Friday, March 17, 2017

[Crustacea • 2017] Cherax warsamsonicus • A New Species of Crayfish (Decapoda, Parastacidae) from the Kepala Burung (Vogelkop) Peninsula in West Papua, Indonesia


Cherax warsamsonicus 
Lukhaup, Eprilurahman & von Rintelen, 2017 


Abstract
A new species, Cherax warsamsonicus sp. n., endemic to the Warsamson River drainage, in the western part of the Kepala Burung (Vogelkop) peninsula, West Papua, Indonesia, is described, figured and compared with its closely related species, Cherax misolicus Holthuis, 1949. The new species may be easily distinguished from C. misolicus by the shape of the rostrum, absence of setae on the rostrum, the shape of the chelae, the presence of 3-4 cervical spines and by using sequence divergence, which is substantial for considering C. warsamsonicus sp. n. to be a new species. The new species is collected and exported for ornamental purposes and its commercial name in the pet trade is Cherax “irian jaya”, Cherax “pink coral”, or Cherax “hoa creek“. Due to similar colouration it is often confused with the recently described Cherax pulcher Lukhaup, 2015.

Keywords: Cherax, Crustacea, Decapoda, morphology, New Guinea, Parastacidae, pet trade, taxonomy, Warsamson River


Figure 1. Cherax warsamsonicus sp. n. A holotype male (MZB Cru 4529) from the Warsamson River, South Sorong Regency B idem, side view. 

Diagnosis: Carapace surface smooth with four small spiniform tubercles posterior to cervical groove on lateral carapace. Eyes large, pigmented. Cornea slightly broader than eyestalk. Rostrum lanceolate in shape with excavated margins. Rostral margins with three prominent teeth. Rostral carinae prominent. Postorbital ridges prominent with one acute tubercle at anterior terminus. Uncalcified patch on lateral margin of chelae of adult male white, translucent. Propodal cutting edge with row of small granules and one large tubercle. Chelipeds blue and white with white joints. Fingers blue in distal third black with hooked tips. Other walking legs blue-gray. Pleon black with pinkish-red pattern. Lateral pleura lighter becoming greyish green.




Ecology: Known only from the Warsamson River and its tributaries, South Sorong Regency in the central part of the Kepala Burung (Vogelkop) peninsula. The creeks from where these crayfish have been collected are shallow (20–60 cm) with a moderate flow, the water is clear, and have a pH of approximately 6.5. In most of the parts no water plants are present. The substrate of the creek is gravel or sand and soil mostly covered with silt and detritus, stones and larger rocks (Fig. 10). Crayfish hide in short borrows in the riverbank, under lager rocks or in detritus that gathers in slower flowing parts of the creek or river. To improve the knowledge of the distribution of the species more field trips will be necessary.

Etymology: Cherax warsamsonicus sp. n. is named after the Warsamson River in West Papua where it seems to be endemic.

Common name: The common name of the new species in the pet trade is Cherax “irian jaya”, Cherax “pink coral”, and sometimes it is sold also as Cherax pulcher. Therefore we propose the name Warsamson River Crayfish as a common name for the new species.


Christian Lukhaup, Rury Eprilurahman and Thomas von Rintelen. 2017. Cherax warsamsonicus, A New Species of Crayfish from the Kepala Burung (Vogelkop) Peninsula in West Papua, Indonesia (Crustacea, Decapoda, Parastacidae).  ZooKeys. 660; 151-167.  DOI: 10.3897/zookeys.660.11847