Marratha, Ng & Clark, 2003

Ng, Peter K. L. & Clark, Paul F., 2003, Three new genera of Indo-West Pacific Xanthidae (Crustacea, Decapoda, Brachyura, Xanthoidea), Zoosystema 25 (1), pp. 131-147 : 133-134

Genus Marratha n. gen.

TYPE SPECIES. — Cycloxanthops angustus Rathbun, 1906 , by present designation.

ETYMOLOGY. — The genus is named after Mary J. Rathbun (1860-1943), the name derived from an arbitrary abbreviation of her name. Gender feminine.

DIAGNOSIS. — Carapace quadrate, regions well defined, with prominent grooves separating most regions; all regions appear swollen, with scattered granules, those on 2M and 3M arranged in uneven transverse rows, does not appear eroded or rugose. Front produced, separated into two broad lobes by prominent V-shaped cleft, margin uneven to sinuous, serrulate; separated from acutely triangular inner supraorbital tooth by deep V-shaped cleft; subparallel with frontal margin. External orbital tooth acutely triangular, confluent with subcristate anterolateral margin; anterolateral margin arcuate, with four low but prominent lobes, first smallest, margins of lobes prominently granular to tubercular. Posterolateral margin gently convex to almost straight, lined with tubercles. Chelipeds long, slender; outer surfaces rugose, appears partially eroded in parts; fingers elongate, slightly shorter than palm, tips sharp; larger chela with well-developed, broad molariform basal tooth on cutting edge of dactylus. Merus of ambulatory leg serrulate but not cristate. Lateral margins of fused male abdominal segments 3-5 entire, continuous; telson semicircular, lateral margins gently convex, tip rounded. Distal part of G1 with numerous long plumose setae.

REMARKS

The generic affinities of the type species Cycloxanthops angustus were first placed in doubt when Guinot (1968) suggested it probably belonged to another genus and Serène (1968) in compiling his checklist of Brachyura for the Indo-West Pacific region tentatively referred the species to Neoxanthops ? angustus . This species has a number of characters including the relatively quadrate and flattened carapace; form of the carapace areolation; structure of the anterolateral teeth and ambulatory legs that are so distinctive that this crab does not belong to Cycloxanthops or Neoxanthops as defined currently. Neither can it be assigned to any other known xanthid genera. Serène (1984) had already implied as much when he referred to the species as “Aff. Neoxanthops angustus ”. In its unique overall morphology, C. angustus has to be referred to its own genus.