Cherax phing, Lukhaup & Eprilurahman & von Rintelen, 2024

Lukhaup, Christian, Eprilurahman, Rury & von Rintelen, Thomas, 2024, Two New Species of Crayfish of the Genus Cherax (Crustacea, Decapoda, Parastacidae) from Western and Eastern Indonesian New Guinea, Arthropoda 2 (4), pp. 264-293 : 279-287

Cherax phing n. sp.

Figures 11–14 .

Material examined. Holotype: male ( MZB Cru 5795 ), under rocks and among roots and in debris along banks of unnamed creek of the Kali Ombak River drainage basin, West Papua, Indonesia. Coll. Jumrah Sukawati, Ripa Maricel Nicolae, and local people. January, 2020. GPS (1 ◦ 02 ′ 41.8 ′′ S, 132 ◦ 15 ′ 51.9 ′′ E). Crayfish samples sent to us by KKCrayfish in Jakarta. Allotype: female ( MZB Cru 5796 ), same data as holotype. Paratypes: six males, four females ( MZB Cru 5797 ); four males, three females ( ZMB 33781 ); same data as holotype .

Diagnosis. Carapace surface smooth; three bigger spines and one small posterior to cervical groove on lateral carapace present. Eyes large, pigmented. Eyestalk slightly narrower than cornea. Rostrum lance-shaped with elevated, thickened margins, non-setose. Rostral margins with three prominent teeth on one side and two on the other. Posterior extensions of the rostral margins prominent. Postorbital ridges prominent with one acute spine at anterior terminus. Uncalcified patch on lateral margin of chelae of adult male, white, translucent. Propodal cutting edge with very few short setae in posterior part and one larger tubercle. Chelae dark blue, becoming whitish pale to creamy in the lateral part. Fixed finger and dactyl with hooked dark orange tips anteriorly. Dorsolateral margins of chelae slightly elevated in posterior third, same color as chelae. Other walking legs blueish, becoming creamy-blue posteriorly. Carapace blueish to green-creamy, and pleon blue-greenish with horizontal creamy bands.

Description of male holotype ( Figures 11 and 12A–C ). Body and eyes pigmented. Eyes not reduced, rather large; cornea globular, darkly pigmented, nearly as long as eyestalk; eyestalk slightly narrower than cornea. Body subovate, slightly compressed laterally. Pleon narrower than cephalothorax (width 25.7 mm and 28.6 mm, respectively). Rostrum ( Figure 12C ) broad in shape, reaching end of ultimate antennular peduncle and about two times as long as wide (width 6.8 mm at base, length 13.05 mm). Margins slightly elevated, continuing in rostral carinae on carapace, almost straight in basal part, distally tapering towards apex. Lateral rostral margin bearing three prominent teeth in distal half on one side and two on the other side, pointing upwards at angle of approximately 45 ◦. A few scattered short hairs present between the distal teeth and the acumen. Acumen with anteriorly orientated spine.

Rostral carinae extending as slight elevation posteriorly on carapace terminating at ending of postorbital ridges. Postorbital ridges well developed, terminating in spiniform tubercle anteriorly, fading at half of occipital carapace length, posteriorly. Postorbital ridges about one-sixth of CL. Cervical and branchiocardiac grooves distinct, non-setose; three small spines and one small tubercle present. Carapace surface smooth; ventrolateral margins rounded, slightly elevated.

Areola length, 21.7 mm; narrowest width, 10.3 mm. Length of areola 34.3% of total length of carapace (63.1 mm). Sparsely pitted.

Scaphocerite broadest at posterior third, convex in distal part, becoming narrower in basal part; thickened lateral margin terminating in corneous spine, slightly overreaching ultimate segment of antennular peduncle. Right scaphocerite 15.0 mm long and 5.1 mm wide. Rounded inner margin strongly covered by setae. Antennulae and antennae typical for genus. Antennae slightly longer than body. Antennular peduncle slightly overreaching acumen; antennal peduncle slightly overreaching tip of apex of scaphocerite. Antennal protopodite smooth, no spine, with row of hairs on inner margin; basicerite with one lateral and one ventral spine.

Mouthparts typical for the genus. Epistome with subcordiform cephalic lobe anteriorly bearing lanceolate cephalomedian projection constricted at base. Lateral margins of lobe not thickened; each lateral margin with two groups of 10–12 tubercles separated by the smooth central part. Central part smooth, not pitted, excavate.

First pereopods equal in form, chela gaping. Right chela 65.0 mm long, 12.7 mm high, and 26.5 mm wide. Left chelae ( Figure 12A,B ) 65.1 mm long and 13.1 mm high, 25.9 mm wide, strongly compressed. Fingers shorter than palm (right dactylus 21.5 mm long). Dactylus broad at base (11.6 mm), tapering slightly towards tip.

Tip with sharp, corneous, hooked tooth pointing outwards at an angle of about 45 ◦. Cutting edge of dactyl with continuous row of 9–10 small granular teeth and 1 slightly larger tooth at middle of cutting edge. Ventral and dorsal surface of movable finger smooth with scattered punctuation. No setae present. Fixed finger smooth, scattered punctuation, triangular, merging gradually into palm, ending in sharp, corneous tip. 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 (13.4 mm). Very few scattered short setae present in posterior ventral part of fixed finger, reaching from base to about one-third of fixed finger. Cutting edge of fixed finger with row of 4–5 rather small granular teeth at posterior half and 1 larger one at mid-length. Outer lateral margin of chelae with swollen soft and uncalcified patch (37.7 mm on the right chelae and 40.7 mm on the left chelae). Row of 9–10 mesial granules at dorsolateral margin. Dorsolateral margins elevated in the posterior third.

Dorsal surface of carpus (21.3 mm) smooth, with slight excavation in middle part and with a well-developed mesial carpal spine. Ventral carpal surface distal margins slightly elevated, non-setose and with fovea; proxilateral margin with well-developed ventral carpal spine and a prominent ventromesial carpal spine oriented at an angle of approximately 45 ◦.

Merus (31.3 mm) laterally depressed in basal part; surface smooth; small dorsal meral spine present. Inner ventrolateral margin with 8–9 small granules; three ventral meral spines present, one at mid-length, other in middle of anterior part, and third on distal ventrolateral inner margin.

Ischium (17.0 mm) smooth with one to two small spines at ventrolateral inner margin.

Second pereopods reaching anteriorly to approximately corneus spine of scaphocerite. Finger (7.5 mm) slightly longer than palm (4.6 mm), of same depth. A few scattered short setae present on dactyl and fixed finger. Cutting edge of fixed finger and carpus with row of dense, short setae. Propodus, 15.3 mm. Carpus, 12.0 mm, smooth, slightly pitted, slightly longer than propodus. Merus (20.4 mm) 1.7 times longer than carpus. Ischium (10.0 mm) about half as long as merus.

Third pereopods overreaching second by length of finger of second pereopods. Fingers shorter than palm.

Fourth pereopods slightly overreaching distal margin of scaphocerite. Dactylus with corneous tip. Short scattered setae present. Propodus (13.0 mm) more than 3 times as long as dactylus (4.0 mm), 1.6 times as long as carpus (8.0 mm); somewhat flattened, with many stiff setae on lower margin. Merus just slightly longer than propodus.

Fifth pereopods similar to fourth, slightly shorter.

Dorsal surface of pleon smooth, with scattered pits; abdominal segments (3–5) with short setae present on caudal margins of segment.

Telson with posterolateral spines; dense short setae present in posterior third. Posterior margins setose. Uropodal protopod with two distal spines on mesial lobe. Exopod of uropod with transverse row of posteriorly directed diminutive spines ending in one more prominent 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.

Description of female allotype ( Figure 13 ). Chela of first pereopods equal, 2.7 times as long as broad (30.0 mm and 10.9 mm, respectively). No soft patch in distal lateral margin of the chelae of females observed (n = 18). Mesial margin of palm slightly elevated, forming slender serrated ridge with row of 7–8 small granular teeth. Cutting edge of dactylus with 7–8 rather small granular teeth. Cutting edge of fixed finger with 10–11 small granules. Small scattered short setae visible along ventral cutting edges of chelae, denser and longer in ventral posterior area. Tips of fingers slightly cross when fingers clasp, not gaping. Cervical groove distinct, non-setose. Pleon just slightly wider than cephalothorax (widths 19.3 mm and 18.3 mm, respectively). Same color pattern as in males.

Size. The biggest male examined is the paratype with a carapace length of 75.5 mm and a total length of 160 mm; the holotype male has a total length of 136.4 mm, and the other animals have a total length of between 78.5 mm and 139.5 mm; the allotype has a carapace length of 42.6 mm and a total length of 94.0 mm (n = 18).

Color. The living animals ( Figure 14A–C ) are colored as follows. Chelae dark blue, becoming whitish pale to creamy in the lateral part. Fixed finger and dactyl with hooked dark orange tips anteriorly. Soft patch creamy-whitish. Dorsolateral margins of chelae slightly elevated in the posterior third, same color as chelae. Other walking legs blueish, becoming creamy-blue posteriorly. Carapace blueish to green-creamy, and pleon blue-greenish with horizontal creamy bands. Distal margin of tail fan brownish-red to orange. Females: same color as males, sometimes less intense. Some individuals show less bluegreen on the carapax and pleon and are more creamy colored.

Molecular phylogenetic results. C. phing n. sp. is part of a weakly supported clade also comprising C. gherardii , C. woworae , C. boesemani , C. pulcher , and C. wagenknechtae ( Figure 6 ). This clade is a sister group to a highly supported clade comprising C. warsamsonicus , C. mosessalossa , and a probably undescribed species of Cherax . C. phing n. sp. is well isolated from its closest relatives with a sequence divergence (p -distance) of 3.2% ( C. gherardii ), 2.2–2.4% ( C. woworae ), 3.9% ( C. boesemani ), 4.7% ( C. pulcher ), and 4.7% ( C. wagenknechtae ), supporting the morphology-based description of C. phing n. sp. as a new species.

Systematic position. C. phing sp. n. belongs to the northern species group lineage, now consisting of 28 species (please see the respective section for C. rayko n. sp. above for details).

Systematic Remarks

In comparison to all species of the northern group, the new species, C. phing n. sp., is most similar to the crayfish of the C. boesemani group including C. boesemani , C. pulcher , C. wagenknechtae , C. gheradiae , C. woworae , and two undescribed species in this group. C. boesemani is a species that is known from the Ajamaru Lake and surrounding creeks. C. wagenknechtae is known to be endemic to the drainage basins of the Beraur and Klasabun Rivers in the Western part of the Kepala Burung (Vogelkop) Peninsula, while C. pulcher is found in Hoa Creek and some other nameless creeks in and around Teminabuan. C. gherardiae Patoka et al. (2015) [ 6] is described as endemic to the Ajamaru Lake but we cannot confirm this information. In our expedition in 2010, we found this species in creeks on the road between Ajamaru and Teminabuan. No animals of this species were found in Ajamaru Lake at the time of our expedition, and the locals did not identify it from the lake either. As far as we know, the catchers deliberately spread false information to protect the fishing grounds, as the crayfish are sold to the pet trade. C. woworae was described from creeks close to the city of Teminabuan. In our expedition, we found it more south of the city of Teminabuan. In Teminabuan, just C. pulcher is present. Cherax phing n. sp. may be easily distinguished from the crayfish of the Cherax boesemani group by the coloration and pattern of live individuals, the shape of the chelae, the shape of rostrum, and using sequence divergence.

C. phing n. sp. differs from C. boesemani in the following characters: the shape of the chelae ( Figure 15 ) and the coloration ( Figure 16 ). While C. phing n. sp. has dark blue chelae, a blueish to green-creamy carapax, and a blue-greenish pleon with horizontal creamy bands, C. boesemani is usually purple-reddish with some black, sometimes blueish-orange, blue, or purplish-blue. In general, C. boesemani can vary in coloration depending on what river in the Ajamaru area they originate from. The palm is about 3 times longer than the dactyl in C. phing n. sp., while the palm in C. boesemani is about 3.5 longer than the dactyl. There is a row of 8–10 mesial granules at the dorsolateral margin of the chelae in C. phing n. sp., while there are 13–15 in C. boesemani . The dorsolateral margins are elevated in the posterior third in C. phing n. sp., while in C. boesemani , they are elevated in the posterior half. Three small spines and one small tubercle are present in the cervical groove in C. phing n. sp., while there are usually 0–2 spines present in C. boesemani .

C. phing n. sp. differs from C. wagenknechtae in the shape of the chelae ( Figure 15 ), the shape of the rostrum ( Figure 17 ), and the coloration ( Figure 16 ). While C. phing n. sp. has dark blue chelae, a blueish to green-creamy carapace, and a blue-greenish pleon with horizontal creamy bands, C. boesemani is usually purple-reddish with some black, sometimes blueish-orange, blue, or purplish-blue. C. wagenknechtae males from the Klasabun River drainage basin have light to dark red chelae with pink or creamy dorsolateral margins and a white patch. The anterior part is usually dark blue or black, more intensely colored. The corneous tooth on the tip of the fingers is orange. The cephalothorax is bright red to dark red to black, dorsally more intense, fading ventrally to light red or creamy. Segments of the pleon are dark red to bright red; the lateral pleura is lighter, becoming creamy-red. The walking legs are blue or gray-blue. The distal margin of the tail fan is brownish-red to orange. Animals from the village of Klamono (Beraur River drainage basin) differ in the coloration of the chelae. The chelae are dark blue to black, sometimes creamy-blue. The dorsolateral margins are light, creamy. These males usually also have orange or yellow rostral margins. The dorsolateral margins of the chelae are elevated in the posterior third in C. phing n. sp., while they are elevated in three-quarters of C. wagenknechtae . The granules of the dorsolateral margins of the chelae are very prominent in C. wagenknechtae , while in C. phing n. sp., they are smaller. Usually, 12–13 are present in C. wagenknechtae , while 8–10 are present in C. phing n. sp. The rostrum of C. wagenknechtae is clearly bent outwards at the base, while it is more straight in C. phing n. sp. The spines on the rostrum are more prominent in C. wagenknechtae .

Cherax phing n. sp. differs from C. pulcher in the shape of the chelae, the shape of the rostrum, and the coloration ( Figures 15–17 ).

The dorsolateral margins of the chelae are elevated in the posterior third in C. phing n. sp., while they are elevated in three-quarters of C. pulcher . The granules of the dorsolateral margins of the chelae are prominent in C. wagenknechtae , while in C. phing n. sp., they are smaller; usually, 10–12 are present in C. wagenknechtae , while 8–10 are present in C. phing n. sp. The rostrum of C. wagenknechtae clearly reaches or overreaches the end of the ultimate antennular peduncle, while in C. phing n. sp., it reaches about the end of the first antennular peduncle.

The coloration of C. pulcher is as follows. The chelae are light blue to dark blue, becoming white on the outer lateral margins. The elevated dorsolateral margins are blue. The anterior part of the cephalothorax is pinkish to strikingly pink, fading laterally to a greenish-gray. The dorsal pleon is dark blue to black, becoming pinkish-gray and pinkish at the margins. Older individuals are usually darker blue in coloration. As the distribution area of Cherax pulcher is very restricted, not many color variations of this species are known.

Cherax phing n. sp. differs from Cherax gherardii in the shape of the rostrum, the shape of the chelae, and the coloration ( Figures 15–17 ). The rostrum is 3.6 times as long as broad in C. gherardii versus 1.7–2.1 times in C. phing n. sp. The first chelae are 2.6–3.4 times as long as broad in C. gherardii versus 2.3–2.7 times as long as broad in C. phing n. sp. The coloration of C. gherardii is dark brown, marbled on the sides of the carapace with pale brown spots. The cervical groove and the distal end of the carapace are orange. The pleon has a prominent orange spot on both lateral sides on each pleomere. The soft distal part of the caudal fan is orange. The chelipeds are blue with orange joints; the palm of the propodus is blue in the basal part and pale in the distal part. The fingers are orange; the distal third is black with orange tips.

C. phing n. sp. differs from C. woworae in the shape of the rostrum, the shape of the chelae, and the coloration ( Figures 15–17 ). The rostrum is 2.0–2.5 times as long as broad in C. woworae versus 1.7–2.1 times in C. phing n. sp. The first chelae are 2.1–2.5 times as long as broad in C. woworae versus 2.3–2.7 times as long as broad in C. phing n. sp. The background color is steel blue, marbled on the carapace sides with numerous tiny pale spots. The soft distal part of the caudal tail fan is orange. The chelipeds are steel blue with pale joints. The palm of the chelae is steel blue.

Etymology. C. phing n. sp. is named in honor of Liauw Pauw Phing, a crayfish enthusiast, for his noteworthy contribution to the knowledge of the crayfish of Papua.

His continuing effort to search and find unknown species is very needed work for our better understanding of the crayfish of this region.

Ecology. C. phing n. sp. is endemic to the Kali Ombak River drainage basin in the western part of the Kepala Burung (Vogelkop) Peninsula, Southwest Papua, Indonesia ( Figure 18 ). One of the creeks harboring these crayfish is clear and shallow (0.2–1 m) with a fast to moderate flow and has a pH of approximately 5.5. The temperature is around 23–24 ◦ C. In most parts, no water plants are present. The substrate of the creek is rocky or sandy, with some parts covered with silt and detritus ( Figure 19 ). Crayfish hide in short burrows in the riverbank, under larger rocks, or in detritus that is present in all the parts of the creek. Big males have been observed as active during the day. In some villages, these crayfish are harvested for food by locals, but it seems that, even if they are collected for the pet trade and in some villages for human consumption, the population is stable. The creek is surrounded by dense forest. To improve the knowledge of the distribution of this species, more field surveys will be necessary.

Common name. As a common name for this crayfish, we propose the Green Hornet Crayfish, as it is already available under this name in the pet trade.

Figures

Figure 6. Phylogenetic relationships of C. phing n. sp. and C. rayko n. sp. within the northern New Guinea Cherax lineage, reconstructed by BI analyses of the 16S rRNA mitochondrial gene fragment. Numbers on branches show, from top, Bayesian posterior probabilities (>0.7) and ML/MP bootstrap values (>50). An asterisk indicates nodes with full support (1/100/100) in all analyses. The scale bar indicates the substitution rate. See Table 1 for information on the sequenced specimens.

Figure 11. Cherax phing n. sp., holotype male (MZB Cru 5795). Scale bar: 10 mm.

Figure 12. Cherax phing n. sp., holotype male (MZB Cru 5795). (A) Dorsal view of left chelae. (B) Ventral view of left chelae. (C) Dorsal view of carapace. Scale bar: 10 mm.

Figure 13. Cherax phing n. sp., allotype female (MZB Cru 5796). Scale bar: 10 mm.

Figure 14. Cherax phing n. sp., Kali Ombak River drainage basin. (A) Paratype male (MZB Cru 5797). (B) Paratype male color variation. (C) Paratype male color variation.

Figure 15. Chelae comparison. (A) C. phing n. sp. from Kali Ombak drainage basin. (B) C. boesemani from Ajamaru Lake. (C) C. wagenknechtae from Beraur River drainage basin. (D) C. pulcher from Hoa Creek in Teminabuan. (E) C. woworae. (F) C. gherardii.

Figure 16. Coloration comparison. (A) C. phing n. sp. with (B) C. boesemani from Ajamaru Lake, (C) C. woworae, (D) C. gherardii, (E) C. wagenknechtae from Beraur River drainage basin, and (F) C. pulcher from Hoa Creek in Teminabuan.

Figure 17. Rostrum comparison. (A) C. wagenknechtae from Beraur River drainage basin. (B) C. boesemani from Ajamaru Lake. (C) C. pulcher from Hoa Creek in Teminabuan. (D) C. phing n. sp. from Kali Ombak drainage basin. (E) C. gherardii. (F) C. woworae.

Figure 18. The Bird’s Head Peninsula, West Papua, Indonesia, with the Kali Ombak River drainage basin, the type locality of C. phing n. sp.

Figure 19. Kali Ombak River, habitat of C. phing n. sp.