Migmarma lustrum, new species

(Figs. 47–49)

Material examined. Holotype: male (15.7 × 13.9 mm) (ZRC 2010.0021), in base of leaf of sago palm ( Metroxylon sagu), inland sago swamp, moist secondary lowland forest, village of Lilinta, Misool Barat, Raja Ampat Province, Irian Jaya, Indonesia, D. Telmov & K. Cureke, 1 April 2009.

Diagnosis. Carapace somewhat trapezoidal; dorsal carapace surface uneven but not setose; epibranchial tooth distinct, separated by deep notch; posterolateral margins slightly divergent; outer surface of chela covered with small granules, those on margins relatively sharper, outer surface gently convex, not flat, ventral margin of palm concave; suture between male thoracic sternites 3 and 4 distinct; ambulatory merus short, broad; male pleon triangular, telson relatively elongate, not sunken into distal margin of somite 6; male pleonal somite 6 broad; G1 slender, gently curved, chitinous distal part long, relatively slender, subspatuliform, tip subtruncate.

Etymology. The name is derived from the Latin word for swamp or bog, “lustrum”. The name is used as a noun in apposition.

Remarks. Migmarma lustrum, new species, is morphologically similar to M. modestum except that the ventral margin of the cheliped palm is gently concave and the outer surface is not flat (Fig. 47E, F) (versus ventral margin almost straight and the outer surface flat in B. modestum; Fig. 45F); the male pleonal somite 6 is less broad (Fig. 47G, H) (versus proportionately broader in B. modestum; Figs. 45D, 46B); and most significantly, the G1 is more slender with the chitinous distal part distinctly more elongate (Figs. 48C–G, 49A–E) (versus G1 stouter with the chitinous distal part short and stout in B. modestum; Figs. 45G–K, 46C–H).