Memoirs of Museum Victoria 69: 259–267 (2012) ISSN 1447-2546 (Print) 1447-2554 (On-line) http://museumvictoria.com.au/About/Books-and-Journals/Journals/Memoirs-of-Museum-Victoria Two new species of Photonectes (Teleostei: Stomiidae) from the Indo-Pacific, and a re-examination of P. achirus Flynn, A. J.1,2,3 And KlepAdlo, C.4 1 The University of Queensland, School of Biomedical Sciences/Queensland Brain Institute, St. Lucia 4071, Queensland, Australia ([email protected]) 2 CSIRO Marine and Atmospheric Research, PO Box 1538, Hobart 7001, Tasmania, Australia 3 Museum Victoria, Ichthyology, PO Box 666, Victoria 3001, Australia 4 Marine Vertebrate Collection, Scripps Institution of Oceanography, University of California at San Diego, 9500 Gilman Drive, La Jolla, California, USA 92093-0208. ([email protected]) Abstract Flynn, A. J.and Klepadlo, C. 2012. Two new species of Photonectes (Teleostei: Stomiidae) from the Indo-Pacific, and a re-examination of P. achirus. Memoirs of Museum Victoria 69: 259–267. Two new species of the mesopelagic fish genus Photonectes (family Stomiidae) from the Indo-Pacific are described. Both are referred to the subgenus Photonectes because they lack pectoral fins, have no fleshy tissue on their dorsal- and anal-fin rays, have a pelvic-fin insertion closer to the caudal-fin base than the snout, and have IP photophores located on the isthmus at a position midway along the mandible, posterior to the mandibular symphysis. Photonectes waitti sp. nov., known from the tropical western and central Pacific Ocean, northwestern Coral Sea and north Indian Ocean, is most similar to P. coffea, differing from it by the number of PV photophores (24—25 vs. 29—31), gill filaments reduced (vs. greatly elongate), jaw teeth long and short canines (vs. short canines only), and barbel length less than (vs. equal to or greater than) head length. Photonectes paxtoni sp. nov., known from the tropical western Pacific Ocean, off Papua New Guinea, has a short barbel, less than head length, ending in a very large bulb without any terminal filaments or appendages, and different photophore numbers compared to other members of the subgenus: VAV 15—16 (vs. 10—15), AC 13 (vs. 9—12), and IV 29 (vs. 30—46). Photonectes achirus is re-examined with respect to previously unreported dark pigment on the head. Keywords Photonectes, Stomiidae, new species, Indo-Pacific Introduction located on the isthmus at a position midway along the mandible, posterior to the mandibular symphysis (Regan and The Stomiidae is a very speciose family of midwater fishes, Trewavas, 1930; Morrow and Gibbs, 1964; Klepadlo, 2011). currently comprising approximately 280 species in 27 genera Descriptions of these two species are provided herein. (Nelson, 2006; Eschmeyer, 2011; Froese and Pauly, 2011). Besides photophores and barbels, other dermal features The genus Photonectes has 25 nominal species, 16 of which that aid in identification of species of Photonectes include the are regarded as valid species (Eschmeyer, 2011; Froese and presence or absence of white luminous tissue patches on the Pauly, 2011). head and body and the presence or absence of ventro-lateral In 2009, 21 specimens of an apparently undescribed blue luminous tissue markings on the body, along the isthmus species of Photonectes were collected from the equatorial and inside the mouth. western Pacific Ocean, in the vicinity of Howland and Baker islands. In 2010, an additional specimen was collected in the Specimens of P. achirus were collected along with Coral Sea off Cairns, Australia. The examination of material specimens of the former undescribed species in the equatorial from museum collections revealed two more specimens, western Pacific Ocean in the vicinity of Howland and Baker extending the range of the species into Hawaiian waters and islands. While examining museum specimens of P. achirus, the Gulf of Aden. The search for additional material resulted patches of dark pigment were observed on the head that were in the discovery of another undescribed species collected in previously unreported (e.g., in Regan and Trewavas, 1930; 1969 by the Australian Museum off Papua New Guinea. Both Beebe and Crane, 1939; Morrow and Gibbs, 1964; Klepadlo, species are members of the subgenus Photonectes based on the 2011). The patches of dark pigment were only observed on faded lack of pectoral fins, their dorsal and anal fins not enveloped museum specimens, usually rusty-brown in colour, that had with fleshy tissue, their pelvic-fin insertion located closer to been preserved for a long period of time. The dark pigment was caudal-fin base than to the snout tip, and their IP photophores not detectable in freshly-caught specimens that were usually 260 A. Flynn & C. Klepadlo black or black-brown in color. Faded museum specimens of 11-301/-302 (2: both 48.5 mm SL), 0°27.568'—27.658'N, 176°51.848'— other Photonectes species were examined, but these markings 50.574'W, 28 February 2009, 12:32—13:32, neuston, 0—0.5 m depth; were found only on specimens of P. achirus. A re-examination NMV A 30906-001/-002/-003/-004/-005 (5: 31.6—51.0 mm SL), collected with holotype; NMV A 30908-001/-002 (2: 22.5—32.6 mm of P. achirus is provided on the basis of this new finding. SL), 0°21.243'—21.257'N, 176°50.117'—49.575'W, 23 February 2009, 12:17—13:17, neuston, 0—0.5 m depth; NMV A 30907-001/-002/- Methods 003/-004 (4: 25.2—30.7 mm SL), 0°54.289'N, 177°09.476'W, 02 May Values for selected morphometric and meristic features in the 2009, neuston net, 0—0.5 m depth; SIO 11-300 (37.6 mm SL), 0°13.518'—13.212'N, 176°46.428'—45.634'W, 19 February 2009, new species are given in Table 1. Measurements were made 07:43—08:43, neuston, 0—0.5 m depth; SIO 11-303 (2: 25.4—41.5 mm with vernier calipers to the nearest 0.1 mm and include: SL), 0°53.000'—50.586'N, 176°57.332'—56.657'W, 20 March 2009, standard length (SL), head length (HL), barbel length, and 12:59—13:57, neuston net, 0—0.5 m depth; USNM 402774 (32.3 mm lengths from snout to pelvic fin (Sn-V), from pelvic fin to vent SL), 01°19.045'—18.335'N, 176°47.913'—47.673'W, 19 April 2009, (V-vent), and from vent to base of caudal fin (vent-C). Percent RMT trawl M205, 1200 m depth; USNM 300149 (23.4 mm SL), of SL (% SL) was calculated for P. waitti and P. paxtoni and % 12°40'N, 51°13'E, 1 m plankton net, captured at surface, R/V Anton SL values for P. achirus were derived from Morrow and Gibbs Bruun Cr. 5, sta. 287A, IIOE Expedition, 3 February 1964; USNM (1964) and Froese and Pauly (2011). Descriptions of teeth are 300199 (26 mm SL), 21°20'—30'N, 158°20'—30'W, 26 September given and these were separated as premaxillary, maxillary, 1973, 3 m IKMT, 0—110 m depth, T. Clarke 73-9-33; USNM 300201 (24.8 mm SL), 21°20'—30'N, 158°20'—30'W, 30 August 1973, 03:18— mandibular, vomerine, palatine and basibranchial; maxillary 05:15, 3 m IKMT 0—350 m depth, T. Clarke 73-8-31. teeth are further divided into ”erect” (anterior canines) and ”oblique” (posterior series of very small inclined teeth). Diagnosis: Differs from other species in the subgenus Photophore terminology (Figure 1) follows Morrow and Gibbs Photonectes in the following combination of characters: (1964), Harold (2003), and Klepadlo (2011). In addition to dorsal-fin rays 11—14, anal-fin rays 12—16; IV photophores diagnostic counts of the primary photophores, descriptions are 38—39, PV photophores 24—25; absence of blue luminous given of small secondary photophores that occur as clusters or tissue; length of gill filaments on first branchial arch reduced, form lateral bars in the genus Photonectes. Further, less than depth of gill arch; and barbel with two large bulbs in descriptions are made of two opercular (OP) photophores: the series. Few species of Photonectes have more than one large pre-opercular photophore (PRO) at the posteriodorsal margin bulb or luminous area on the barbel (secondary photophores of the operculum and the subopercular photophore (SO) excluded). Above the main bulb in P. mirabilis are small bulbs located in a cup-like depression ventral to the PRO (notation on the stem and a tiny terminal bulb. P. phyllopogon has a follows Weitzman, 1974: Table 1). single bulb and a terminal luminous appendage (Morrow and Gill-filament length (Klepadlo, 2011: Fig. 2) on first Gibbs, 1964). P. barnetti has a large pale area along the stem branchial arch is defined as ”1st reduced” (less than one-half below the bulb (luminescent colour uncertain) (Klepadlo, arch depth), ”normal” (longer than arch depth but not extending 2011). P. coffea has two bulbs in series without any terminal beyond opercular opening) or ”very long” (much greater than bulb (Klepadlo, 2011). For P. waitti there are two large bulbs depth or arch and extending beyond opercular opening). in series and a tiny bulb at the end of the filament. Photonectes Most specimens were collected with a neuston net. Other waitti differs from P. mirabilis and P. phyllopogon in having collection methods included Isaacs-Kidd midwater trawl 11—14 dorsal-fin rays (vs. 16—17 and 20—23, respectively), (IKMT), IKMT modified to collect plankton (IKPT) 12—16 anal-fin rays (vs. 19—20 and 22—25, respectively), and (Williamson and McGowan, 2009), rectangular midwater trawl 38—39 IV photophores (vs. 33—34 and 30—31, respectively). (RMT) and a bottom trawl. Collection depths are given in meters It differs from P. coffea in having gill filaments on first gill (m), fathoms (fm) or meters-wire-out (mwo). Time of collection arch reduced (vs. very long, extending beyond gill opening), listed for P. waitti sp. nov. is given in UTC/GMT. Notes on the and PV photophores 24—25 (vs. 29—31). It differs from P. color (under visible light) of fresh specimens of P. waitti are achirus, P. caerulescens, and P. mirabilis in lacking blue based on observations made by the first author in the field. luminous tissue. Material examined is in the collections of the Australian Description: Body elongate, 20.9—71.4 mm SL; depth about Museum (AMS), Museum of Victoria (NMV), Scripps Institution eight times into length. HL 3.2—8.7 mm (11.0—18.1% SL, of Oceanography (SIO) and Smithsonian Institution (USNM). mean 15.3%); Sn-V 13.3—47.9 mm (58.5—67.4% SL, mean 62.1%); V-vent 3.4—10.5 mm (13.9—21.4% SL, mean 18.2%); Photonectes waitti new species vent-C 4.3—13.0 mm (15.6—23.4% SL, mean 19.9%) (see Table Figures 2a,b, 5; Table 1 1). Eye 0.8—1.9 mm (17.2—29.3% HL, mean 23.5%). Opercle concave dorsally and lobate posteriorly. Gill filaments on first Holotype: NMV A 30913-001 (71.4 mm SL), 0°34.836'—35.329'N, branchial arch reduced, length less than arch depth; tips of 176°56.432'—49.956'W, neuston net, 0—0.5 m depth, R/V Seward filaments dark. Color of body in life dark brown to black. On Johnson, Catalyst II expedition, 06 March 2009, 14:04—15:05. fresh specimens or undamaged preserved specimens, narrow Paratypes: AMS I.49494-010 (48.7 mm SL), 16°34.25'S, black lateral bands in line with PV, VAV and AC photophores. 147°08.01'E, 11 December 2010, 19:43—20:43, RMT8 trawl, 330 m depth; NMV A 30908-001/-002 (2: 22.5—32.6 mm SL), 0°21.243'- On freshly caught specimens, these lateral bands could be seen 21.257'N, 176°50.117'-49.575'W, 23 February 2009, 12:17—13:17, to harbor minute secondary photophores and luminous patches neuston, 0—0.5 m depth; NMV A 30915-001 (1: 32.1 mm SL) and SIO (described further below). Two new species of Photonectes (Teleostei: Stomiidae) from the Indo-Pacific, and a re-examination of P. achirus 261 Dorsal-fin rays 12 (11—14, rarely 15—16); anal-fin rays Teeth caniniform, long and short; premaxillary teeth 14 (12—16, rarely 17—19); pelvic-fin rays 7 (rarely 6); longest, needle-like. Premaxillary teeth 5—8; 4—8 maxillary pectoral fins absent. Dorsal and anal fins not covered with teeth erect and 4—10 oblique; mandibular teeth 11—25; black fleshy skin. Pelvic fins inserted closer to caudal fin than vomerine teeth in 2 to 3 pairs, lateral teeth longest; palatine to snout (33.1—42.4% SL vs. 58.6—67.4% SL); longest ray teeth in 2 pairs, about equal length; basibranchial teeth in 2 to 4 extending at least to anus (tips broken). Caudal fin forked and pairs (anterior and posterior pairs separated by gap, 1 to 2 pairs elongate; ventral lobe longer than dorsal lobe. All fin-rays followed by 1 to 2 pairs; posterior tooth in each group longest). covered with melanophores extending halfway along the Barbel shorter than head, 2.3-5.5 mm (59.0—85.4% HL, length; membranes clear. mean 74.0%), with two main bulbs and a fine terminal filament. Photophores: IV 38—39, rarely 35—37 (IP 12, rarely 11 or One specimen (SIO 11-304) with very tiny bulb at distal end of 13; PV 24—25, rarely 22, 23 or 26); VAV 13—14, rarely 12 or terminal filament. Stem pigmented, no secondary photophores; 15; AC 11—12, rarely 13; OA 38—39, rarely 35—37 (OV first segment (~45% of barbel length) tapering into first bulb 24—26, rarely 23; VAL 12—13, rarely 14—15), last 1 to 2 with pigment cup-like around bulb base. First bulb ovoid photophores over anal-fin base; BR-7, rarely 6. IP series (~18% of barbel length), width about three times stem width, beginning about halfway along isthmus length, approximately tapering into short segment of stem (~9% of barbel length) opposite BR-7; space between IP-8 and IP-9 about twice space followed by second bulb. Section of stem between bulbs with between IP-1 and IP-2 making series 8 + 4. Anterior end of AC melanophores increasing in concentration distally. Second series raised, approximately even with last VAL photophore, bulb elongate (~18% of barbel length), narrow, about twice tapering downward over anal fin base and ending along stem width, and with melanophore-line from stem extending ventro-lateral caudal peduncle. Secondary photophores on length of bulb onto short terminal filament (~9% of barbel head and body, mainly concentrated in vertical lines from length). In freshly-caught specimens bulbs lavender to pink dorsum to each PV, VAV and AC photophore; also between IV under white light. and OA series and along ventrum in rather horizontal lines; no Distribution: Known from tropical western and central Pacific secondary photophores on any fin-ray. Postorbital organ ovoid, Ocean, northwestern Coral Sea and Indian Ocean (Gulf of 0.7—0.9 mm (12.3—18.8% HL, mean = 14.6%; skin flap over Aden) at depths of 0—1200 m. posterior end in NMV A.30907-003. One ovoid PRO photophore; one smaller circular SO photophore. SO Etymology: Named in recognition of Theodore (Ted) Waitt, the photophore directed ventrally and placed in a cup-like founder of the Waitt Family Foundation and the Waitt Institute. structure. PRO and SO photophores of fresh specimens reddish The Waitt Institute sponsored and directed the expedition of the pink under visible light. Blue luminous tissue and dark R/V Seward Johnson to the equatorial western Pacific Ocean markings absent. (Catalyst II expedition) during which this species was collected. Figure 1. (A) Photophore notation: post – postorbital organ; VAV – ventrally, from pelvic fin base to anal fin origin; AC - from anal fin origin to caudal fin base; OV – laterally, from pectoral fin origin to pelvic fin origin; VAL – laterally, from pelvic fin origin to anal fin origin or slightly beyond; (B) and (C) IP – along isthmus to pectoral fin base commencing at mandibular symphysis or posteriorly halfway along isthmus length, respectively. 262 A. Flynn & C. Klepadlo Figure 2. Photonectes waitti new species a) NMV A.30906-005, 51.0 mm, paratype; b) lateral view of head and barbel, NMV A.30913-001, 71.4 mm, holotype. Photograph by NMV. Two new species of Photonectes (Teleostei: Stomiidae) from the Indo-Pacific, and a re-examination of P. achirus 263 Figure 3. Photonectes paxtoni new species, holotype, AMS I.1972043, 23.4 mm SL. Photograph by NMW. Figure 4. Photonectes achirus, AMS I.19739-018, 32.3 mm, lateral view of head of showing dark marking at upper operculum (Photograph by C. Klepadlo). 264 A. Flynn & C. Klepadlo Figure 5. Distribution of Photonectes waitti (black square), P. paxtoni (black circle), P. achirus (black triangle; white triangle = literature records). Symbols may represent more than one record Two new species of Photonectes (Teleostei: Stomiidae) from the Indo-Pacific, and a re-examination of P. achirus 265 Table 1. Selected meristics and morphometrics of Photonectes waitti, P. paxtoni, and P. achirus. Values for holotypes followed by range for paratypes in parentheses where they vary from the holotype. Values for P. achirus from Morrow and Gibbs (1964) and Froese and Pauly (2011). Photonectes waitti Photonectes paxtoni Photonectes achirus Character (n=24) (n=2) Standard Length (mm) 71.4 (20.9-74.0) 23.4 (22.4) 20.0-87.0 Fin Rays: Dorsal 12 (11-16) 16 (18) 14-16 Anal 14 (11-19) 18 (18) 14-19 Pelvic 7 (6-7) 7 7 Photophores: IP 12 (11-13) 8 8-11 PV 23 (22-26) 21 22-28 VAV 14 (12-15) 16 (15) 11-13 AC 11 (10-13) 13 10-11 OV 26 (21-26) 20 19-22 VAL 13 (12-15) 14 11-12 BR 7 (6-8) 8 6-8 %SL: Head 12.9 (12.1-18.9) 17.1 (15.6) 15.4-18.7 Sn-V 66.9 (58.5-67.4) 61.1 (61.6) 58.2-73.2 V-vent 14.7 (14.9-21.3) 15.4 (15.2) 8.7-21.1 Vent-C 18.2 (15.6-23.4) 23.5 (23.2) 15.6-22.8 Remarks: Photonectes waitti is a widespread tropical open- bulb, P. fimbria (synonym of P. parvimanus), can also be ocean species. Twenty-one specimens were collected in 2009 eliminated based on the following: IV photophores 43—49 (vs. from the equatorial western Pacific Ocean. One specimen was P. paxtoni with 29), IP photophores insert near mandibular collected in 2010 from Australian waters in the Coral Sea. symphysis or no gap (vs. insert halfway along the isthmus, or While examining older (40+ years) museum specimens labeled with gap), thick skin over dorsal- and anal-fin rays (vs. thick skin Photonectes sp., three additional specimens were found that absent), and bulb with terminal flap increasing with growth (vs. extended the distribution of P. waitti into the Central Pacific, in no flap or terminal appendage; growth change unknown). the vicinity of Hawaii, and the northwestern Indian Ocean Description: Body elongate, 22.4—23.4 mm SL; depth about (Gulf of Aden). seven times into length. HL 3.5—4.0 mm (15.6—17.1% SL); Sn-V 13.8—14.3 mm (61.1—61.6% SL); V-vent 3.4—3.6 mm Photonectes paxtoni new species (15.2—15.4% SL); vent-C 5.2—5.5 mm (23.2—23.5% SL) (see Figures 3, 5; Table 1 Table 1). Eye 1.0—1.1 mm (25.0—27.5% HL). Opercle lobate, slightly concave dorsally. Gill filaments on first branchial arch Holotype: AMS I.1970-243 (23.4 mm SL), 05°05'S, 145°56'E, off reduced, length less than arch depth; tips of gill filaments un- Madang, Papua New Guinea, 27 October 1969, 2 m IKMWT, 135 m pigmented. Color of body rusty-brown in preservative, assumed depth. black in life. Paratype: AMS I.19727-023 (22.4 mm SL), 05°05'S, 145°54'E, off Dorsal-fin rays 16—18; anal-fin rays 18; pelvic-fin rays 7; Madang, Papua New Guinea, 27 October 1969, 2 m IKMWT, 130 m pectoral fins absent. Dorsal and anal fins not covered with depth. black fleshy skin; fin-rays covered with minute white luminous Diagnosis: Photonectes paxtoni differs from other members of spots; membranes clear. Pelvic fins inserted closer to caudal the subgenus Photonectes in the following combination of fin than to snout tip (38.4—38.9% SL vs. 61.1—61.6% SL); characters: barbel short, with a very enlarged ovoid terminal longest ray extending to anal-fin origin. Caudal-fin rays bulb lacking terminal appendages; absence of blue luminous broken; fin assumed forked. tissue; length of gill filaments on first branchial arch reduced, Photophores: IV 29 (IP 8; PV 21); VAV 15—16 (last 2 to 3 less than arch depth; and VAV photophores 15—16 (vs. 10—15), over anal-fin base); AC 13; OA 34 (OV 20; VAL 14, last two AC photophores 13 (vs. 9—12) and IV photophores 29 (vs. 30— photophores over anal-fin base); BR 8. IP series beginning 46). The bulb is remarkably large and plain (without filaments). posteriorly about halfway along isthmus length, opposite BR-8; The enlarged bulb is similar to P. ovibarba (synonym of P. photophores evenly spaced. Anterior end of AC series beginning braueri). However, P. paxtoni has no pectoral fins (vs. present, on same level as last VAV. Secondary photophores scattered with 2 rays each), IV photophores 29 (vs. 32—33), AC photophores over head and body, in clusters along dorsum, tapering ventrally 13 (vs. 10—12), and the bulb lacks any terminal appendage (vs. to between each OA photophore, continuing ventrally between bearing a small ovoid appendage). Another species with a large each IV photophore, and in clusters along ventral surface; none 266 A. Flynn & C. Klepadlo on any fin rays. Postorbital organ ovoid, elongate, about equal to opening; and barbel shorter than head length, with small bulb eye diameter. One PRO and one SO photophore on operculum, ending in a terminal appendage with a tiny bulb at tip. and one postorbital photophore. Specimen AMS I.1927-023 Re-Examination: Body elongate, largest recorded specimen with a pair of white luminous spots on snout between nostrils. 87.0 mm SL. Morphometric and meristic values for four Blue luminous tissue and dark markings absent. specimens collected from waters around Howland and Baker Teeth caniniform, long and short; premaxillary teeth islands were in agreement with Morrow and Gibbs (1964): longest, needle-like. Premaxillary teeth 4; 5—7 maxillary teeth body depth 11.8—16.7% SL; head 15.4—18.7% SL (mean erect and 8 oblique; mandibular teeth 12—15; vomerine teeth 14.8%); Sn-V 58.2—73.0% SL (mean 65.6%); V-vent 8.7— one pair; palatine teeth absent; basibranchial teeth 4 (one pair 21.1% SL (mean 14.4%); vent-C 15.6—22.8% SL (mean 20.1%). anteriorly and two single teeth midlength). Vomerine teeth long, Eye 7.7—28.8% HL (mean 20.7%). Opercle slightly concave length equal to longest premaxillary tooth. dorsally. Gill filament very long, feathery; extending slightly Barbel short, 1.5—1.8 mm (42.9—45.0% HL), with very beyond gill cover; tips of filaments uncolored. Color of body large ovoid bulb. Stem short, ~1.0 mm (~25% HL), pigment black, fading to rusty brown in preservative. tapering anteriorly onto base of bulb in a small V-shape; no Dorsal-fin rays 14—16; anal-fin rays 14—19; pelvic-fin secondary photophores on stem. Bulb large and simple, with no rays 7; pectoral fins absent. Dorsal and anal fins not covered appendages or terminal filaments; width ~1.0 mm. Color of bulb with black fleshy skin. Pelvic fins inserted closer to caudal in life unknown. fin than to snout tip; longest ray extending posteriorly to vent. Distribution: Known only from type locality off Madang, Caudal fin forked; ventral lobe longer than dorsal lobe. All Papua New Guinea; depth 130—135 m. fin rays covered with melanophores along full length; membranes clear. Etymology: The name recognises Dr. John Paxton for his many Photophores: IV 31-36 (IP 8—11 + PV 22—28); VAV contributions to the study of mesopelagic fishes and for his 11—13; AC 10—11; OA 30—35 (OV 19—22; [rarely 23] + VAL encouragement to the authors. 11—12 [rarely 9—10 or 13—15], last two photophores over Remarks: Photonectes paxtoni is currently known from two anal-fin base); BR 6—8. IP series begins about halfway along specimens from shallow collections (depth 130—135 m). They isthmus length, approximately opposite posterior most BR; IP were located among 46-year-old museum specimens labeled photophores noticeably smaller than body photophores. Photonectes sp. Anterior end of AC series raised, about one photophore diameter above last VAV, gently tapering to ventral profile. Photonectes achirus Regan and Trewavas, 1930 Secondary photophores very small, scattered over head and body; most densely clustered along dorsum; no secondary Figures 4, 5; Table 1 photophores on any fin-ray. Postorbital organ ovoid, with dark Material examined: AMS I.19739-018 (32.3 mm SL), 07°09.0'S, cap of melanophores along dorsal margin or with cluster of 148°52.0'E (western Solomon Sea), 110 m depth, 7 November 1969; melanophores at anterior margin; length up to 30% HL. AMS I.19753-037 (2: 25.3—30.9 mm SL), 05°51.0'S, 147°20.0'E Clusters of small white luminous spots on opercle. Blue (Papua New Guinea, Vitiaz Straits), IKMT, 0—110 m depth, 4 luminous patch under OV-1 to OV-2; two patches along November 1969; AMS I.24859-002 (78.0 mm SL), 33°43.0'—40.0'S, isthmus from symphysis to BR-1; pair of spots between eyes 152°03.0'—05.0'E (Australia, off Sydney, NSW), bottom trawl, and small spots dorsal to occipito-vertebral articulation 0—1135 m depth, 16 October 1984; NMV A 30906-006 (46.4 mm (“nape”); one pair anteriorly inside mouth; midventral stripe SL), 0°34.836'—35.329'N, 176°56.432'—49.956'W, neuston net, 0—0.5 m depth, 6 March 2009; NMV A 30917-001 (46.7 mm SL), from below pectoral fins to pelvic fins, with short transverse 0°14.213'—14.354'N, 176°45.843'—45.641'W, neuston net, 0—0.5m streaks alternating with serial photophores. depth, 19 February 2009; SIO 11-305 (72.2 mm SL), 01°11.503'— Teeth caniniform, long and short; premaxillary teeth 10.113'N, 176°45.152'—46.050'W, RMT, 600 m depth, 26 April 2009; longest, needle-like. Premaxillary teeth 7—12; 6—8 maxillary SIO 11-306 (83.5 mm SL), 0°20.264'—18.657'N, 177°02.297'— teeth erect and 7—10 oblique; mandibular teeth 17—22; 00.516'W, RMT, 600 m depth, 9 May 2009; SIO 70-333 (33.5 mm vomerine teeth 1 or 2 pairs; palatine teeth 1 pair; basibranchial SL), 19°11.0'—04.8'N, 125°12.7'45.0'E, 10 ft IKMT, 0—2000 m teeth 4 pairs (anterior and posterior pairs separated by gap: 1 depth, 13 September 1970; SIO 88-194 (21.4 mm SL), 24°40.5'N, or 2 pairs followed by 2 or 3 pairs). 76.16'W (Exuma Sound), IKMT, 200 m depth, 14 July 1986; SIO 88- Barbel shorter than head length (70.0—80.0% HL). Stem 197 (23.0 mm SL), 25°28.0'N, 78°07.3'W (Tongue-of-the-Ocean), IKMT, 200 m depth, 8 January 1987; USNM 300205 (36.7 mm SL), covered with melanophores, terminating in a small bulb, 21°10'N, 158°10'W, IKMT, 0—775 m depth, 8 November 1974, slightly wider than stem width, with a long slender terminal 12:35—17:12, T. Clarke 74-11-4. appendage ending in a small bulb at tip. Diagnosis: Photonectes achirus differs from other species in Comment on Pigmentation: In older, faded museum specimens the subgenus Photonectes in the following combination of small to large dark semi-circular patches on snout and upper characters: presence of blue luminous tissue in a band opercle (Fig. 4; see Discussion). The dark patches were observed extending from pectoral region to pelvic fins, with short on older faded specimens of P. achirus (AMS I.19739-018, SIO transverse streaks between OV photophores, and in patches on 70-333, SIO 88-194, SIO 88-197) on the snout between the sides of isthmus, under lower jaw and above end of maxillary; nostrils and on the upper opercle (see Fig. 4). They are circular length of gill filaments very long, extend beyond opercular to slightly ovoid in shape, contain darker spots and are bordered Two new species of Photonectes (Teleostei: Stomiidae) from the Indo-Pacific, and a re-examination of P. achirus 267 by heavy pigment. Examination of more recently collected expedition was supported by The University of Queensland (unfaded) specimens of P. achirus (SIO 11-305, SIO 11-306) did Deep Ocean Australia Project (ARC-linkage grant # not reveal the colouration observed in older (faded) specimens. LP0775179 to Prof. Justin Marshall). Alan Goldizen and David Several specimens did have clusters of secondary photophores Wheeldon (The University of Queensland) made collections at the upper opercular margin that are probably associated with of P. waitti and P. achirus on the second leg of the Catalyst II the dark spots. However, other areas on the body with secondary expedition. We thank M. Gomon and D. Bray (NMV) for their photophores were not surrounded by any dark patches. One support throughout this project and for use of NMV facilities. specimen of P. achirus (USNM 300205) had noticeable clusters M. Gomon provided valuable comments on a draft of this of white luminous tissue on the nape and along the opercular manuscript. We are grateful to J. Paxton (AMS) for bringing margin with no dark patches surrounding the clusters; snout the authors together and encouraging our research; R. tissue was damaged. The skin on the head of P. cf. gracilis Rosenblatt, P. Hastings and H. J. Walker, Jr. (SIO) for support (USNM 300157) is in very good condition with both secondary and encouragement, and for use of laboratory facilities. photophores and a large cluster of white luminous tissue at the upper opercular margin; there is no indication of dark patches. References Other faded Photonectes were examined for dark patches: P. albipennis (AMS I.22l809-030, SIO 73-149), P. braueri (AMS Beebe, W. and Crane, J. 1939. Deep-sea fishes of the Bermuda Oceanographic Expeditions. Family Melanostomiatidae. I.20305-013), P. caerulescens (SIO 76-6), P. margarita (SIO 69- Zoologica, N.Y., 24(6): 65-238. 354), P. mirabilis (AMS I.19739-018), P. parvimanus (SIO 10- Clarke, T.A. 1974. Some aspects of the ecology of stomiatoid fishes in 177), P. paxtoni (AMS I.19727-023, AMS I. 19702-043), P. the Pacific Ocean near Hawaii. Fisheries Bulletin 72(2): 337-351. waiiti (USNM 300149, USNM 300201); none showed any trace. Eschmeyer, W.N. (ed.). 2011. Catalog of Fishes. World Wide Web The significance of the tissue is unknown; it is not noticeable in electronic publication http://research.calacademy.org/ichthyology/ fresh specimens nor is it reflective or photogenic. In reviews of catalog/fishcatmain.asp accessed on 29 March 2011. dragonfishes ascribed to the family Melanostomiatidae by Froese, R. and Paul, D. (eds.). 2011. FishBase. World Wide Web Beebe and Crane (1939) and Morrow and Gibbs (1964), neither electronic publication (version 02/2011) http://www.fishbase.org/ work mentions these dark patches. Whether it occurs only on P. search.php accessed on 29 March 2011. achirus is unknown at this time. Harold, A.S. 2003. Melanostomiidae: scaleless dragonfishes, Pp. 907- 912. In: Carpenter, K.E. and Walker, R.W. (eds.), FAO Species Distribution: Known from western Atlantic and Caribbean, north Identification Guide for Fishery Purposes. The living marine Pacific near Hawaii and Tasman Sea at depths of 75—1400 m resources of the western central Atlantic. Vol. 2: Bony fishes part (Clarke, 1974; Froese and Paul, 2011; Morrow and Gibbs, 1964; 1 (Acipenseridae to Grammatidae). FAO, Rome. Sutton and Hopkins, 1996) and now recorded from the Klepadlo, C. 2011. Three new species of the genus Photonectes equatorial western Pacific Ocean in the vicinity of Howland (Teleostei: Stomiiformes: Stomiidae: Melanostomiinae) from the and Baker islands. Pacific Ocean. Copeia 2011(2): 201-210. Morrow, J.E., and Gibbs, R.H.Jr. 1964. Family Melanostomiatidae, Pp. Comparative material examined 351-510 In: Bigelow, H.B., Breder, C.M., Cohen, D.M., Mead, Photonectes albipennis (AMS I.22809-030, SIO 73-149). G.W., Merriman, D., Olsen, Y.H., Schroeder, W.C., Schultz, L.P. Photonectes braueri (AMS I.20305013). and Tee-Van, J. (eds.), Fishes of the Western North Atlantic. Vol. Photonectes caerulescens (SIO 76-6, USNM 256901). 1. Part 4. Yale University, New Haven. Photonectes cf. gracilis (AMS I.20941-010, USNM 300157). Nelson, J.S. 2006. Fishes of the World. John Wiley and Sons, New Photonectes margarita (SIO 69-354). York. Regan, C.T., and Trewavas, E. 1930. The fishes of the families Photonectes mirabilis (AMS I.19739-018) [re-identified as P. Stomiatidae and Malacosteidae. Danish Dana Expedition 1920- achirus]. 22 6: 1-143. Photonectes parvimanus (SIO 10-177). Sutton, T.T., and Hopkins, T.L. 1996. Species composition, abundance, and vertical distribution of the stomiid (Pisces: Stomiiformes) fish Acknowledgements assemblage of the Gulf of Mexico. Bulletin of Marine Science 59: 530-542. Curatorial assistance was provided by H. J. Walker, Jr. (SIO), Weitzman, S.H. 1974. Osteology and evolutionary relationships of the M. McGrouther (AMS), and S. Jewett (USNM). The first Sternoptychiae, with a new classification of stomiatoid families. author’s research was supported by The University of Bulletin of the American Museum of Natural History 153: 327- Queensland Research Scholarship and a Graduate School 478. Research Travel Grant from The University of Queensland. Williamson, M., and McGowan, J.A. 2009. The copepod communities We thank Ted Waitt and the Waitt Institute for the invitation to of the north and south Pacific central gyres and the form of take part in a voyage to the equatorial western Pacific Ocean species-abundance distributions. Journal of Plankton Research aboard R/V Seward Johnson (Catalyst II expedition) and this 32: 273-183.