<I>Lampadioteuthis Megaleia</I>
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A NOTE ON THREE SPECIMENS OF THE SQUID LAMPADIOTEUTHIS MEGALEIA BERRY, 1916 (CEPHALOPODA: OEGOPSIDA) FROM THE ATLANTIC OCEAN, WITH A DESCRIPTION OF THE MALEl RICHARD E. YOUNG Institute of Marine Science, University of Miami ABSTRACT The male and larvae of Lampadioteuthis megaleia Berry are described for the first time. The presence of a single penis and a hectocotylus, and the discovery of a rostrum on the pen prompt a re-examination of the characters that have placed this animal as the sole representative of the subfamily Lampadioteuthinae. INTRODUCTION In 1916 S. Stillman Berry described a cephalopod, Lampadioteuthis megaleia, from a lone specimen collected on the beach in the Kcrmadcc Islands in the South Pacific Ocean. For this small animal having an unusual assortment of light organs, he erected a new family, Lampadioteuthidae, primarily on the basis of its rather peculiar gladius, which showed affinities to both the Enoploteuthidae and the Lycoteuthidae. No further information on this new group has appeared in the ensuing half century. In 1962, Voss, in his monograph of the Lycoteuthidae, indicated that the similarities between Lampadioteuthis and the lycoteuthid genera were sufficient to include this animal in the latter group at the subfamily level, thus following Thiele's classification (1934). However he was unable to definitely establish its position within the family without the study of additional material. An examination of the collections of cephalopods from the DANA Expeditions, which are presently on loan to The Marine Laboratory of the University of Miami, has revealed three additional specimens of Lampadio- teuthis megaleia, two of which are larvae. All three specimens were taken from the Atlantic Ocean, thus greatly extending the known range of this species. Berry's original specimen was a female. Therefore, it is fortunate that the largest of the animals described here is a male (Fig. 3). This is particularly important since the lycoteuthid genera are characterized by rather unusual features of the male reproductive system. Since this squid is in an excellent state of preservation (which, unfortunately, was not the lContribution No. 559 from The Marine Laboratory, Institute of Marine Science, University of Miami. Papers from the "Dana" Oceanographical Collections No. 54. This study was supported by grant GB-I090 from the Nalional Science Foundation. 1964] Young: Notes on Lampadioteuthis Megaleia 445 case with the Kermadec specimen), it is now possible to amplify the original description both in the general characters of the species and in the details of the male genitalia. ACKNOWLEDGMENTS The writer thanks the Carlsberg Foundation for the opportunity to examine the DANAmaterial and Dr. Gilbert L. Voss of The Marine Lab- oratory of the University of Miami for his assistance with the manuscript. Lampadioteuthis megaleia Berry, 1916 Figures 1-4 Lampadioteuthis megaleia Berry, 1916: 52.-Voss, 1962: 300. Description.-The mantle is short and muscular, its length being slightly greater than twice its width. The mantle margin projects slightly in the nuchal region but more distinctly so in the areas of the mantle locking apparatus. The outer integument of the mantle extends to the posterior termination of the fins, but the mantle muscle ends a short distance anterior to the apex of the fins. The fins are broad, their width approximately equaling the mantle length, and join in the midline posteriorly where they extend past the apex of the mantle. The gladius (Fig. 4b) is distinct from that of any other known cephalo- pod. Its rachis is long and straight anteriorly, and its thin vane extends laterally, the outer margin of which makes a rather sharp angle just posterior to the midpoint of the pen. At its posterior end, the vane flares slightly and its edges turn under to form a narrow ledge which then follows around the blunt end of the pen. Throughout its length, in the midline of the rachis, a slight thickening occurs which emerges a short distance from the posterior end of the pen as a slender, pointed rostrum. The fact that this rostrum is not a continuation of the posteriormost point of the gladius makes this pen unique among teuthoids. FIGURE 1. Lampadioteuthis megaleia Berry. a, Large sucker from left ten- tacular club.-b, Ventral sucker from base of second right arm.-c, Sucker from middle of second right arm. 446 Bulletin of Marine Science of the Gulf and Caribbean [14(3) The funnel is short, compact and muscular. The funnel groove is well defined laterally but not anteriorly where it merges with the ventral surface of the head; therefore, a foveola is lacking. The funnel organ is of the typical teuthoid form, consisting of a large, inverted V-shaped dorsal pad and two oval ventral pads. The funnel locking apparatus is pointed anteriorly, blunt posteriorly, and contains a simple, straight groove which opposes a straight ridge on the mantle. The head is approximately the same width as the mantle but narrows slightly anteriorly and ventrally. Two pairs of poorly defined nuchal folds are present; the dorsalmost one arises in the mid-lateral point on the back of the head and travels nearly to the nuchal region, while the ventral most is shorter and arises just lateral to the funnel. Near the dorsal border of the ventral nuchal fold lies a small lobe upon which the olfactory papilla is located. The eyes are extremely large, extending almost the entire length and depth of the head. The eye opening is oval and without a marginal sinus, although there is a slight swelling of the tissue at its anterior border. The arms are roughly subequal in length with the exception of the first pair which is much the smallest. The arm formula is 2> 3 > 4 > 1. The suckers are small and biserial; those of the ventral arms are about half the diameter of the rest and arc restricted to a narrower portion of the arm width. A sucker from the middle of the second arm (Fig. Ie) contains eight bluntly pointed teeth on its distal border. The ventral margin of the FIGURE 2. Lampadioteuthis megaleia Berry. Ventral view of larva. 1964] Young: Notes on Lampadioteuthis Megaleia 447 first three pairs of arms contains extremely well developed trabeculate protective membranes, while the membranes on the ventral pair are reduced. The protective membranes on the dorsal borders of the arms are all greatly reduced, being represented primarily by stubby trabeculae. The swimming membrane is well developed on all arms except for the dorsal pair where it forms only a narrOw ridge. The buccal membrane consists of two highly papillated lobes, one extending between the dorsal pair of arms and the other up the third left arm. There is no evidence to indicate that this area was damaged during capture. However, in light of the FIGURE 3. Lampadioteuthis megaleia Berry. Male, ML 31 mm. Ventral view. 448 Bulletin of Marine Science of the Gulf and Caribbean [14(3) fact that Berry's specimen had an eight-lobed membrane, as do the two larval specimens, the unusual nature and asymmetrical position of these lobes must indicate an abnormal condition. The tentacles are robust and taper slightly, being about one and a half times the length of the arms. The tentacular stalks are smooth except for the presence of a few carpal suckers and light organs. The club (Fig. 4c) is small, being between one-fourth to one-fifth the length of the stalk and slightly expanded by the presence of narrow protective membranes. The suckers are in four rather irregular rows on the manus and are set on somewhat elongate stalks. They become progressively smaller on the dactylus and are there arranged into four very regular rows. The distal edge of the largest sucker ring contains eleven small pointed teeth (Fig. la). The carpus contains six scattered suckers on the left stalk and five on the right which are easily distinguished by their narrow and smooth chitinous rings. Knobs on the carpus which would be expected to oppose the suckers could not be found. A narrow swimming membrane runs along the aboral edge of the dactylus. The light organs are large and distinctive (Fig. 3). Each tentacle contains five pearly white organs, the first four being nearly equally spaced while the fifth, lying near the carpus, is somewhat more separated from its fellow. They all protrude slightly from the surface of the stalk except for the peculiar basal organ, which is raised completely off the tentacle by a short pedicel. The light organs of the eyes are perhaps the most easily recognized characteristic feature of this species. Berry (1916, p. 55) has described them as follows: "Subocular photophores large, circular in outline, whitish; four in number on each eye; three, of which the median is somewhat the smaIlest, occupy the usual situs on the ventral periphery; the fourth is larger than any of these, and situated just within the boundary of the pupil, at a point almost exactly behind the centre of the lens." The present specimen differs from this description in that the photophores are brownish in color; the anterior member of the left eye is missing (apparently due to injury), and all the organs are approximately the same size. On either side of the rectum lie two large circular anal photophores with a rather granular appearance and a striking magenta color. At the base of each gill lies a transversely elongate abdominal light organ with a pearly white appearance. Near the end of the mantle, apparently within the median septum and attached to both the inner surface of the mantle and the visceral mass, is located a single oval postero-abdominal photophore with a pearly white sheen.