Cirrhilabrus shutmani, Tea & Gill, 2017

Tea, Yi-Kai & Gill, Anthony C., 2017, Cirrhilabrus shutmani, a new species of fairy wrasse from the Babuyan Islands, northern Philippines (Teleostei: Labridae), Zootaxa 4341 (1), pp. 77-88 : 78-86

Cirrhilabrus shutmani n. sp.

Magma Fairy-wrasse

Figures 1–6 , 8A , Tables 1 –2

Holotype. PNM 15354, 55.7 mm SL male, northern Philippines, Cagayan province, Babuyan Islands, Didicas Volcano (19.08 N, 122.21 E), 50–70 m, rubble slopes, collected by M. Baghukan & D.G. Acutin, 25 August 2016.

Paratypes. AMS I. 47290-001, 44.2 mm SL male, WAM P.34787-001, 45.2 mm SL male, ZRC 55885, 39.5 mm SL male, all collected with holotype.

Diagnosis. Cirrhilabrus shutmani shares similar meristic counts to the other species in its complex, but differs from congeners in the following live colouration details: upper part of nape dusky red; dorsal and anal fin bright red with dusky markings; pelvic fins bright red, dusky, and unmarked; caudal fin bright yellow basally with distal half bright red.

Description. Dorsal-fin rays XI,9; anal-fin rays III,9; dorsal and anal-fin soft rays branched except first ray unbranched; last dorsal and anal-fin ray branched to base; pectoral-fin rays 15/15, upper two unbranched; pelvicfin rays I,5; principal caudal-fin rays 7 + 6, upper and lowermost unbranched; upper procurrent caudal rays 4–5 (5), lower procurrent caudal rays 4–5 (5); lateral line interrupted, with dorsoanterior series of pored scales 15/15–16 (15/16) and midlateral posterior peduncular series 6–8/6–8 (6/6); scales above lateral line to origin of dorsal fin 2– 3/2–3 (3/3); scales below lateral line to origin of anal fin 7/7; median predorsal scales 4; median prepelvic scales 6; rows of scales on cheek 2; circumpeduncular scales 16; gill rakers 3–5 + 8–9 = 11–14 (5 + 9); pseudobranchial filaments 7–9 (9).

Body moderately elongate and compressed, depth 3.5–3.8 (28.9) in SL, width 7.0–10.8 (7.0) in SL; head length 3.2–3.4 (3.2) in SL; snout pointed, its length 3.3–3.9 (3.3) in HL; orbit diameter 3.5–3.7 (3.5) in HL; depth of caudal peduncle 2.2–2.4 (2.2) in HL. Mouth small, terminal, and oblique, with maxilla almost reaching a vertical at front edge of orbit; dentition typical of genus with three pairs of canine teeth present anteriorly at side of upper jaw, first forward-projecting, next two strongly recurved and outcurved, third longest; an irregular row of small conical teeth medial to upper canines; lower jaw with single stout pair of canines anteriorly which protrude obliquely outward and are slightly lateral to medial pair of upper jaw; canine teeth in lower jaw followed by two smaller, conical teeth; sides of lower jaw with a series of small conical teeth, which continue across front of jaw behind canine; no teeth on roof of mouth.

Posterior margin of preopercle with 23–32 (32/32) very fine serrae; margins of posterior and ventral edges of preoperculum free to about level of middle pupil. Nostrils small, located anterior to upper edge of eye in a short membranous tube. Scales cycloid; head scaled except snout and interorbital space; 7 large scales on opercle; broad naked zone on membranous edge of preopercle; row of large, elongate, pointed scales along base of dorsal fin, one per element, longest about two-fifths length of spines, scales progressively shorter posteriorly on soft portion of fin; anal fin with similar basal row of scales; last pored scale of lateral line (posterior to hypural plate) enlarged and pointed; one scale above and below last pored scale also enlarged; horizontal series of greatly enlarged scales extend two-thirds distance to central posterior margin of caudal fin; pectoral fins naked except for few small scales at extreme base; single large scale at base of each pelvic fin, about three-fourths length of pelvic spine.

Origin of dorsal fin above second lateral-line scale, predorsal length 3.0–3.3 (3.3) in SL; first 1–3 dorsal-fin spines progressively longer, third and fourth subequal, fifth longest, 2.4–2.8 (2.4) in HL; interspinous membranes of dorsal fin in males extend beyond dorsal-fin spines, with each membrane extending in a pointed filament beyond spine; fifth dorsal-fin soft ray longest, 2.0–2.2 (2.0) in HL, remaining rays progressively shorter; origin of anal fin below base of ninth dorsal-fin spine; third anal-fin spine longest, 2.8–3.0 (3.0) in HL; interspinous membranes of anal fin extended as on dorsal fin; anal-fin soft rays relatively uniform in length, fifth longest, 1.6–1.9 (1.6) in HL; dorsal and anal-fin rays barely reaching caudal-fin base; caudal fin of TP males rounded, length 1.1–1.2 (1.2) in HL; pectoral fins short, reaching a vertical between bases of 5th or 6th dorsal-fin spines, longest ray 1.5–2 (1.5) in HL; origin of pelvic fins below lower base of pectoral fins; pelvic fins moderately long, but not reaching anal fin spine, longest ray 1.9–2.1 (1.9) in HL.

Colouration of male in life (based on colour photographs of the holotype and paratype when freshly dead, and aquarium photos of live individuals; Figures 1 , 3 , 4 , 5 & 8A ): head and body bright red to orange; lower part of head sometimes washed with magenta; lilac to magenta stripe weakly present from behind upper orbit to upper edge of operculum; second stripe of same colour weakly present from behind lower orbit to lower part of cheek; lilac to magenta stripes continue past eye anteriorly on to snout, the upper stripe reaching mid-upper lip; lower part of operculum sometimes washed with magenta; upper part of nape and sometimes narrow area below dorsal-fin dusky red; interorbital and upper part of snout sometimes with 3–5 fine white stripes; iris bright yellow to orange, dusky dorsally, with bluish grey submarginal ring around pupil; lower part of abdomen bright red to orange-red, sometimes washed with magenta; anterior two-thirds of body bright red, fading gradually to bright orange posteriorly; dorsal fin bright red with single row of large orange scales basally, often dusky anteriorly between first and second dorsal fin spines; more extensive dusky grey-red area sometimes present on anterior three quarters of fin; distal margin of fin narrowly bright blue to purple; anal fin similar to dorsal fin, but usually without dusky markings; caudal fin bright yellow, orange basally, with distal half of fin bright red; pelvic fins bright red, dusky anteriorly, narrowly bright purple-blue on leading edge; pectoral fins reddish hyaline.

Holotype Paratypes

PNM 15354 AMS I.47290-001 WAM P.34787- ZRC 55885

0 0 1

Colouration of initial phase in life (based on colour photographs and aquarium photos of live individuals): Similar to males; dorsal and anal fins hyaline red without dusky markings; pelvic fins hyaline red; caudal fin pale yellow hyaline at base, translucent to reddish hyaline distally.

Colouration in preservative; Figure 2 : similar to colour in life; dusky markings remain; red markings become pale tan; dorsal, anal and pelvic fins greyish hyaline; caudal fin greyish hyaline, base pale yellow; pectoral fins hyaline.

Etymology. Named in honour of Barnett Paul Shutman, who first provided photos as well as the type specimens of the new species (via Aquarium Iwarna, Singapore). The common name, magma fairy wrasse, alludes to its live colouration, as well as the type location of Didicas Volcano, an active volcano part of the “Pacific Ring of Fire” at the southern end of the Luzon Volcanic Arc.

Distribution and habitat. Cirrhilabrus shutmani is known only from the type locality, Didicas Volcano in the Babuyan Islands at the northern tip of the Philippines ( Figure 6 ). It appears to inhabit steep slopes comprised mostly of volcanic rubble at depths ranging from 50– 70 m.

Comparisons. Cirrhilabrus shutmani appears to be closely related to C. blatteus Springer & Randall (1974) , C. claire Randall & Pyle (2001) , C. earlei Randall & Pyle (2001) , C. jordani Snyder (1904) , C. lanceolatus Randall & Masuda (1991) , C. roseafascia Randall & Lubbock (1982) , C. rubrisquamis Randall & Emery (1983) and C. sanguineus Cornic (1987) . The nine species are distinguished from congeners in having the following character combination: relatively short pelvic fins (not or barely reaching anal-fin origin, except for C. claire with relatively long pelvic fins); a pair of stripes on head (in both sexes); and, dorsal and anal fins without obvious stripes or spots. Cirrhilabrus shutmani is readily distinguished from the other eight species in live colouration ( Figure 7–8 ; Table 2), and further from C. blatteus , C. earlei , C. lanceolatus , C. roseafascia and C. sanguineus in lacking a lanceolate caudal fin (however, see Remarks). Aside from live colouration, C. shutmani differs from C. jordani in having one fewer median predorsal scales (4 vs 5) and fewer lower gill rakers (8–9 vs 11). Based on Randall & Pyle’s (2001) morphometric data for similar-sized specimens of C. earlei , C. shutmani differs in having a shorter head length (29.3–30.9 vs 34.0–35.4 % SL), a smaller orbit (8.3–8.4 vs 8.9–10.2 % SL), a greater caudal peduncle depth (12.8– 13.3 vs 15.5–16.0 % SL), a shorter 1 st dorsal fin spine (4.8–6.0 vs 9.4–10.5 % SL), a longer anal fin base (28.3–29.4 vs 24.2–25.6 % SL), shorter first, second and third anal fin spines (4.6–6.2 vs 8.1–8.9; 8.6–10.0 vs 11.1–13.3; 9.7– 10.8 vs 12.8–13.5 % SL, respectively), shorter pelvic fin spine (7.7–8.3 vs 12.4–13.4 % SL) and shorter pelvic fin (14.4–15.8 vs 20.4–24.7 % SL).

Remarks. The live colouration and absence of a lanceolate caudal fin in C. shutmani should be treated as provisional. Members of the genus Cirrhilabrus are sexually dimorphic and protogynous, and often diagnosed by their terminal phase (male) colouration. Males of C. blatteus , C. earlei , C. jordani , C. lanceolatus and C. roseafascia often attain standard lengths greater than 70 mm, with total lengths frequently exceeding 100 mm (especially for C. lanceolatus and C. roseafascia ). The largest known specimen of C. shutmani is the male holotype, at 55.7 mm SL, leading us to believe that the specimens in the type series are not fully mature. Its close relationship with the other members of the species complex suggests that it may be capable of attaining greater lengths, and may develop a lanceolate caudal fin. In describing C. earlei, Randall & Pyle (2001) alluded to its small size (largest specimen 69.1 mm SL). B.D. Greene and R. Whitton later collected a specimen measuring approximately 100 mm SL (140 mm TL), showing that the species does attain lengths greater than previously thought ( Figure 9 ). The new specimen also possessed a strongly lanceolate caudal fin, a feature noted as absent in the original description of C. earlei . Whereas Tea et al. (2016) commented on the unreliability of using caudal fin morphology as a character for classification (indeed, C. claire , C. jordani and C. rubrisquamis lack a lanceolate caudal fin), the character might be expected in larger individuals of C. shutmani . In support of this, B. Shutman sent us a photograph of an aquarium specimen of approximately 65 mm TL that shows a weakly lanceolate caudal fin ( Figure 5C ).

We here provide new, previously unrecorded distribution records for C. claire , C. earlei , and C. lanceolatus ( Figure 6 ). Cirrhilabrus claire was previously known only from the type locality of Rarotonga, Cook Islands. It has since been collected and observed from Mo’orea, French Polynesia ( Figure 8I ). Cirrhilabrus earlei was previously known only from Palau. It has since been collected in Kwajalein Atoll, Marshall Islands, for the aquarium trade ( Figure 8B ) and by B.D. Greene (BPBM 39701). B.D. Greene, R.L. Pyle and J.L. Earle have also photographed and collected the species from across the Federated States of Micronesia, in Pohnpei ( Figure 9 ), Majuro, Puluwat (BPBM 40802), Gray Feather Bank, Ulithi and Yap. Cirrhilabrus lanceolatus was previously known only from Okinawa and the Izu Peninsula, Japan, but has since been collected from Scarborough Shoals, South China Sea, western Philippines, by aquarium fish collectors ( Figure 8F ).

In addition, we are aware of a Cirrhilabrus with a similar combination of colouration and fin-shape characters, photographed in the Ogasawara Islands ( Figure 10 ). Its live colouration details and differences from the other nine species are summarized in Table 2. Its nuptial colouration is very similar to that of C. shutmani (cf. Figures 8A and 10 ). Specimens are needed to evaluate the identity of this species.

Figures

FIGURE 1. Cirrhilabrus shutmani n. sp., freshly euthaniZed male holotype, PNM 15354, 55.7 mm SL, Didicas Volcano, Babuyan Islands, northern Philippines. Photo by S. K. Tea.

FIGURE 2. Cirrhilabrus shutmani n. sp., preserved male holotype, PNM 15354, 55.7 mm SL, Didicas Volcano, Babuyan Islands, northern Philippines. Photo by Y. K. Tea.

FIGURE 3. Cirrhilabrus shutmani n. sp., male holotype, PNM 15354, 55.7 mm SL, from Didicas Volcano, Babuyan Islands, northern Philippines. Image reversed. Photo by B. P. Shutman.

FIGURE 4. Cirrhilabrus shutmani n. sp., male, approximately 50 mm TL, from Didicas Volcano, Babuyan Islands, northern Philippines. Specimen not retained. Photo by B. P. Shutman.

FIGURE 5. Cirrhilabrus shutmani n. sp., males, A) approximately 57 mm TL, B) approximately 60 mm TL, C) approximately 65 mm TL, all from Didicas Volcano, Babuyan Islands, northern Philippines. Specimens not retained. Photos by B. P. Shutman.

FIGURE 6. Distribution records for selected species of Cirrhilabrus: closed star, C. shutmani; open circles, C. jordani; closed circles, C. earlei; closed triangles, C. lanceolatus; open triangles, C. roseafascia; open star, C. earlei + C. roseafascia; closed square, C. blatteus; open square, C. sanguineus; closed crosses, C. rubrisquamis; open crosses, C. claire.

FIGURE 7. Cirrhilabrus jordani, male, approximately 95 mm TL, aquarium specimen from Hawaii. Image reversed, specimen not retained. Photo by Y. K. Tea.

FIGURE 8. Males of selected Cirrhilabrus species. All are in nuptial display except D, F and I. A) C. shutmani n. sp., aquarium specimen from Didicas Volcano, Babuyan Islands, northern Philippines (photo by D. Laux); B) C. earlei, aquarium specimen from Kwajalein Atoll, Marshall Islands (photo by T. lauderdale); C) C. jordani, aquarium specimen from the Hawaiian Islands (photo by Y. K. Tea); D) C. blatteus, Israel, Gulf of Aqaba (photo by J. E. Randall); E) C. roseafascia, aquarium specimen from Coral Sea, Australia (photo by Y. K. Tea); F) C. lanceolatus, aquarium specimen from Scarborough Shoal, South China Sea, western Philippines (photo by B. P. Shutman); G) C. sanguineus, aquarium specimen from Mauritius (photo by H. Tanaka); H) C. rubrisquamis, aquarium specimen from the Maldives (photo by T. Lauderdale); I) C. claire, aquarium specimen from Mo’orea, French Polynesia (photo by Y. K. Tea).

FIGURE 9. Cirrhilabrus earlei, male, approximately 100 mm SL (140 mm TL), collected from Pohnpei, Micronesia. Photo by B. D. Greene & R. Whitton.

FIGURE 10. Unknown Cirrhilabrus, male, approximately 70 mm TL, A) not displaying, B) in nuptial display, photographed in the Ogasawara Islands. Photo by S. Kobayashi.