Eiconaxius malaku, Poore, Gary C. B., 2017

Poore, Gary C. B., 2017, Synonymy and problematic species of Eiconaxius Spence Bate, 1888, with descriptions of new species (Crustacea: Decapoda: Axiidea: Axiidae), Zootaxa 4231 (3), pp. 364-376 : 368

Eiconaxius malaku sp. nov.

Axius (Eiconaxius) acutifrons . —De Man 1925b: 4, 15–16, 37–40, pl. 3 fig 5. Not Eiconaxius acutifrons Spence Bate, 1888 . Eiconaxius indonesicus Sakai, 2011: 280 –281.— Komai & Tsuchida 2012: 38. Nomen nudum.

Type material. Holotype: Indonesia, SE coast of Great Kei I., 5°56.5'S, 132°47.7'E, 595 m ( Siboga stn 266), from hexactinellid sponge; grey mud with coral and stones ( ZMA CRUS.D.202876, male, 7.6 mm—not examined).

Diagnosis. Rostrum 1.2 times as long as wide, with acute apex, lateral margins denticulate. Median gastric carina unarmed. Lateral gastric carina smooth, simple. Pereonite 6, posterior margin denticulate. Major cheliped palm, upper margin denticulate; lateral and mesial faces smooth; distolateral margin unornamented; fingers about half as long as upper margin of palm; fixed finger cutting edge with broad blade over proximal half, irregular beyond; dactylus cutting edge with basal tooth, distal convex blade. Minor cheliped, palm upper margin as long as greatest height, lateral and mesial faces smooth; distolateral margin with prominent triangular toothed lobe in gape; fixed finger cutting edge denticulate. Pereopods 3 and 4, dactyli spatulate, with row of marginal spiniform setae and few facial setae. Male pleopod 1 absent. Telson 1.6 times as long as wide, apex angular-truncate, with defined posterolateral corners.

Etymology. From the Indonesian province of Malaku where the Kei (or Kai) Islands are located (noun in apposition).

Remarks. Sakai (2011) based his diagnosis of Eiconaxius indonesicus on De Man’s (1925b) description and figures of a specimen identified as Axius (Eiconaxius) acutifrons . A holotype was designated but Sakai (2011) failed to state where it was lodged and thereby did not comply with ICZN Article 16.4.2. The holotype, type locality and the collection housing the holotype of a new taxon are specified above to overcome this issue.

De Man (1925b) described only the rostrum, telson, both chelipeds and pereopod 2 of the holotype. Sakai (2011) diagnosed E. acutifrons with three generic characters but nothing specific. His longer diagnosis of E. indonesicus was similarly largely generic. While saying that his new taxon was ‘clearly different’ he did not specify any characters that might separate the two species. Komai & Tsuchida (2012) believed on the basis of De Man’s (1925b) and Sakai’s (2011) descriptions that this taxon differs from E. acutifrons with which it had been confused. They illustrated the lectotype of A. (E.) acutifrons , enumerated differences between the rostrums and cheliped dactyli of E. acutifrons and E. indonesicus . The diagnosis above is based on a suite of characters that will distinguish all species of the genus.