Holthuija, Ng & Forges, 2015

Ng, Peter K. L. & Forges, Bertrand Richer De, 2015, Revision of the spider crab genus Maja Lamarck, 1801 (Crustacea: Brachyura: Majoidea: Majidae), with descriptions of seven new genera and 17 new species from the Atlantic and Indo-West Pacific, Raffles Bulletin of Zoology 63, pp. 110-225 : 160

publication ID	https://doi.org/ 10.5281/zenodo.5384590
publication LSID	lsid:zoobank.org:pub:40BCDD62-D35E-46D1-95A3-2CC0DF219DEE
DOI	https://doi.org/10.5281/zenodo.5466807
persistent identifier	https://treatment.plazi.org/id/8DB52511-0A93-47A6-9382-6DFAF32A962C
taxon LSID	lsid:zoobank.org:act:8DB52511-0A93-47A6-9382-6DFAF32A962C
treatment provided by	Valdenar
scientific name	Holthuija
status	gen. nov.

Treatment

Holthuija View in CoL n. gen.

Diagnosis. Carapace ovate; dorsal surface inflated, regions distinct, covered by granules or spines; gastric and branchial regions clearly delimited by grooves ( Figs. 24–26 View Fig View Fig View Fig ). Intestinal region without median spine ( Figs. 24–26 View Fig View Fig View Fig ). Pseudorostral spines relatively long, diverging, forming a V ( Figs. 24 View Fig , 25 View Fig , 37D–J View Fig ). Supraorbital eave large, anterior part strongly expanded, foliaceous, margin convex; spine; antorbital spine long, sharp ( Fig. 37D–J View Fig ). Intercalated spine distinct, separated from supraorbital eave and postorbital spine by distinct gaps; postorbital spine strong, lobiform; hepatic region with 1 strong spine, much shorter than postorbital spine; 1 tubercle below ( Fig. 37D–J View Fig ). Lateral carapace margin with 3 large spines, 1 branchial spine ( Figs. 24 View Fig , 25 View Fig ). Posterior carapace margin with 2 distinct median spines ( Figs. 24 View Fig , 25 View Fig ). Eyes relatively long, slender, with ovoid cornea ( Fig. 37D–J View Fig ). Antennal flagellum short, slender. Basal antennal article longer than broad, rectangular; surface with several tubercles, with 2 spines distally; inner and outer lateral margins with low granules; proximal outer angle rounded; antero-external crested rim of antennular fossa overlaps distal part of basal antennal article by about a third of its width ( Fig. 40D–I View Fig ). Epistome slightly wider than long, anterior margin with 2 low lobes and granular extension below each; posterior margin composed of 4 rectangular plates separated by shallow fissures ( Figs. 40D–I View Fig , 42C–E View Fig ). Suborbital margin separated from basal antennal article and margin of postorbital tooth by fissures ( Fig. 40D–I View Fig ). Outer surface of third maxilliped covered by short setae; ischium subrectangular, slightly longer than broad; postero-external angle of merus relatively broad, “inserted” into shallower concavity on outer margin of ischium; antero-internal part of ischium rounded, auriculiform ( Fig. 46A–F View Fig ). Male chelipeds relatively short in adult males, surfaces of merus and carpus almost smooth; carpus elongate; propodus of palm elongated, not inflated, curved, smooth, palm longer than fingers; fingers long, slender, gently curved, with small basal gape when closed ( Figs. 24 View Fig , 25 View Fig , 54D–I View Fig ). Ambulatory legs relatively short, slender; merus without dorsal subdistal spine; dactylus elongate, curved, covered with long setae except for corneous tip ( Figs. 24 View Fig , 25 View Fig , 56C–G View Fig ). Thoracic sternum wide; surfaces of somites 5–8 with numerous rounded tubercles and granules; sternites 3 and 4 with obliquely longitudinal depressions; margin between sternites 2 and 3 demarcated by deep notch; anterior margin of sterno-abdominal cavity forming complete rim ( Figs. 50D–I View Fig , 52I View Fig ). Male abdomen subrectangular, with 6 free somites and telson; somites 3 and 4 subequal to or wider than somites 6 and telson ( Fig. 50D–I View Fig ). Male press-button abdominal locking mechanism submedian in position on sterno-abdominal cavity ( Fig. 52I View Fig ). Female abdomen dome-shaped, covering most of thoracic sternum. G1 long, relatively stout, almost straight or gently curved, distal part with scattered short setae ( Fig. 27 View Fig ).

Type species. Maia miersii Walker, 1887 View in CoL , by present designation.

Etymology. The name is derived from an arbitrary combination of the name Holthuis, with the genus name Maja . This honours the major contribution by the late Lipke B. Holthuis in resolving the convoluted nomenclature of the genus. Gender feminine.

Remarks. Six species are included in Holthuija n. gen. H. miersii ( Walker, 1887) , H. suluensis ( Rathbun, 1916) , H. pauli n. sp., H. cognata n. sp., H. aussie n. sp. and H. poorei n. sp. These species are all easily distinguished by their prominently foliate supraorbital eave, which is the most expanded in all the genera treated here. All species also have a strongly granulated carapace surface, epistome, suborbital and pterygostomial regions, third maxilliped, thoracic sternum and abdomen. The suborbital tooth is also sharply separated from the postorbital tooth by a distinct fissure; and the G1 is generally simple, with a simple distal part and only scattered short setae.