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New Records of the Fish Genus Grammatonotus (Teleostei: Perciformes: Percoidei: Callanthiidae) from the Central Pacific, Including a Spectacular Species in the Northwestern Hawaiian Islands1 Bruce C. Mundy and Frank A. Parrish2 Abstract: A second species of Grammatonotus from the Hawaiian Islands, ten- tatively identified as G. macrophthalmus Katayama, Yamamoto & Yamakawa (Callanthiidae), is recorded from French Frigate Shoals and the Northampton Seamount based on observations from a research submersible. In the absence of collected specimens, identification was made by comparing characters visible in video images with previously published images and descriptions. The fish were observed from 340 to 440 m at or near rocky habitats with crevices. All of the observations were near current-swept areas that supported gold coral (Gerardia sp.) colonies, although the fish were never seen within the colonies. A habitat feature important for both Grammatonotus and Gerardia, such as current or planktonic food supply, may therefore influence distribution of the fish. Exten- sive fish surveys conducted in comparable depths at other areas of the archipel- ago have not encountered this species, with one poorly documented exception from trawling surveys. Two other range extensions of Grammatonotus are in- cluded herein: Grammatonotus laysanus Gilbert from the Line Islands with a specimen collected at Christmas Island at 274 m and an unidentified Gramma- tonotus juvenile from the Tuamotu Archipelago at 705 m. Our examination of specimens and review of previous records of Grammatonotus indicate that this genus needs taxonomic revision. The fish fauna of the Hawaiian Islands is ored examples of one such species (Plate better known than that of any other Pacific I) tentatively identified as Grammatonotus island group. Despite this, species previously macrophthalmus Katayama, Yamamoto & Ya- unrecorded from these Islands continue to be makawa, 1982. The fish were encountered found. Many of these are small and/or deep- during submersible dives in the Northwestern water species from poorly sampled habitats. Hawaiian Islands but could not be collected. In this paper, we document spectacularly col- Our identification is therefore based on com- parisons of video images with published de- 1 Supported in part by an award from the National scriptions, illustrations, and photographs. Undersea Research Program’s Hawai‘i Undersea Re- The only previous reference found to G. search Laboratory to the NOAA Fisheries Honolulu macrophthalmus in the Hawaiian Islands is Laboratory’s Ecosystems and Environment Investigation. Fujii’s (1986) brief review of seamount fish Dives at the Northampton Seamount were funded by an award from the NOAA Ocean Explorations Initiative. biogeography, which includes the species in Participation in this cruise by B. Mundy was part of the a table with the annotation ‘‘ESC, HI’’ (for NOAA Fisheries Honolulu Laboratory Coral Reef Eco- the Emperor Seamount Chain and Hawaiian system Investigation multivessel 2001–2002 surveys of Islands). No other information was given. reef and reef-associated ecosystems in the Northwestern Hawaiian Islands. Manuscript accepted 22 July 2003. Given the scarcity of information on this 2 National Marine Fisheries Service (NOAA Fish- species, the publication of our observations is eries), Pacific Islands Fisheries Science Center, Honolulu warranted. Laboratory, 2570 Dole Street, Honolulu, Hawai‘i 96822. materials and methods Pacific Science (2004), vol. 58, no. 3:403–417 Work of the U.S. Government Observations were made during Hawai‘i Un- Not under copyright dersea Research Laboratory (HURL) Pisces 403 404 PACIFIC SCIENCE . July 2004 Figure 1. Locations in the Hawaiian Islands where Grammatonotus macrophthalmus has been observed from HURL Pisces submersibles (asterisks) and locations where other Pisces submersible fish census dives were conducted during 1997–2002. The number of dives and their combined depth ranges (meters) are given for each location. V submersible dives in the Northwestern with the precious corals and adjacent habitats. Hawaiian Islands (NWHI) (Figure 1) on 8–9 These dives were conducted in conjunction September 2001 at the east extension of the with another set of submersible surveys that French Frigate Shoals (FFS) platform (23 looked at fish assemblages at the same depths 55 0 N, 165 23 0 W) and on 20 September and in similar habitats at several other 2002 at the Northampton Seamount (25 Northwestern and main Hawaiian Islands lo- 16.9 0 N, 172 01.3 0 W). The dives (P5-455– cations (Figure 1). 456, P4-055) were conducted to survey Collections of fishes were not possible, so deepwater foraging areas of the endangered all counts and measurements were taken from Hawaiian monk seal, Monachus schauinslandi video images and are therefore approximate. Matschie. The FFS location contains a gold The images had no calibrated scale for mea- coral (Gerardia species) bed, where seals from surements. Therefore, morphometric data are the FFS colony are known to feed (Parrish expressed as proportions of a relative refer- et al. 2002), with colonies encrusting pin- ence measurement (typically standard length nacles spread over a 2-ha area. Submersible [SL], head length [HL], or postorbital length) surveys of this bed were conducted in 1998 taken in the same video frame. Measurements (one dive), 2000 (one dive), and 2001 (two were those given as diagnostic for Gramma- dives). The Northampton Seamount site is tonotus species by Katayama et al. (1982) and also a foraging area for seals (Brent Stewart, Anderson (1999), using landmarks specified Hubbs Sea World, pers. comm., October therein. Measurements were taken with di- 2002), but the deepwater habitat was unex- viders from individual frames on the video plored before the three dives of our 2002 screen and checked to the nearest 0.5 mm survey. All submersible dives lasted 6–7 hr against a ruler. Measurements were taken at the bottom. The dive objectives were to from only those frames that best showed a identify, count, and obtain size estimates of fish viewed either laterally for most measure- potential monk-seal prey species associated ments or dorsally for head, interorbital, and Central Pacific Grammatonotus . Mundy and Parrish 405 body widths, without foreshortening of the were seen together on 8 September 2001, and fish’s image from turning. Images in which three fish were seen individually on 9 Sep- individual fish were filmed at close range in tember 2001. The first sighting of the second the frame’s center were used to avoid image day was at the same location as the initial distortion at frame edges and to reduce mea- sighting and was possibly one of the in- surement error due to small image size rela- dividuals seen on 8 September. We therefore tive to measurement precision. Only two suspect that we observed four individuals at individuals were filmed adequately for mea- three sites within the same general area of the surements to be taken. Images of one of bank. these allowed us to obtain many body mea- On 20 September 2002, 12 individuals of surements, but the other allowed only head this species were found at a second location, measurements. Therefore, single values are the Northampton Seamount (Figure 1). The given for most body proportions, but a range first sighting at this location was of a single of values is given for some head proportions. individual at 440 m (9.5C) on a flat carbo- Grammatonotus specimens at the NOAA nate substrate (that at first appeared not to be Fisheries Honolulu Laboratory (nmfs) and near high-relief habitat). The fish took cover the Bernice P. Bishop Museum (bpbm) col- inside a small crevice as the submersible ap- lections were examined to obtain compara- proached. The substrate changed to a sheer tive data, as were photographs of G. crosnieri vertical wall, estimated to be over 100 m high, (Fourmanoir) provided by W. Anderson a few dozen meters away from the site of this (Grice Marine Biological Laboratory). first observation. A second sighting of the species on this dive occurred at a ledge and crevice on the wall face at 420 m (9.8C), just results up-current of a ridge with colonies of gold coral. One individual was again seen briefly as Observations it took cover under a small arch at the crevice Our first sighting of G. macrophthalmus was on the cliff face. Ten more individuals were of two individuals at FFS (Figure 1) at 352 m seen after the submersible moved up to 340 m by submersible pilot T. Kerby and F.A.P. (12.1C) and traveled downcurrent over flat The fish were obviously unlike any previously carbonate substrate at the top of the cliff face. seen during thousands of hours of submers- All of the fish were seen close to small crev- ible observations in the Hawaiian Islands at ices within which they took shelter. As with comparable depths, including previous sur- the first sighting of the species at this loca- veys in the same area. The most distinctive tion, no high-relief substrate was visible im- characteristics of the fish were their striking mediately adjacent to the crevices where the color patterns and elongated tails. The slow fish were seen, but the drop-off to the cliff movement of one of the fish stunned by was just beyond our range of vision. All of the bright light of the submersible enabled these individuals quickly hid in crevices so F.A.P. to record close-up video images with that video images could not be obtained at the submersible’s digital video system (Plate the Northampton Seamount. I). Examination of the video by the scientists aboard the R/V Ka‘imikai-o-Kanaloa in the Description evening after the dive led to unanimous agreement that the fish was not a species re- The sizes of the fish were not measured di- corded from the Hawaiian Islands in taxo- rectly but were approximately 20 cm total nomic reviews of the fishes available at that length and 12 cm SL.

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