Paracheilinus nursalim Allen and Erdmann, 2008

Tea, Yi-Kai & Walsh, Fenton, 2023, Review of Australian Species of Paracheilinus Fourmanoir (Teleostei: Labridae), with Description of a New Species from the Great Barrier Reef and Coral Sea, Ichthyology & Herpetology 111 (3), pp. 397-415 : 411-413

Paracheilinus nursalim Allen and Erdmann, 2008

Nursalim’s Flasher Wrasse

Figures 12A–F

Paracheilinus nursalim Allen and Erdmann, 2008: 181 (holotype NCIP 6327 , Triton Bay , West Papua, Indonesia); Michael, 2009: 284 (field guide, underwater photograph from Bird’s Head Peninsula , West Papua, Indonesia) ; Kuiter, 2010: 109 (field guide, underwater photographs from Raja Ampat and Triton Bay, West Papua, Indonesia) ; Allen and Erdmann, 2012: 708 (field guide, underwater photographs from Triton Bay , West Papua, Indonesia) .

Diagnosis.— Dorsal-fin rays IX,11; anal-fin rays III,9; pectoral-fin rays 14; pelvic-fin rays I,5; pored lateral-line scales 11– 16 þ 3–10 ¼ 14–26; gill rakers 4–6 þ 8–9 ¼ 12–15; body depth 2.9–3.6 in SL; head length 2.8–3.3 in SL; snout length 3.8–4.9 in HL; orbit diameter 3.0– 4.2 in HL; interorbital width 3.9–5.3 in HL; least depth of caudal peduncle 2.0– 2.5 in HL; caudal peduncle length 1.5–2.3 in HL; TP males with 3–6 (rarely 3) elongate, yellow filamentous dorsal-fin rays (bright white when in display), longest dorsal-fin soft ray 1.8–2.3 in SL; pelvic fin length 1.6–2.0 in HL; caudal fin of TP males with very pronounced filamentous lobes, with filaments sometimes greater than SL; caudal-fin length 1.6–2.4 in SL; caudal concavity 0.8–1.5 in SL; body with stripe pattern A’; body with two black rectangular epaulettes, one below spinous portion of dorsal fin, one along lower caudal peduncle (dusky in preservation); ground color of body yellow orange in life; central portion of caudal fin with intricate blue markings.

Remarks.— This beautiful species was previously known only from the western Bird’s Head Peninsula of West Papua, Indonesia, from Raja Ampat and Triton Bay ( Fig. 12D–F ). It has also been photographed in Ambon, approximately 500 km west of the Bird’s Head Peninsula ( Allen et al., 2016). The Ambon record was based only on a single photograph, and so it wasn’t clear if a viable population existed outside of the Bird’s Head Peninsula. The discovery of P. nursalim in the Timor Sea in northeastern Australia extends the known distribution of this species approximately 1,000 km south of Ambon, and approximately 1,200 km south of the Bird’s Head Peninsula. It is likely that the species occurs throughout this region but has escaped detection until recently.

Australian records of P. nursalim are based on specimens from Flinders Shoal, Timor Sea ( Fig. 12A–C ). Comparison of live photographs and a single retained specimen ( Fig. 12C ; NTM S.18257-001) agrees well with topotypical examples of P. nursalim on the basis of meristic data, morphometrics, dorsal- and caudal-fin morphology, and aspects of live and preserved coloration details. Comparisons were made with two paratypes of P. nursalim ( Fig. 12F ; AMS I.44190-001). Some of the Australian specimens appear to have the dorso-anterior black epaulette below the spinous portion of the dorsal fin reduced or absent completely, which is otherwise typical of this species ( Fig. 12A–B ). However, this pattern appears to vary even in specimens from Triton Bay ( Fig. 12E ). In all other aspects, they are inseparable from topotypical examples of P. nursalim . We attribute these differences in coloration to intraspecific variation, which is not uncommon for Paracheilinus .

Etymology.— Named nursalim at the request of Cherie Nursalim and Michelle Liem, who successfully bid to support the conservation of this species at the Blue Auction in Monaco on 20 September 2007, and who have given generously to support Conservation International’s Bird’s Head Seascape marine conservation initiative. The name honors their parents Sjamsul and Itjih Nursalim. The name nursalim is treated as a noun in apposition.

Figures

FIG. 12. Paracheilinus nursalim, images of live and preserved specimens from Flinders Shoal, Timor Sea, off Darwin, Northern Territory, Australia (A–C) and West Papua, Indonesia (D–F). (A) Flashing male in nuptial colors, aquarium specimen. Specimen not retained. (B) Male in resting colors, aquarium specimen. Specimen not retained. (C) Male in preservation, NTM S.18257-001, 53.1 mm SL, Flinders Shoal, Timor Sea. (D) Flashing male in nuptial colors, underwater photograph from Triton Bay, West Papua, Indonesia. (E) Male in resting colors, underwater photograph from Triton Bay, West Papua, Indonesia. (F) AMS I.44190-001, 46.0 mm SL, male paratype, FakFak Peninsula, West Papua, Indonesia. Photographs by K. Kohen (A); Y. K. Tea (B–C; F); E. Cheng (D); and L. Cheng (E).