Discovery of Kryptophanaronalf redi (Pisces: ) at San Salvador, Baharnas, with notes on anomalopid light organs

John E. MeCosker California Academy of Sciences, San Francisco, California 94 118 U.S.A.

(Received fOI publication November 9, 1981)

Resumen: Se informa de la presencia por primera vez en las 8ahamas del Pez Linterna del Caribe. Probablemente se le encuentre en este mar con más frecuencia si se le busca sistemáticamente. Se discute la coloración de los ejemplares juveniles y la relación que existe entre el órgano luminoso y el crecimiento del cuerpo.

Four specimens of the Caribbean Flashlight about I km wide at the capture site, dropping Fish, Kryptophanaron alfredi Sylvester and off rapidly from a 15 m ledge into several Fowler 1926, were recently collected at San hundred meters depth. The dropoff is Salvador, Bahama [slands. The discovery of this occasionally cut by narrow rock-walled crevices anomalopid at , as well as and sand chaonels. Divers first observed informatiO'n concerning its behavior, juvenile Kryptophanaron below Ihe dropoff at about 20 pigmentation and growth, has prompted this m, and collected small fish using bright reporto Scubapro dive lights which stuoned the fish at The secretive and noctumally active close range. (11 is important to note that behavior of anomalopids has severely limited because of the fish's sensitivity to light , it is the knowledge about this group of imperative that divers avoid turning on their fishes. Kryp tophanaron alfredi was known lights except to stun and capture specimens.) from a single specimen since its discovery in The lights of Kryptophanaron were diffic ult to in 1907 until its rediscovery at Grand differentiate from the ubiquitous Cayman, Cura�ao, and in 1977 bioluminescent plankton (presumably salps, (Rosenblatt and Montgomery, 1976; McCosker, siphonophores, and pyrosomes); however, upon 1977; Colin et al. , [979). Despite the intensive careful examination the fish could be discerned ichthyological surveys of the Bahama [slands by their occasional blinking behavior. AII fishes undertaken by J. Bohlke , C. Chaplin, and seen were alone. The largest individual (63 mm nu�ous other scuba-diving ichthyologists, K. SL) was captured at 40 m depth along the edge ./ alfredi was unknown there, presumably because of a vertical reef channel; the smaller specimens anomalopíds are only encountered as a result of (25.0, 33.0, 45.6 mm SL) were captured at the extraordinary diving conditions. reef dropoff (20-25 m) or along the edge The Bahaman specimens (CAS 45763) were immediately above it. Prior to capture, all fish collected by the author and Jerry Schively, were observed a meter or less aboye the Hugh Downs, and Sylvia Earle at Fernandez bottom, swirnming slowly and occasionally Bay, along the west coast of San Salvador blinking, in the fo od-search behavíor typical of [sland on 20 April 1980 between 2300 and anomalopids. 2400 hrs. The moon was entering the first The coloration of the smallest individual is quarter; however, the late afternoon and night of particular interest. The 25 mm specimen is sky was overcasl with heavy cloud cover and less pigmente d than the slighlly larger occasional lightning flashes. The narrow sand, individuals and adults (compare Figs. [ and 2). coral and rock reef encircling San Salvador is When captured on !he reef, its nearly 98 REVISTA DE BIOLOGIA TROPICAL

I

Fig. 1. Juvenile Kryp tophanaron alfredi, 25.0 mm Fig. 2. Adult Kryptophanaron al/redi, 89 mm SL SL, alive in Steinhart Aquariurn seven days after Note the difference in pigmentation and the capture. Note the unpigmented portions of the fins development of the lateral tinc scales and reflective and body. The light oIgan is partially occluded scalesalong the median Cm bases. through partiaJ ventrolateral rotation and the uplift of the opaque rnembrane.

transparent hind body (particularly Ihe caudal TA8LE 1 peduncle) gave it Ihe appearance of a cardinal I.i� hf OrgDn I.tllXlh (WL) ol Kryptophanaron alfrcd,i exprused os a proportion 01 the StondQTd f.en¡:th (SL). lIead fish . Other transparent areas inelude the Length (111.).ami Orbil I.ength (Of.). Based upon CA S 40798, Grand CaYl1lOn (GC): C4S 45872. PI/erro Rico (PR); ond CAS 45873. segmented dorsal fin and Ihe central portions of Son Sol�odor. BoJlomos (SS) Ihe caudal and pelvic fios. The rellective scale SL(rnrn) LOLlSL LOL/HL LOL/OL Locality band which lies along Ihe dorsal-fin base of adults was limited to two pairs of shiny scales. 25.0 .\84 .447 .885 SS 45.6 .145 .363 .846 SS The lateral-line scales and ventral seu tes were 60.0 .137 .373 .812 CC not noticeably reflective, unlike the condition 68.5 .131 .34\ .857 CC 83.5 .123 .352 .861 PR of adults . The 25 mm specime n lived in an 89.0 .121 .349 .874 PR aquarium for 10 days afler capture, during which Ihe caudal area but not Ihe fins became possible inconsistencies in our melhodology). It darkened much like Iha t of an adulto Its smaU should be noted Ihat the relationship of eye size and translucent properties would indjcate size to light organ lenglh follows a normal that it had recently settled from the plankton pattern of negative allometry in that it is and onto Ihe reef. (It is the smallest specimen obviously advantageous to !his nocturnal fish to of any anomalopid I have observed in museum maximize its eye size Ihroughout life. A similar coUections or found reported in the literature.) comparison was made of the allometric growlh The larval condition and habitus of of the light organ of anolher anomalopid, anomalopids is unknown. It seems most likely Photoblepharon palpebratus; the data indicated that anomalopid larvae are pelagic for a limited a similar, but less significant, trend. duration, in a manner similar to other The discovery of this presumably newly beryciforms. settled, partially pigmented juvenile with large, The relatively large size of the light organ of luminescent organs raises intriguing questions the small specimen was immediately apparent. and suggests furthe r study. In particular, are the The organ is disproportionately large in smaller light organs luminescent when the juvenile specimens (Table 1), a characteristic of obvious Kryptopha1Ulron is in its (presumably) advantage to a smaU, nocturnal ly-active reef planktonic larval state? Further diving fish tha! depends on the light it produces to observations using the methodology described observe its prey (McCosker, 1977). herein, as well as nearshore springtime p1ankton Measurements taken by Colin et al. (I 979, e oHections, should further enlighten the Table 1) from seven Kryptopha1Ulron specimens students of this curious group of luminous (58-105.6 mm SL) demonstrate the same fishes. allometric relationship of light organ length and I sincerely thank Ihe Charline H. Breeden light organ deplh to the standard length (those Foundation for grants in support of my data were not included wilh mine because of ongoing studies on bioluminescence; the lohnson's Wax Fund and Dcean Trust McCosker, J.E. 1977. Flashlight fishes. Sci. Amer. Foundation, for travel assistance to San 236: 106·114. Salvador; Ken Lucas and Al Castro for lhe use of their photographs; and Richard Rosenblatt and Lillian Dempster for their critical reading Rosenblatt, R.H. & W.L. Montgomery. 1976. of this manuscript. Kryptophaneron harveyi, a new anomalopid fish from the eastem tropical Pacific, and the evolution of the Anomalopidae. Capeia, 1976: 510-515. LITERA TURE CITED

Colin, P.L., D.W. Arneson-, & W.F. Smith-Vaniz. 1979. Rediscovery and redescription of the Caribbean Silvester, D.F., & H.W. Fowler, 1926. A new anomalopid fish Kryptophanaron alfred; Silvester and of phosphoresce·nt fish, and Fowler (Pisces: Anomalopidae) . Bull. Mar. Kryptophanaron alfredi. Prac. Acad. Nat. Sci. Sci., 29: 31 2·319. Philad., 78: 245-247.

ERRATA

López, Myrna l.: Los "Roncadores" del género Pomadasys (Haemulopsis) (Pisces: Haemulidae) de la costa Pacífica de Centro América. Rev. Biol. Trop., 29(1): 83-94, 1981.

p.85 En la clave se omitió todo el punto 3.b. Debe leerse: 3.a. Perfil ventral casi recto; altura de la cabeza por el punto medio del ojo 1.8 a 1.9 en la longitud de la cabeza; tercera espina anal defleccionada no llega al extremo posterior de la base de la aleta anal, branquiespinas

11-13...... P. elongatus

3.b. Perfil ventral convexo; altura de la cabeza por el punto medio del ojo 1.6 a 1.7 en la longitud de la cabeza; tercera espina anal defleccionada llega o pasa el extremo posterior de la base de la aleta anal;

branquiespinas 1 Q-13 ...... P. leuciscus.

Sáenz, l.A. Y Ana V. Macaya Lizano : Phyllacora stahlii (Chardon) Stevenson, parásito de Ficus goldmanii: nuevo registro para Costa Rica. Rev. Biol. Trop., 29(2): 295-298, 1981.

pp. 296 Y 297. Las leyendas de las figuras 1 y 2 están invertidas con las de las figuras 3 y 4.