slightly movable, cornea globular (
Fig. 37C
). Pterygostomial region with row of oblique striae (
Fig. 37B
). Third maxillipeds relatively broad, almost completely covering buccal cavity (
Figs. 37B
,
38B
); ischium of third maxillipeds slightly expanded subproximaly, mesial margin oblique; combined length of dactylus, propodus and carpus shorter than that of merus and ischium; exopod narrow, 0.3 width of ischium, flagellum well developed. Chelipeds stout, unequal (
Fig. 37D
) pubescent, tuberculated; major chela with gap when fingers closed; minor chela with narrower gap between closed fingers. P2–P4 long, slender (
Fig. 37A
) covered by tubercles; merus of P4 3.6 times as long as broad; dactylus of P2 and P4 upcurved (
Fig. 37A
); outer surface of merus with longitudinal groove (
Fig. 37A
). Female thoracic sternum relatively broad (
Fig. 37B
), covered by tubercles; sternites 1 and 2 fused, separated from sternite 3 by distinct ridge; sternite 3 separated from sternite 4 by distinct tuberculate ridge laterally; sternoabdominal cavity not reaches base of sternite 3. Female abdomen wide (
Figs. 37B
,
38C
); somites 1 to 6 free, telson with rounded distal margin.
Colour.
In life, pinkish brown overall, with the tubercles on the pereopods dark brown (
Fig. 1J
).
Etymology.
From Latin
mica
, tuberculate, alluding to the heavily granular carapace and pereopods. Name is used as a noun in apposition.
Remarks.
Mariaplax mica
,
new species
, resembles
M. cyrtophallus
,
new species
, in the heavily granulated carapace and pereopods, a similar shape of the third maxilliped and the relatively long P2–P4. However, the carapace is distinctively more squarish in
M. mica
(
Figs. 37A
) while in
M. cyrtophallus
the anterolateral margin of the carapace is narrower, sloping to wider posterolateral margin (
Fig. 28A
). The P2–P4 are also proportionately longer and the granules on the carapace and pereopods are relatively larger in
M. mica
(
Figs. 37A
,
38A
versus
Figs. 28A
,
29I
).
They also appear to have different depth preferences:
M. mica
was collected from more than
200 m
while
M. cyrtophallus
was collected from shallow waters
15–
30 m
.
Type
locality.
Bohol
Sea
,
Philippines
.
Distribution.
Bohol
Sea,
Philippines
. Deep water,
204–
256 m
.