Cherax doberai n. sp. Figures 14–20. Material examined. Holotype: male (MZB Cru), under rocks, wood, and among roots and in debris along banks of an unnamed creek in the Teluk Bintuni Regency, West Papua, Indonesia. Coll. local people, May 2019. The specimen was sent to Aquarium Dietzenbach by Maju Aquarium. Diagnosis. Carapace surface smooth. Eyes rather small, pigmented. Rostrum lanceolate in shape. No teeth or spines on marginal edges, just two indentations on one side of the rostrum, and three on the other. Marginal edge in the anterior quarter with two granules on the left side of rostrum and three on the other. Rostral carinae weakly developed. Chelipeds blueish-grey with some creamy yellow-white with white joints. Fingers with weakly developed hooked tips. Other walking legs creamy white with some blueish-grey. Lateral pleura becoming creamy blue-grey. Description of male holotype (Figures 14–16). Body and eyes pigmented (Figure 14). Eyes rather small, cornea slightly broader than eyestalk. Body subovate, slightly compressed laterally. Pleon slightly narrower than cephalothorax (width 11.7 mm and 12.3 mm, respectively). Rostrum (Figure 16C) broad in shape, reaching end of first antennular peduncle and about 1.4 times as long as wide (width 3.6 mm at base, length 5.2 mm). Margins slightly elevated, continuing in rostral carinae on carapace, almost straight in basal part. Acumen with anteriorly orientated granule. Marginal edge in anterior quarter with two granules on left side of rostrum and three on the other. Postorbital ridges weakly developed, with one small tubercle at anterior terminus fading at half of occipital carapace length. Surface between rostral carinae heavily pitted. Postorbital ridges about 1/4 of carapace length. Cervical and branchiocardiac grooves distinct, not setose. No granules or spines present at middle part behind cervical groove on lateral sides of carapace. Carapace (28.6 mm) surface smooth. Anterior margin strongly produced; rounded upper margin directed inward. Areola smooth, pitted, small; length, 10.3 mm; narrowest width, 4.5 mm. Length of areola 36.0% of total length of carapace (28.6 mm). Scaphocerite, broadest at posterior third, convex in distal part, becoming narrower in basal part; thickened lateral margin terminating in corneous spine, reaching ultimate segment of antennular peduncle. Left scaphocerite 4.3 mm long and 1.9 mm wide. Proximal margins setose. Antennulae and antennae typical for genus. Antennae about as long as body. Antennal protopodite smooth, without spine; basicerite with one small ventral spine. Mouthparts typical for genus. Epistome with subcordiform cephalic lobe anteriorly bearing triangular lanceolate cephalomedian projection constricted at base. Lateral margins of lobe not thickened; each lateral margin with group of 5–7 very small tubercles separated by smooth region. Central part smooth, not pitted, excavate. First pereopods (Figure 16A,B) equal in form, subequal in size, chela slightly gaping. Left cheliped 20.8 mm long, 5.2 mm high, and 8.8 mm wide. Right chelae 25.8 mm long, 7.0 mm high, and 11.2 mm wide, strongly compressed. Fingers shorter than palm (left dactylus 10.6 mm long). Dactylus broad at base (4.6 mm), tapering slightly toward tip. Tip with corneous tooth pointing outwards at an angle of 45 ◦. Cutting edge of dactyl with continuous row of 10 small granular teeth and 1 slightly larger granule. Ventral and dorsal surface of movable finger smooth with scattered punctuation. Fixed finger smooth, scattered punctuation, triangular, merging gradually into palm, ending in corneous, hooked tooth, parallel to x-axis of finger. Tips of fingers slightly cross when fingers clasp. Upper surface of palm practically smooth, slightly pitted, more densely pitted at margins. Fixed finger broader than dactyl at base (5.6 mm). Scattered, short setae present in posterior ventral part of fixed finger, reaching from palm to about one-third of cutting edge. Cutting edge of fixed finger with row of 12 rather small granular teeth at posterior half. Outer lateral margin of chelae smooth, no patch present. Row of 4–5 small mesial propodal granules at dorsolateral margin. Dorsolateral margins slightly elevated in the posterior half. Dorsal surface of carpus (8.7 mm) smooth, with slight excavation in middle part and with one weakly developed mesial carpal spine. Ventral carpal surface margins slightly elevated, not setose, and with fovea; inner margin with weakly developed ventral carpal spine and ventromesial carpal spine oriented at an angle of approximately 45 ◦. Merus (13.5 mm) laterally depressed in basal part; surface smooth; small dorsal meral spine present. Inner ventrolateral margin smooth; two ventral meral spines present: one at first third, one at mid-length, other at tip of anterior part. Ischium (8.8 mm) smooth with a row of six small tubercles at ventrolateral outer margin. Second pereopods reaching anteriorly to tip of scaphocerite. Propodus (7.3 mm) and dactylus (3.6 mm) slightly longer than fixed finger (2.6 mm), of same height. Cutting edge of dactyl and propodus with row of dense, short setae. Carpus (4.9 mm), smooth, slightly pitted. Merus 10.2 mm. Ischium (4.7 mm) about half as long as merus. Third pereopods overreaching second pereopods to mid-length of carpus. Fingers shorter than palm. Fourth pereopods reaching distal margin of scaphocerite. Dactylus (2.5 mm) with corneous tip; no setae present. Propodus (7.1 mm) more than two times as long as dactylus, somewhat flattened, carrying many stiff setae on lower margin. Carpus (4.8 mm) about twice as long as dactylus. Merus (9.0 mm). Fifth pereopods similar to fourth, slightly shorter. Dorsal surface of pleon smooth, with scattered pits; abdominal segments (1–5) with short setae present on caudal margins of segment. Pleon length 36.1 mm. Telson with posterolateral tiny spines; dense short setae present in posterior third; posterior margins setose. Uropodal protopod with two small distal spines on mesial lobe. Exopod of uropod with transverse row of posteriorly directed diminutive spines ending in small spine, posteriorly directed on outer margin of mesial lobe. Terminal half of exopod with small spines and short hairs, slightly corrugated. Endopod of uropod smooth. Short, scattered hairs present on posterior third of dorsal exopod. Posterolateral spine on outer margin present. Second spine on medial dorsal surface present, directed posteriorly. Color. The living animals (Figure 14A,B) are colored as follows. The individual male of Cherax doberai n. sp. has blueish grey with some creamy yellow chelipeds with white joints. Fingers with weakly developed orange hooked tips. Outer lateral margin of chelae with a dark blue band. Dorsolateral margins light blue. Other walking legs creamy white with some blueish grey. Five small and dark blue spots on both sides of lateral pleura. Lateral pleura becoming creamy blue-grey. Telson fan light creamy. Molecular phylogenetic results. Cherax doberai n. sp. is a distinct lineage with uncertain affinities (Figure 5). Cherax doberai n. sp. is well isolated from all other Cherax species included in our analyses, with an overall minimum sequence divergence (p-distance, 16S) of 5.3% from both C. monticola and C. nigli n. sp., supporting the morphology-based description of C. doberai as a new species. Systematic position. C. doberai n. sp. belongs to the northern species group lineage, now consisting of 35 species (please see the respective section for C. nigli n. sp. below for details). Systematic remarks. In comparison to all species of the northern group, Cherax doberai n. sp. is morphologically most similar to C. holthu isi and C. snowden. Cherax doberai n. sp. may be easily distinguished from both species by the coloration and pattern of live individuals (Figure 17), by the shape of the chelae (Figure 18), by the shape of the rostrum (Figure 19), and by DNA barcoding (Figure 5). Coloration comparison (Figure 17). The individual male of Cherax doberai n. sp. (Figure 17A) has blueish grey with some creamy yellow chelipeds with white joints. Fingers with weakly developed orange hooked tips. Outer lateral margin of chelae with a dark blue band. Dorsolateral margins light blue. Other walking legs creamy white with some blueish grey. Pleon blue-grey. Individuals of C. holthuisi (Figure 17B) from Lake Aitinjo are usually creamy orange; rarely, light blue animals appear in the shipments from the exporter as well. Individuals from Lake Ajamaru are usually brown to greenish black. The living animals of C. snowd en (Figure 17C) are colored as follows. Chelae dark green to light green or greenish-gray, distal part of the lower margin cream to orange. Tips of chelae orange. Cephalothorax dark green, light green, brown-green, sometimes blueish-green, fading ventrally to cream, beige, or orange. Pleon same color 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. Bright orange animals of C. snowd en (Figure 17D) are known from Sasnek, Distrik Sawiat, South Sorong Regency. Chelae comparison (Figure 18). In C. doberai n. sp. (Figure 18A), the dorsolateral margins have a row of poorly developed, slightly elevated mesial propodal granules at dorsolateral margin, in contrast to 15–16 well-developed propodal granules in both C. holthuisi (Figure 18B) and C. snowden (Figure 18C). In C. doberai n. sp., the chelae are 2.3 times longer than the movable finger, while in C. holthuisi the chelae are 2.4 times longer, and in C. snowden 2.5 times longer than the movable finger. In C. doberai n. sp., the chelae are 2.3 times as long as broad, in C. holthuisi 2.4 times, and in C. snowden 2.7 times as long as broad. Rostrum comparison (Figure 19A–C). The rostrum of Cherax doberai n. sp. (Figure 19A) is broad at the base, and lanceolate shaped. The rostrum of C. holthuisi (Figure 19B) is rather straight and triangular shaped, while the rostrum of C. snowden (Figure 19C) is triangular shaped but broader at the base. Rostral margins of C. doberai n. sp. with two granules on one side and three on the other side on anterior fifth of rostrum, while C. holthuisi and C. snowden both have one tubercal spine on one side and two on the other. The rostrum of C. doberai n. sp. is 1.2 times longer than broad, of C. holthuisi 1.6 times longer, and of C. snowden 1.4 times longer than broad. In C. doberai n. sp., the rostral carinae extend beyond the anterior postorbital ridges, while in C. holthuisi and C. snowden the rostral carinae are just reaching the anterior postorbital ridges. Ecology. The habitat of this species is not known. The catchers are keeping the exact location a secret. Distribution (Figure 20). Bird’s Head Peninsula, Teluk Bintuni Regency, West Papua. Common name. As the common name for this crayfish, we propose the Doberai Blue Crayfish. Etymology. This species is named after the Bird’s Head Peninsula or Doberai Peninsula (Semenanjung Kepala Burung/Doberai), the large peninsula that makes up the northwest portion of the island of New Guinea, where this species was found. It is proposed as a noun in apposition.

Published as part of Lukhaup, Christian, Eprilurahman, Rury & Rintelen, Thomas von, 2025, Seven New Species of Crayfish of the Genus Cherax (Crustacea, Decapoda, Parastacidae) from Western New Guinea, Indonesia, pp. 1-55 in arthropoda 3 (2) on pages 21-27, DOI: 10.3390/arthropoda3020010, http://zenodo.org/record/18484894