Research Article |
Corresponding author: Christian Lukhaup ( craykeeper@gmx.de ) Academic editor: Sammy De Grave
© 2015 Christian Lukhaup, Jörn Panteleit, Anne Schrimpf.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Lukhaup C, Panteleit J, Schrimpf A (2015) Cherax snowden, a new species of crayfish (Crustacea, Decapoda, Parastacidae) from the Kepala Burung (Vogelkop) Peninsula in Irian Jaya (West Papua), Indonesia. ZooKeys 518: 1-14. https://doi.org/10.3897/zookeys.518.6127
|
A new species, Cherax snowden sp. n., from the Oinsok River Drainage, Sawiat District in the central part of the Kepala Burung (Vogelkop) Peninsula, West Papua, Indonesia, is described, figured and compared with the closest related species, Cherax holthuisi Lukhaup & Pekny, 2006. This species is collected and exported for ornamental purposes and its commercial name in the pet trade is “orange tip” or “green orange tip”. Both species may be easily distinguished morphologically or by using sequence divergence, which is substantial, for considering C. snowden sp. n. to be a new species.
Crustacea , Decapoda , Parastacidae , Cherax snowden new species, freshwater crayfish, Oinsok River Drainage, Kepala Burung (Vogelkop) Peninsula, Irian Jaya, Indonesia, West Papua, pet trade
The crayfish of the island of New Guinea were extensively studied by
These species may easily be distinguished on the basis of sequence divergence or by their colour and colouration pattern.
The first specimens of the new species where exported from the city of Sorong, Indonesia as Cherax sp. in 2006. Those crayfish have been captured by a unknown local collector from Kepala Burung for ornamental purposes in West Papua, Indonesia and imported to Aquarium Dietzenbach /Germany through Maju Aquarium / Jakarta. Several animals from the first import were photographed and then preserved in 70% ethanol. Due to their colouration the first author named them Cherax sp. “orange tip” and “green orange tip”. In April 2015 we received another 6 animals through Garnelio, a leading german online store specialized in freshwater invertebrates from Mannheim, Germany. Furthermore, we recieved 20 additional specimens from Aquazone Indonesia a wholesalor for freshwater fish and freshwater invertebrates through Garnelio. The name of the crayfish collector in Sawiat District collecting for Aquazone Indonesia and other wholesaler in Indonesia is Irianto Wahid. According to the information obtained from Maju Aquarium and Aquazone Indonesia as well as from Irianto Wahid all specimens originated from creeks in the Sungai River Drainage. Two of the six animals obtained from Garnelio where photographed.All of them have been kept alive separately in aquarium tanks until samples of haemolymph were obtained for DNA analysis. After this procedure, the specimens were compared to the animals imported in 2006. They matched perfectly. They were subsequently preserved in 80% ethanol. One male from the shippment of April 2015 was selected as holotype, one female from the same shippment as allotype, another male as paratype.
DNA was extracted from muscle tissue using a standardized protocol (‘High Salt DNA Extraction Protocol for removable samples’;
Additional we have downloaded the following sequences from GenBank: HG942364 – Cherax (Astaconephrops) quadricarinatus (von Martens, 1868), KJ950502 – Cherax bicarinatus (Gray, 1845), KJ950510 – Cherax communis Holthuis, 1949, KJ950520 – Cherax holthuisi, KJ950526 – Cherax murido Holthuis, 1949, KJ950529 – Cherax paniaicus Holthuis, 1949, KJ950533 – Cherax peknyi Lukhaup & Herbert, 2008, KJ950507 – Cherax (Astaconephrops) boesemani Lukhaup & Pekny, 2008, KM501043 – Cherax sp. and as an outgroup we used NC_026214.1 – Euastacus spinifer (Heller, 1865) and HG799087 – Cherax destructor Clark, 1936. All sequences were aligned with Geneious. We used jModelTest (
Holotype: male (TL 96 mm) (MZB Cru 4291), Oinsok River Drainage, Sawiat District, Kepala Burung (Vogelkop) Peninsula, West Papua, Indonesia, collected by Irianto Wahid on 14 January 2015, exported through Aquazone Aquarium, Jakarta, Indonesia. Paratype: 1 male (TL 101 mm) (MZB Cru 4292), 1 allotype female (TL 77 mm) (MZB Cru 4293), same data as holotype.
3 males (TL 69–84 mm) (MZB Cru 4294), same data as holotype.
(Figs
Body subovate, slightly compressed laterally. Pleon narrower then cephalothorax (width 18 mm and 20 mm respectively). Rostrum (Fig.
Ventrolateral parts smooth with scattered pitts; anterior margin strongly produced, rounded upper margin directed inward. Dorsal surface of pleon smooth, with scattered pits; abdominal segments with short seate present on caudal margins.
Eyes rather large; cornea globular, darkly pigmented, about as long as eyestalk; eyestalk slightly narrower than cornea.
Antennulae and antennae typical for the genus. Antennae about as long as body. Antennular peduncle reaching slightly beyond acumen, antennal peduncle reaching slightly beyond apex of scaphocerite. Scaphocerite (Fig.
Epistome broadly triangular becoming lance-shaped,with corneous spine at anterior tip, lateral surface with small tubercles; central surface smooth, excavate. Mouthparts typical for the genus.
First pereopods equal in form, chelae not gaping. subequal in size, left cheliped largest (48 mm long, 18 mm wide, 10 mm high), probably replaced. Right chelae (Fig.
Merus (23 mm) laterally depressed in basal part; surface smooth and pitted; row of 6–7 tubercles present and a prominent spine at anterior part. Dorsolateral margin with one corneous tubercle; row of small granules on entire inner ventrolateral margin with 3 prominent spines at the anterior part. Ischium (12 mm) smooth with single granule on ventral surface.
Second pereopod reaching about to apex of scaphocerite. Finger as long as palm, of same height. Short setae present on dactyl and fixed finger, getting more dense anteriorly. Cutting edge of fixed finger and carpus with row of short setae. Carpus slightly longer than palm. Merus (15 mm) about 1.7 times longer than carpus (9 mm). Ischium (7 mm) about half as long as merus.
Third pereopod overreaching second. Fingers shorter than palm.
Fourth pereopod reaching distal margin of scaphocerite. Dactylus with corneous tip. Short setae present. Propodus more than twice as long as dactylus, about 1.5 times as long as carpus; somewhat flattened, carrying stiff setae on lower margin. Merus just slightly longer than propodus.
Fifth pereopod similar to fourth, slightly shorter.
Dorsal surface of pleon smooth in median region; pleura smooth, slightly pitted, becoming densely pitted on sixth somite and telson. Telson with posterolateral spines, dense short setae present in the posterior third. Posterior margines setose. Uropodal protopod with distal spine on mesial lobe. Exopod of uropod with two well defined spines. One distal spine on mesial lobe, with prominent median rib ending in a spine in middle of uropod. Posterior margin of proximal segment of exopod of uropod with row of small spines overlapping diaresis. Short seata present on posterior third of dorsal surface of endopod and exopod.Ventral surface of telson, endopod and exopod smooth, not pitted. Margines of exopod setose.
(Fig.
The males examined have a carapace length of 31–43 mm, and a total length of 69–101 mm (n = 5); the female has a carapace length of 34 mm and a total length of 77 mm (n = 1).
The living animals (Fig.
Cephalothorax dark green, light green, brown green, sometimes blueish green fading ventrally to cream, beige or orange. Pleon same colour as cephalothorax with transverse orange bands, pleura creamy to orange with a black, brown or dark green band. Walking legs from dark green to blueish gray or creamy yellow, sometimes brown yellow. Distal margin of tail-fan cream to orange.
Cherax snowden sp. n. differs from C. holthuisi in the shape of the rostrum, number of rostral teeth, the shape of the chelae and coloration. While C. holthuisi has just two indentations on each side in the distal part of the rostrum and no spines present, Cherax snowden sp. n. has 2 rostral teeth on each side near the apex. Cherax holthuisi usually is orange to pale, creamy or light brown, rarerly light blue, while the new species is dark green to light green or greenish gray. Tips of the chelae in the new species are striking orange. Eyes in C. holthuisi rather small compared to the eyes of C. snowden sp. n.
The phylogenetic tree revealed that C. snowden sp. n. forms a strong supported clade with an undescribed Cherax sp. individual that was collected in Sorong West Papua, Indonesia (GenBank accession number: KM501043). The two sequences in this clade differ by only 9 base pair substitutions (1.5%). The low genetic divergence of the undescribed Cherax sp. and the close geographic sampling origin indicate that this individual is the same species as the here new described species. The C. snowden sp. n. and Cherax sp. clade group next to the clade which includes Cheraxsp. nov. A and C. holthuisi. The species of these two neighbouring clades differ by 9.2% (Cherax sp. to Cheraxsp. nov. A) to 9.7% (C. snowden sp. n. to C. holthuisi), respectively. The strong genetic divergence of C. snowden sp. n. to the next related described Cherax species indicates that C. snowden sp. n. is indeed a new species.
C. albertisii; C. boesemani; C. boschmai Holthuis, 1949; C. buitendijkae Holthuis, 1949; C. communis; C. divergens Holthuis, 1950; C. gherardii Patoka, Bláha & Kouba, 2015; C. holthuisi; C. longipes Holthuis, 1949; C. lorentzi lorentzi Roux, 1911; C. lorentzi aruanus Roux, 1911; C. minor Holthuis, 1996; C. misolicus Holthuis, 1949; C. monticola Holthuis, 1950; C. murido Holthuis, 1949; C. pallidus Holthuis, 1949; C. paniaicus Holthuis, 1949; C. papuanus Holthuis, 1949; C. peknyi; Cherax pulcher Lukhaup, 2015; C. solus Holthuis, 1949.
The new species is named after the american freedom fighter Edward Joseph Snowden. He is honored due to of his extraordinary achievements in defense of justice, and freedom. The name is used as a noun in apposition.
Known only from tributary creeks to the Oinsok River, Sawiat District 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 has a pH of approx. 6.5. In most of the parts no water plants are present. The substrate of the creek is rocky, mostly covered with silt, stones and larger rocks..To improve the knowledge of the distribution of the species more collecting trips are necessary.
It is also necessary to briefly comment on the possible threats faced by the new species. As C. snowden sp. n. is collected in large numbers for the global aquarium trade, as well as for food for the growing local population, the crayfish population will invariably be adversely impacted. According to local collectors, the populations of the species have been decreasing in the last few years. Clearly, the continued collectiing of these crayfish for the trade is not a sustainable practice, and if the popularity of the species continues, a conservation management plan will have to be developed, potentially including a captive breeding program.
Theresia Sutedja and Sum Sum Kintajaya (Aquazone, Indonesia) are thanked for the support finding the location of this interesting species. Farschad Farhadi and Garnelio are acknowledged for the crayfish they sponsored.
Dennerle is thanked for sponsoring parts of the trip to West Papua. Herbert Nigl (Aquarium Dietzenbach) provided valuable information and sponsored the species. Finally, Charles Fransen and Sammy De Grave are acknowledged for helpful comments. We thank Nikson Solossa and Marten Luter Salossa for information on the habitat.