ALBERT

Description: Variations in the distribution and abundance of coastal cephalopods in the Cabo Frio (Brazil) region were studied from 71 trawl samples obtained between November 1986 and October 1988. Species abundance was compared over the depths sampled and their relationship with hydrological features investigated. Best catches were markedly associated with upwelling of nutrient-rich water (South Atlantic Central Water) during the spring-summer period, at depths from 45 to 60 m. Two species, Loligo sanpaulensis and Eledone massyae, account for most of this increase. Variations in abundance of these species are related to recruitment and periods of high productivity on the feeding grounds. Benthic octopods such as Octopus tehuelchus, O. vulgaris and Eledone gaucha occurred in small numbers at 60 m. Species broadly distributed in the western Atlantic, such as Semirossia tenera and Loligo plei, were also present.

Description: Part of the spawning area of the squid, Loligo vulgaris reynaudii, was investigated over a 5-week period using a combination of hydroacoustic techniques, SCUBA dive transects and observations. Egg mass concentrations were identified by a Furuno FCY-663 echosounder, and these were positively confirmed by SCUBA diving. It was found that egg strands were concentrated into distinct, clumped spawning beds which were non-randomly distributed in the study area. Bottom substrata favored by spawning squid appeared to be sandy areas or low profile rocky reefs. The average number of eggs per strand was 148 (±37). This study examines different techniques to estimate numbers of squid eggs in the wild, which may have wider application. Two statistical techniques were used in an exploratory data analysis to estimate the total number of eggs present in the study area, using both random and non-random transect methods. A non-random technique of estimation on clearly defined egg bed areas was found to be the most appropriate, although egg number estimates to date are considered preliminary.

Description: Records of 158 observations of cephalopods from submersibles, primarily the Johnson Sea-Link, have been compiled through collaboration with several investigators. These observations include 118 videotape sequences, 58 collected specimens, and numerous shipboard photographs of live animals. At least 33 species have been observed to date; a few species have been observed repeatedly and could be good subjects for directed studies. The methods developed for in situ observation and subsequent collection of specimens with little or no damage allow descriptions of behavior, morphology, physiology, and distribution that are not possible with other methods of collecting.

Description: Eleven species of paralarvae belonging to the Chiroteuthidae and related families are described from Hawaiian waters. The doratopsis stage is shown to be a diagnostic feature of the family Chiroteuthidae. This family, as now defined, includes the genera Chiroteuthis, Asperoteuthis, Grimalditeuthis and Planktoteuthis. Doratopsis sagitta, Valbyteuthis, Tankaia, Echinoteuthis and Enoptroteuthis spinicauda are placed as junior synonyms of Grimalditeuthis bonplandi, Planktoteuthis, Chiroteuthis, Mastigoteuthis and Lepidoteuthis grimaldii respectively. An unknown type of paralarva referred to as “big-fin” is described. Members of the “chiroteuthid lineage” which apparently includes the Chiroteuthidae, Mastigoteuthidae, Joubiniteuthidae, Batoteuthidae, Promachoteuthidae and “big-fin” may all have secondarily derived tentacular clubs.

Description: In the coastal waters between Cabo Frio, Rio de Janeiro State (Lat. 23°S) and Chui, Rio Grande do Sui State (Lat. 34°S), more than 30 species of cephalopods occur in the different marine environments. Temperate benthic octopuses of low fecundity, bearing large eggs, are restricted to the cold bottom waters of the outer shelf and the slope, in contrast to species of tropical origin, which occupy the more diverse shallow water habitats, principally along the Rio de Janeiro coast. Cosmopolitan warm-water octupuses with high fecundity, like Scaeurgus unicirrhus and Octopus vulgaris, are found along the entire area because the transport of pelagic juveniles is favored by the warm, southward flowing superficial Brazil Current. All three families of epipelagic octopuses are represented. The neritic squid fauna includes only five myopsid squids, four of them of tropical origin. At the upper slope Illex argentinus is dominant and several mesopelagic and bathipelagic oegopsids, widely distributed in tropical and temperate Atlantic Ocean waters, also occur. The absence of endemic species indicates the transitional character of the fauna between the Caribbean and the Patagonian regions.

Description: Based on sequential growth stages of Moroteuthis robusta, M. japonica and M. pacifica are synonymous with M. robusta, and smaller stages are bridged to the Onykia “carribaea” species complex. Within the family Onychoteuthidae, the genus Onykia has in common with the genus Moroteuthis the absence of both visceral photophores and dorsal nuchal folds. Young Moroteuthis have a smooth mantle surface with a distinct iridescence, a small number of marginal suckers on the tentacular club and an indistinct cartilageous cap on the endocone. While, large Onykia develop rhomboidal fins, an inverted Y-shaped cartilageous ridge in the funnel groove, and a reduced number of marginal suckers on the club, all of which characterize Moroteuthis. Close examination of a series of O. “carribaea” specimens reveals that the species is not monospecific, but contains more than one species. It is thus suggested that the genus Onykia, therefore, appears to represent juvenile stages of the genus Moroteuthis.

Description: Cephalopods are a common but not abundant element of the micronekton of the eastern Gulf of Mexico, an area hydrographically and biologically similar to low latitude oligotrophic oceans throughout the world. Forty seven species were identified from Tucker trawl collections in the vicinity of 27°N, 86°W, with seven new records for the Gulf. All species have been recorded from the Atlantic and 69% are pan-oceanic at low latitudes. The Teuthoidea were the largest fraction of the catch, particularly species of the families Enoploteuthidae and Cranchiidae. All but three species occurred in the epipelagic zone at night and diel vertical migration is suggested for many of the population. Closing trawl data indicate that most of the cephalopod population occurs shallower than 200 m at night and centers at 100 to 400 m during the day. Populations of several of the abundant, smaller species were greatest in July but this could not be linked, on the basis of size measurements, to recruitment of juveniles to the population. Diet analysis indicates that micronektonic cephalopods are crustacean feeders as juveniles, but rely more on fish as they mature (〉4 cm mantle length). Some cannibalism is apparent. Cranchiids contained relatively little food which might result from a relatively inactive life strategy. The latter is suggested by rather flaccid musculature in comparison to other teuthoids. The copepod genus Pleuromamma is highly selected for by a number of species, perhaps a function of the strong bioluminescent signal produced by members of this genus. Cluster analysis revealed several feeding guilds among the abundant species, though intracluster diets usually exhibited strong overlap. Given the relatively low abundance levels of cephalopods (50–70·103km−2; 0–1,000 m), trophic competition may stem primarily from more abundant (〉10×) micronektonic groups such as midwater fishes and shrimps than from other cephalopods.

Description: Samples of Loligo gahi (D'Orbigny) were collected from commercial fishing vessels in the Falkland Islands Interim Conservation and Management Zone (FICZ) between March and October 1987, and from the R/V Wieczno during a survey in August 1988. Samples were divided according to the two fishing seasons (February to July; August to October) and the samples from the scientific survey were pooled with those of the second commercial fishing season. L. gahi were aged using putative daily growth increments within the statoliths. There was indirect evidence that growth increments in the statolith were laid down at the rate of one per day. The maximum life span of the males was a little over 1 year and was approximately 1 year in females. Back-calculation ofthe month of hatching reveals the presence of two spawning groups within the FICZ population which give rise to the two fishing seasons. Growth rates were calculated for both sexes from both seasons. There was considerable individual variation in growth rate in squid from both seasons and there was more scatter in the data from first season samples taken from the commercial fishery alone. Log-linear growth models give the best fit to the data combining the fishery and scientific survey samples from the second season. Very low or apparent negative growth exhibited by squid sampled during the first season may be due to bias because the commercial fishery samples a narrow depth range. Migration of schools of squid of similar size through the narrow depth range in which the fishery operates probably yields samples that are size selected. Care should be taken in modelling squid growth where migratory effects may bias the data.

Description: Geographical variation in the morphological characters of Australian Rossiinae were examined using principal component analysis (PCA), multivariate analysis of variance (MANOVA), discriminant function analysis (DFA), analysis of variance (ANOVA) and latitudinal and longitudinal regression analyses. The results show that morphological differences occur between populations of Rossia from the North West Shelf (W.A.) and populations from eastern and southern Australia. Evidence from these analyses suggest that these two populations are genetically distinct, the North West Shelf specimens belonging to a possible new species, described as R. sp. 1, the eastern and southern Australian specimens identified as R. australis Berry, 1918 and redescribed on the basis of new material. That all the latter specimens belong to a single species is further supported by electrophoretic evidence. A new species of Neorossia, N. leptodons, is identified and described, differing from the only described representative of this genus, N. caroli (Joubin, 1902), in the shape of the radular teeth. The two species were also shown to differ using multivariate statistical techniques. N. caroli is redescribed from the holotype and additional material. In addition, specimens of Neorossia from southeastern Australia are compared electrophoretically with R. australis. It was found that members of these two genera differed for 66% of loci.

Description: The holotype of Octopus schultzei (Hoyle, 1910) was examined, to verify its taxonomic status. The holotype, a male and the only specimen known, possesses unusual characters not referred to in the original description nor in subsequent reports. Most striking are the arm tips, all of which, except the hectocotylus (right third arm), have a mass of long, closely packed finger-like processes instead of suckers. The hectocotylized portion of right arm III is very small, uniform and spongy in structure; the end organ lacks a longitudinal depression and cross-striations; a calamus is absent. These and other characters confirm the specific validity of O. schultzei and readily distinguish it from all other known species of Octopus. The systematic significance of these and other unusual characters supports the establishment of a new genus, Aphrodoctopus.

Description: Cephalopods, including octopus, cuttlefish, and squid, are a major component in the marine biomass. Due to high behavioral diversity among species, uncertainty exists concerning the general applicability of sampling and capture techniques. This factor impacts on understanding of the overall abundance and status of stocks. In addition to accelerated exploitation of cephalopods by international fisheries countries, cephalopods represent a major prey component in the diets of other marine species. In the Southern Ocean alone, it is estimated that the consumption of cephalopods by seabirds, whales and seals may reach 34 million tons annually. On a worldwide basis, the total natural predation on cephalopods probably exceeds 100 million tons, more than the total annual harvest of aquatic species by humans. Scientists and fisheries managers are not able to accurately measure cephalopod stocks under direct exploitation. Yet the relatively few species being exploited comprise only a fraction of available worldwide resources. Some of the traditional capture techniques are discussed with an indication of their effectiveness; possible options and access to new or latent methods also are noted.

Description: Professor Gilbert L. Voss served the leading role in American cephalopod research for nearly 40 years. He drew attention to the importance of cephalopods in marine ecosystems and as fisheries resources. Through his research and that of his students he significantly advanced the knowledge of cephalopod systematics, distribution and biology. An insight into Gil Voss' ideas and attitudes concerning cephalopod research and teaching is given. Voss's broad interests are indicated in his bibliography of over 210 diverse published items, including 73 book reviews, 16 editorials, and 124 research papers on cephalopods, fishes, crustaceans, botany, zoogeography, history of oceanography, anthropology, fisheries, and marine and deepsea biology. He authored or co-authored descriptions of two new families or subfamilies, 6 new genera and more than 65 new species or subspecies.

Description: The diet of Opisthoteuthis agassizi and O. vossi in the southeast Atlantic was studied from 171 and 121 individuals respectively. Small epibenthic and suprabenthic crustaceans and polychaetes are the most frequent prey items in both species, suggesting that they feed on suprabenthic and epibenthic material. Diel analysis of feeding by O. agassizi at 490 m and O. vossi at 836 m depth demonstrated a pattern of continuous feeding. Relationships of total body length and beak measurements to total weight were also studied. The ultrastructure of sucker and cirri are described for both species and their relationship with prey detection mechanisms is discussed.

Description: A new species of octopod, Octopus magnificus, is described based on a total of 131 specimens from the southeastern Atlantic. The species has been collected from 26°03′S, 13°43′E to 34°29′S, 25°36′E between 2–560 m of depth, mainly on fine sandy bottom. The species is characterized by its large overall size, long ligula, the anatomy of the male reproductive tract, the shape of the funnel organ, skin loose and elongate folds present in live animals. O. magnificus is compared to three large octopuses, namely O. dofleini, O. maorum and Enteroctopus megalocyathus.

Description: Inadequate identification of octopus age classes has severely limited field studies of their biology. Four predictions are made to differentiate males at the plateau of growth that precedes senescence, i.e., mature males, from immature males. Compared to immature males, mature males are predicted to be 1) more mobile because their reproductive fitness depends on the number of receptive females they encounter; 2) more often injured, due either to increased mobility or decreased regeneration capacity; 3) more attractive as mates due to their maturity; and 4) mature males, overall, are predicted to be larger due to their advanced age. An intertidal population of Octopus digueti, sampled for 1 year, provided data to test the hypothesis that males with a few conspicuously enlarged suckers represent a mature age class as characterized above. As a group, males of O. digueti with enlarged suckers met these expectations; therefore, the presence of enlarged suckers is concluded to accurately indicate male maturity. I suggest enlarged suckers act as chemoreceptors of chemical cues released by receptive females and thus may contribute directly to male fitness.

Description: Starvation resulting from failure to feed successfully after absorption of the yolk reserves has been proposed to be a major source of pre-recruitment mortality in squids. To test this hypothesis, methods must be developed to determine whether paralarvae have fed successfully at sea. When paralarvae are stained with Alcian Blue and then cleared with trypsin, the entire digestive tract can be examined intact for the presence of food. This method was used for Abralia trigonura and Sthenoteuthis oualaniensis paralarvae from Hawaiian waters. Approximately 9% of the former and 16% of the latter contained recognizable food material, mostly crustacean fragments. Food was found in the stomach, caecum, and intestine. The smallest specimen of A. trigonura with recognizable food in its digestive tract was 2.2 mm dorsal mantle length (DML), while for S. oualaniensis the smallest was 5.2 mm DML. The method is also useful for visualizing the ontogeny of the digestive-tract organs, beaks and radula, and other organs such as statocysts and eyes.

Description: Two cruises in the western North Atlantic collected 38 trawl samples between the Bahamas and New England. Ofthe 22 cirrate octopods taken in these samples, 17 came from the area north of the Bahamas. Pooled catch rate (specimens per hour of bottom trawling time) was significantly higher north of the Bahamas than in any other area sampled. Although the taxonomy of these gelatinous benthopelagic cephalopods is not yet settled, morphological characters from these specimens indicate that this aggregation includes at least four species. Only one species (Cirrothauma murrayi) was widely distributed in these samples.

Description: Teuthowenia is comprised of three discrete, closely related, allopatric species. Synonymies, definitions, diagnoses and keys to all developmental stages are presented, along with a review of the complex history of the genus and detailed illustrations. The discrete, ecologically distinct, distributional patterns of the three species reflect the influence of a number of biological and physical factors. T. megalops (Prosch) is confined to the highly productive Atlantic subarctic and the highly productive areas of the North Atlantic temperate region. T. maculata (Leach) is restricted to the area of year-round, high productivity in the eastern tropical Atlantic. T. pellucida (Chun) is distributed circumglobally in the mixed and fringing waters of the Southern Subtropical Convergence. The species display similar patterns of ontogenetic descent from near-surface waters to midwater depths of about 1,000 m to in excess of 2,500 m where the animals mature, mate and spawn. Teuthowenia species have differentiated physiologically and developmentally as well as morphologically. Variations in the maturity-related morphological features among the species suggest differences in behavioral patterns for courtship and copulation. The genus displays a high rate of evolution in male and female secondary sexual characters. The relationships of Teuthowenia with Egea and Megalocranchia, which together comprise the monophyletic Megalocranchia group, and with the other taoniin genera are discussed.