Paramoguai kavieng, a new genus and species of camptandriid crab from Papua New Guinea (Crustacea: Brachyura)
Author
Ahyong, Shane T.
text
Zootaxa
2014
3856
4
578
584
journal article
10.11646/zootaxa.3856.4.6
dbe4c453-cd08-4ff9-8e31-dae0e6077a54
1175-5326
231590
80ABB2A3-8144-44AA-9C1E-575A1EB82B8F
Paramoguai
gen. nov.
Diagnosis.
Carapace subovate to pyriform, longer than wide, widest at branchial margins; lateral angles of posterior margin with prominent blunt projection; surface with scattered groups of short, dark, red-brown setae; mesogastric, cardiac, and intestinal regions each with prominent, upraised median protuberances. Front weakly bilobed, width about one-third fronto-orbital width. Suborbital margin well-developed, together with infraorbital margin forming shallow concavity (“cup”) on anterior surface. Maxilliped 3 rectangular, ischiomerus immovably fused, demarcation indicated only mesially by short suture; without median hiatus between inner margins when closed. Buccal margin of epistome bilobed, medially emarginated. Chelipeds monomorphic, more slender than walking legs, fingers without teeth on occlusal margins. Gonopod 1 strongly geniculate, deeply bifurcated forming two long branches. Abdominal somites 2–5 fused in males, 3–5 fused in females; somite
5 in
males strongly constricted proximally, partially exposing gonopod 1. Gonopod 1 strongly geniculate, distal recurved portion deeply bifurcated into 2 slender branches.
Species included.
Paramoguai kavieng
sp. nov.
(
type
species);
Paramoguai pyriforme
(
Naruse, 2005
)
comb. nov.
Etymology.
The name is a combination of the Greek prefix
para
- and generic name
Moguai
alluding to the similarity of the two genera. Gender: neuter.
Remarks.
Paramoguai
gen. nov.
belongs to the
Camptandrium
-like group of genera, united by a constricted male abdomen that partially exposes gonopod 1 and the markedly elongate branches of the bifurcated portion of gonopod 1 (
Manning & Holthuis 1981
;
Tan & Ng 1999
). Of these genera,
Paramoguai
resembles
Moguai
Tan & Ng, 1999
, sharing a proportionally elongate carapace and similar dorsal ornamentation (including a pair of posterolateral projections; “prongs” of
Tan & Ng 1999
), fusion of abdominal somites
2–5 in
males and
3–5 in
females, similar orbital structure with a suborbital “cup”, and monomorphic chelipeds.
Paramoguai
and
Moguai
are distinguished by the elongate carapace, which in all other camptandriids is as wide as or wider than long.
Paramoguai
differs from
Moguai
in having an immovably fused maxilliped 3 ischiomerus with evidence of separation only mesially (resembling the condition present in
Camptandrium
Stimpson, 1858
), in having a proportionally narrower carapace front (about one-third versus one-half fronto-orbital width in
Moguai
), in having the anterolateral margins of the carapace positioned slightly within the dorsal outline of the carapace, and in having a bilobed buccal margin of the epistome, which is distinctly medially emarginate rather than forming a prominent median tooth. This latter feature of the epistome margin, unique in the
Camptandriidae
, is evidence for the monophyly of
Paramoguai
.
Naruse (2005)
described
Moguai pyriforme
on the basis of female specimens from the Ryukyu Islands,
Japan
, recognising that it differed from
Moguai
sensu stricto
in having a narrower carapace front (about one-third frontoorbital width), a fused maxilliped 3 ischiomerus with only a short mesial suture, and anterolateral margins that lay within the dorsal outline of the carapace margins. His fig. 2B also indicates that the median buccal margin of the epistome is bilobed with a distinct median emargination.
Kishino
et al.
(2014)
provided a detailed supplemental account of
M. pyriforme
including male morphology.
Moguai pyriforme
clearly exhibits the diagnostic features of
Paramoguai
, to which it is herein transferred.