Assessment of genetic diversity in Calamus thwaitesii BECC. (Arecaceae) using RAPD markers

Calamus thwaitesii Becc. is a potentially useful rattan found in the Western Ghats of India and Sri Lanka. The wild stock of this rattan species is greatly diminished due to overexploitation for the furniture industry and increasingly rare. Genetic diversity was estimated in 80 samples representing eight populations from the Western Ghats and Sri Lanka using Random Amplified Polymorphic DNA (RAPD) markers. RAPDs generated a total of 120 markers with 10 decamer primers, of which 85% were found to be polymorphic. The percentage of polymorphic loci varied from 40.00 to 60.83 and genetic distance between populations ranged from 0.0332 to 0.2777. Among the analysed populations, Goa was found to be genetically superior followed by Achenkovil, Sinharaja and Talakkaveri. Majority of the genetic diversity was distributed within populations (70.79%) and only (29.21%) among populations. Genetic relationships estimated by the unweighted pair-group method with arithmetic averaging (UPGMA) cluster analysis and principal co-ordinate analysis failed to separate Indian and Sri Lankan populations geographically into two distinct groups.     

Isolation and characterization of tri‐ and tetranucleotide microsatellite loci in the Asian elephant,Elephas maximus

Asian elephants (Elephas maximus) are an endangered species. Their future survival depends on intensive conservation and management, based on in‐depth knowledge of particular populations. Molecular genetic methods, especially microsatellite analysis through noninvasive sampling, provides an effective means of obtaining such information. The use of tri‐ and tetranucleotide microsatellite markers is advantageous in noninvasive sampling through dung analysis. Here we describe the isolation and characterization of five tri‐ and tetranucleotide markers in the Asian elephant. All five loci were found to be polymorphic in a sample of 20 Asian elephants from Sri Lanka.     

Phylogenetic relationships and molecular evolution in uropeltid snakes (Serpentes: Uropeltidae): allozymes and albumin immunology

Multilocus electrophoretic methods and microcomplement fixation comparisons of serum albumin are used to assess phylogenetic relationships among species of uropeltid snakes, to infer aspects of their population biology and biogeography, and to evaluate their relationships to other primitive snakes (Henophidia). There is very good agreement between phylogenetic inferences derived from the electrophoretic data and those derived from the albumin immunological data. Protein variation detected by electrophoresis is relatively high among 17 operational taxonomic units (OTUs) examined. The mean number of alleles per locus (5.1 across all OTUs), levels of polymorphism (25% of loci), and heterozygosity (4–6%), are typical of, or greater than, values reported for other snakes. Species of uropeltids are genetically highly differentiated, as measured by genetic distances (lowest interspecific Nei's unbiased genetic distances, 0.22-0.27 among several Sri Lankan species; 2.3 between Teretrurus of India and other uropeltines). The phylogenetic tree most consistent with both the immunological and electrophoretic data shows uropeltines from Sri Lanka to be monophyletic, but the Indian species are paraphyletic with respect to those from Sri Lanka. Rhinophis travancoricus of India is inferred to be the sister taxon to the Sri Lankan radiation. As the genera are presently understood, neither Rhinophis nor Uropeltis appears to be monophyletic. A biogeographic scenario derived from the phylogenetic hypothesis suggests an early diversification of uropeltids in India, followed by a single invasion into the lowlands of Sri Lanka. Subsequent evolution on Sri Lanka resulted in occupation of montane biotopes. Cylindrophis is the sister group to uropeltines and is considered a member of the Uropeltidae. The immunological data indicate no phylogenetic association between uropeltids and other ‘anilioid’ taxa, specifically Anilius, Loxocemus or Xenopeltis, although we cannot rule out a very remote relationship. We specifically reject the hypothesis that uropeltines and scolecophidians form a clade relative to henophidians. High levels of genetic variation and a trend toward negative F_IS values for polymorphic loci in three populations suggest generally large effective population sizes and outbreeding in these species. The niche-width variation hypothesis for allozyme loci is not supported by the uropeltid data. In comparison to other vertebrates, the relationship between Nei's genetic distance and albumin immunological distance in uropeltids suggests either conservative albumin evolution or strong differentiation at electrophoretic loci.     

PHYLOGEOGRAPHY OF THE ASIAN ELEPHANT (ELEPHAS MAXIMUS) BASED ON MITOCHONDRIAL DNA

Abstract Populations of the Asian elephant (Elephas maximus) have been reduced in size and become highly fragmented during the past 3000 to 4000 years. Historical records reveal elephant dispersal by humans via trade and war. How have these anthropogenic impacts affected genetic variation and structure of Asian elephant populations? We sequenced mitochondrial DNA (mtDNA) to assay genetic variation and phylogeography across much of the Asian elephant's range. Initially we compare cytochrome b sequences (cyt b) between nine Asian and five African elephants and use the fossil‐based age of their separation (～5 million years ago) to obtain a rate of about 0.013 (95% CI = 0.011–0.018) corrected sequence divergence per million years. We also assess variation in part of the mtDNA control region (CR) and adjacent tRNA genes in 57 Asian elephants from seven countries (Sri Lanka, India, Nepal, Myanmar, Thailand, Malaysia, and Indonesia). Asian elephants have typical levels of mtDNA variation, and coalescence analyses suggest their populations were growing in the late Pleistocene. Reconstructed phylogenies reveal two major clades (A and B) differing on average by HKY85/Γ‐corrected distances of 0.020 for cyt b and 0.050 for the CR segment (corresponding to a coalescence time based on our cyt b rate of ～1.2 million years). Individuals of both major clades exist in all locations but Indonesia and Malaysia. Most elephants from Malaysia and all from Indonesia are in well‐supported, basal clades within clade A, thus supporting their status as evolutionarily significant units (ESUs). The proportion of clade A individuals decreases to the north, which could result from retention and subsequent loss of ancient lineages in long‐term stable populations or, perhaps more likely, via recent mixing of two expanding populations that were isolated in the mid‐Pleistocene. The distribution of clade A individuals appears to have been impacted by human trade in elephants among Myanmar, Sri Lanka, and India, and the subspecies and ESU statuses of Sri Lankan elephants are not supported by molecular data.     

Molecular diversity and genetic relationships among Sri Lankan pomegranate Punica granatum landraces assessed with inter simple sequence repeat (ISSR) regions

Pomegranate Punica granatum was first introduced to Sri Lanka, possibly through ancient trade routes, thousands of years ago. However, there is no information about the diversity of the pomegranate germplasm in the country, which is important both for breeding new varieties and for conservation efforts. We used inter‐simple sequence repeat (ISSR) regions to investigate the genetic diversity and population structure of pomegranate on the island of Sri Lanka. Hundred and twenty accessions representing seven populations from all pomegranate growing regions of the country were analyzed using 20 ISSR primers. A total of 107 loci were amplified with an average polymorphism information content of 0.3. While the average inter‐population genetic distance was 0.141, it was 0.149 between populations, indicating moderate genetic diversity both within and among populations. Analysis of molecular variance and Nei's genetic diversity revealed higher genetic variation within populations than among populations, and low genetic differentiation (G_ST) in pair‐wise comparison of populations also suggested limited population differentiation. A considerable level of among‐population gene flow (Nm) was indicated, irrespective of geographical structure and distances. The results of cluster analysis was also in agreement with above analysis and suggest human mediated gene flow and migration patterns. Cluster analysis revealed two main population clusters with several sub‐clusters. While these clusters did not show any correlation with geography, all red peeled accessions clustered into a small sub‐cluster. The results indicate that analysis of ISSR variability is sufficiently informative and powerful to assess the genetic diversity of P. granatum landraces in Sri Lanka.     

Genetic variation in Sri Lankan leopards

Electrophoretic variation of 50 gene-enzyme systems was typed in a population of 33 captive leopards (Panthera pardus) from the island of Sri Lanka. The captive leopard population was composed of several lineages: (1) wild-caught leopards of the island subspecies (P. p. kotiya), (2) captive-born animals of the same subspecies, (3) a melanistic lineage whose founders were obtained from Malaysia (P. p. delacouri), and (4) leopards of known mixed lineage and unknown status. Two loci, APRT and PGD, were polymorphic in all samples, whereas 48 loci were invariant. Percent polymorphism (P) and percent average heterozygosity (H) were calculated as 4% and 1.4%, respectively, for the wild-caught leopards; 4% and 1.2% for the captive-born kotiya leopards; and 4% and 2.0% for the melanistic lineage. The overall results revealed a detectable decrease in genetic variability compared with a previous study of captive leopards from mainland origins. The mainland leopards had three additional polymorphic loci, ADA, ESI, and HBB. Reexamination of the TF locus using a revised protocol resolved a new allele in the sample of mainland leopards but not in the Sri Lankan sample. With this new polymorphism, recalculated P and H values for the mainland sample are 10% and 3.1%, respectively. No significant differences in polymorphic loci were observed between the leopard subspecies examined.     

Phylogenetic affinities of the Iraqi populations of Saw-scaled vipers of the genus Echis (Serpentes: Viperidae), revealed by sequences of mtDNA genes

The Saw-scaled vipers of the species Echis carinatus range from Sri Lanka and India westwards to Iraq, including the eastern Arabian Peninsula. We collected the species in southern Iraq and compared two mtDNA genes (16S and Cyt b) with other populations of this species and with other species of the genus. Analyses of both Maximum Likelihood and Bayesian Inference confirmed E. carinatus as a monophyletic species. The samples from Iraq cluster with populations of the species from Pakistan and UAE. Populations from India, however, are situated in a separate phylogenetic lineage. This can be explained by the geographic barriers between western (Iraq, Pakistan and UAE) and eastern (India) populations of the species. Soleyman Mountain in southern Pakistan is the main barrier between them and its role is reflected in the genetic distance between populations.     

Genetic variation in Ecballium elaterium (Cucurbitaceae): Breeding system and geographic distribution

Dioecy, the separation of sexes, has arisen independently many times in the course of angiosperm evolution. Avoidance of inbreeding is clearly involved in the evolution of dioecy, and as a consequence we predict that dioecious populations should maintain higher levels of genetic variation than closely related nondioecious populations. We tested that prediction by comparing allozymic variation in two closely related taxa, the monoecious and dioecious subspecies of the Mediterranean cucurbit, Ecballium elaterium. Thirteen polymorphic loci were screened for seeds sampled from 10 monoecious and 13 dioecious populations spanning the geographic ranges of the subspecies in Spain. The dioecious subspecies showed strikingly greater allelic diversity and heterozygosity than the monoecious subspecies. A hierarchical F-statistic analysis clearly demonstrated considerable genetic variation within populations for the dioecious populations, whereas for the monoecious populations almost all genetic variation resulted from differences among populations. The general pattern of homozygosity within monoecious populations suggests that they are highly inbred. In order to assess historical influences on current patterns of genetic variation, we conducted a genetic-distance analysis. The observed relationship between genetic distance and geographic distance between populations supports the hypothesis that the subspecies' current allopatric distributions on the Iberian Peninsula are the result of separate waves of colonization from the north (monoecious) and south (dioecious).     

GENETIC DIFFERENTIATION IN THE FLORIDA SUBSPECIES OF HELIANTHUS DEBILIS (ASTERACEAE)

Techniques of horizontal starch gel electrophoresis were employed to estimate levels of genetic variation within and genetic differentiation among populations of the three Florida subspecies of Helianthus debilis. The subspecies are H. d. debilis, H. d. vestitus, and H. d. tardiflorus. These taxa are very similar with respect to levels of genetic variability. The average values across all populations for proportion of polymorphic loci (25.5%) and number of alleles per polymorphic locus (2.35) are comparable to those found in other outcrossing plants. The average frequency of heterozygotes per locus (0.05) is lower than that found in other outcrossers. Local populations within each subspecies are genetically very similar. The average genetic distance between local populations is D = 0.010 ± 0.001. Subspecies vestitus and subspecies tardiflorus are also genetically very similar (D = 0.015 ± 0.001). However, subspecies debilis is differentiated from both subspecies vestitus (D = 0.121 ± 0.006) and subspecies tardiflorus (D = 0.103 ± 0.005). This genetic differentiation parallels morphological differentiation. The average genetic distance among all three subspecies is D = 0.080 ± 0.003. A moderate amount of genetic differentiation accompanies the process of subspeciation in Helianthus debilis.     

Genetic variability within and between the troops of toque macaque,Macaca sinica,in Sri Lanka

Genetic variability within and between the troops of toque macaque in Sri Lanka was studied from a population genetical perspective. Studies were made using electrophoretical blood protein variations as markers in order to clarify the genetic characteristics of the population of this species. A total of 256 samples from 20 troops which were collected in the field in 1981 to 1982 and 1983 to 1984 were examined for 32 blood protein loci. Eleven loci, that is, Tf, Alb, TBPA, Hb-α, PHI, PGM-II, CA-I, IDH, AK, ADA, and Ch-E showed the polymorphism in one or more troops. Of these 11 loci, 7 loci, that is, Tf, TBPA, Hb-α, PHI, PGM-II, CA-I, and IDH were highly polymorphic in most troops. The genetic variability within troops were quantified as H=0.0782 in average and this value was on higher level than other primates and comparable with that of continental macaques,Macaca fascicularis, in Thailand. The genetic differentiation between troops was quantified byG _ST andF _ST and these values were relatively smaller than those of other insular macaques.     

The origin of Indian Star tortoises (Geochelone elegans) based on nuclear and mitochondrial DNA analysis: A story of rescue and repatriation

The Indian Star tortoise (Geochelone elegans) belongs to the family Testunidae and is distributed in southwest India and Sri Lanka. In addition to facing loss of its natural habitat, the species is also illegally traded as food and as an exotic pet internationally. Here we report DNA-based analyses for identification and repatriation of these tortoises into their natural habitat. We have attempted to establish the geographical origin of these tortoises rescued from smugglers, by comparing the microsatellite and mitochondrial markers of rescued animals with animals of known provenance. Star tortoises exhibited strong genetic structure in India. The populations from western India were genetically distinct at microsatellite and mitochondrial loci from southern populations. The rescued individuals had similar multilocus genotypes and mitochondrial DNA haplotypes as the reference individuals from south India. However, the precise geographic origin of many of the rescued samples remains unresolved, because we could not assign them to southern populations and the Neighbor-Joining cluster analysis indicated that some of rescued tortoises formed distinct clusters. These data strongly suggest that the rescued group of tortoises is composed of a mix of individuals from differentiated source populations that are probably located in southern India and possibly Sri Lanka. Our study provides valuable information based on molecular markers for the assessment of genetic diversity in Indian Star tortoises.     

Congruence between environmental parameters, morphology and genetic structure in Australia’s most widely distributed eucalypt, Eucalyptus camaldulensis

Eucalyptus camaldulensis is one of the most widely utilised eucalypts. It is also the only eucalypt that occurs across the Australian continent, playing a key ecological role as fauna habitat and in riverbank stabilisation. Despite its ecological and economic importance, uncertainty remains regarding the delineation of genetic and morphological variants. Nine hundred and ninety trees from 97 populations, representing the species’ geographic range were genotyped using 15 microsatellite loci and patterns of diversity compared with restriction fragment length polymorphisms in 29 of these populations. Both markers showed that despite having a riverine distribution, downstream seed dispersal has had less influence than geographic distance on dispersal patterns. Spatial patterns in the distribution of microsatellite genotypes were compared with environmental parameters and boundaries defined by river systems, drainage basins and proposed subspecies. Significant genetic differences among populations within river systems indicated that rivers should not be treated as a single genetic entity in conservation or breeding programmes. Strong geographic trends were evident with 40% of variation in genetic diversity explained by latitude and moisture index. Isolation by distance and significant correlations between genetic distance and environmental parameters for most loci suggest historical factors have had more influence than selection on current patterns of distribution of genetic diversity. Geographic structuring of molecular variation, together with congruence between genetic and morphological variation indicate that E. camaldulensis should be treated as a number of subspecies rather than a single variable taxon. High levels of genetic diversity and geographic trends in the distribution of variation provide a firm basis for further exploration of the species’ genetic resources.     

Genetic markers distinguishing between the two subspecies of the rosy bitterling,Rhodeus ocellatus (Cyprinidae)

Eleven populations of the rosy bitterling,Rhodeus ocellatus, from different localities in Japan, were genetically compared at 16 protein-coding loci using starch-gel electrophoresis. Two loci,Ldh-2 andPgdh, were demonstrated as diagnostic markers for the identification of two subspecies;R. ocellatus kurumeus, which is native to Japan, andR. ocellatus ocellatus, which was introduced from China. The two subspecies were distinguished by the complete substitution of different alleles between them. Population ofR. ocellatus kurumeus occurring in Yao City, Osaka, and in Kanzaki, Saga Prefecture were genetically closely related to each other (genetic distance: D=0.056) but distantly so toR. ocellatus ocellatus from Saitama Prefecture (D=0.202 or 0.265). Electrophoretic analyses also elucidated the existence of hybrid populations of the two subspecies. The populations ofR. ocellatus kurumeus in Yao City had lower genetic variability and a lower incidence of white coloration on the ventral fins than populations of the same in Saga Prefecture. The present study strongly implies that the introduction of the foreign freshwater fishes with subspecific differentiation, into the original range of indigenous subspecies, should be averted not to bring the genetic pollution.     

Genetic differentiation of the Fejervarya limnocharis complex from Bangladesh and other Asian countries elucidated by allozyme analyses

The present study was conducted to elucidate the genetic divergence and the phylogenetic relationships in the F. limnocharis complex from Bangladesh and other Asian countries such as Sri Lanka, Thailand, Malaysia, Taiwan and Japan by allozyme analyses. We used a total of 95 frogs of the F. limnocharis complex from these countries and F. cancrivora from the Philippines as an outgroup. Based on body size, the F. limnocharis complex from Bangladesh was divided into three distinct groups: large, medium and small types. Allozyme analyses were carried out with 28 loci encoding 20 enzymes and two blood proteins by horizontal starch-gel electrophoresis. When genetic distance was calculated, distinct divergence was found among the three types: mean genetic distance was 0.782 between the small and medium types, 1.458 between the large and medium types, and 1.520 between the large and small types. Phylogenetic trees based on genetic distance showed that all populations of Bangladesh small type strongly formed a cluster and were found to be most closely related to the Sri Lanka population; that all populations of Bangladesh large type formed a very strong cluster and were grouped with several populations from Thailand, Malaysia, Japan, and Taiwan; and that the medium type was segregated from all other groups. This may imply that each of the three types is a different species, and that the medium type is possibly an undescribed taxon.     

Cryptic species,taxonomic inflation,or a bit of both? New species phenomenon in Sri Lanka as suggested by a phylogeny of dwarf geckos (Reptilia,Squamata, Gekkonidae,Cnemaspis)

We evaluated the status of 16 of 22 recognized Sri Lankan Cnemaspis Strauch species, and flagged overlooked diversity with two mitochondrial (cyt b & ND2) and two nuclear markers (RAG1 & PDC) totalling 2829 base pairs. A fossil-calibrated timetree and sampling of other South Asian Cnemaspis provide insights into the diversification of the genus in peninsular India and Sri Lanka. Phylogenetic analyses consistently inferred two broad clades within South Asian Cnemaspis, with Sri Lankan species in two clades, which we call the podihuna and kandiana clades. Each Sri Lankan clade as a whole is sister to Indian taxa and nested within Indian lineages. Cnemaspis modigliani Das from Indonesia is a member of the kandiana clade. This suggests a minimum of two dispersal events between India and Sri Lanka and one between Sri Lanka/India and South-east Asia. South Asian Cnemaspis date back to at least the Eocene, in Sri Lanka to the early Miocene, with late Miocene diversification in the kandiana clade. All but one of the named species we sampled is likely to be valid, and 10 divergent unnamed lineages may warrant specific recognition. A resolution of Sri Lankan Cnemaspis taxonomy will require thorough sampling and the use of both morphological and molecular data.     

RAPID MORPHOLOGICAL CHANGE IN CHANNEL ISLAND DEER MICE

Deer mice, Peromyscus maniculatus, collected over 90 years from three California Channel Islands, were examined for evidence of morphological change. Rapid morphological change has occurred in the endemic subspecies from Santa Barbara (P. m. elusus), Anacapa (P. m. anacapae), and Santa Cruz Island (P. m. santacruzae). Data were divided into two temporal classes, 1897–1941 and 1955–1988. Of the 16 morphological characters measured, between five and 10 measures changed significantly (P ? 0.05) with temporal class in each subspecies, and multivariate test statistics were significant (P ? 0.05) for all three subspecies. For each subspecies, depth of braincase, total length, tail length, and hind foot length became smaller over time, except depth of braincase, which became larger in P. m. elusus. The rates of change dramatically exceed those estimated from paleontological records and are even higher than those reported in some experimental selection studies. Temporal change in two characters exceeds differentiation between subspecies. Although changing, each subspecies remained well differentiated, and incorporation of temporal change allowed correct classification of most specimens. Unlike nearly all previous reports of rapid evolution, the changes in these populations were not associated with a founder events or recent introductions. This study demonstrates that rapid phenotypic change can occur in long-established natural populations and temporal stability of morphological characters in such populations, even over short evolutionary time periods, cannot be assumed.     

Genetic Divergence and Similarity of Introduced Populations of European Beaver (Castor fiber L., 1758) from Kirov and Novosibirsk Oblasts of Russia

Potential factors were analyzed that affected the formation of gene pools of two introduced beaver populations founded in the 1940s–1950s by releasing beavers from Voronezh oblast and Belarus into rivers of the Kirov and Novosibirsk oblasts. The populations from these two regions were shown to differ in four allozyme loci (Ahd-2, Gpi, Es-5, and Dia-2). Within Kirov oblast, the samples from three tributaries of the Vyatka River differed in three other loci (Ck-1, Gp-9, and Trf). It is suggested that these features of the allele distribution at these loci are explained by the history of the introduced populations, hybridization between beavers from Voronezh oblast and Belarus, and founder effect during the subsequent artificial and spontaneous migration. Generally, genetic differences between the populations in all studied loci were very small: D = 0.02 between populations from different regions and D = 0.01 between populations from the tributaries of third-order rivers of the Kirov oblast. At the same time, disequilibrium was detected for ten polymorphic loci in the combined sample from the populations of Kirov oblast, which indicates the existence of interpopulation heterogeneity at the level of local populations of fourth- and fifth-order rivers. The unexpected finding of a genetic similarity between one studied individual of Tuvinian beaver subspecies (Castor fiber tuvinicus) and C. f. orientoeuropeas was recorded.     

Phylogeny of rheusus monkeys (Macaca mulatta) as revealed by mitochondrial DNA restriction enzyme analysis

Mitochondrial DNA, purified from 36 samples of 23 local populations which are widely distributed in Vietnam, Burma, and 10 provinces of China, has been analyzed to model the phylogeny of rhesus monkeys. The 20 local populations of China may represent nearly all major populations in China. Using 20 restriction endonucleases of 6-bp recognition, we observed a total of 50–61 sites in the various samples. By combining the cleavage patterns for each enzyme, the 36 samples were classified into 23 restriction types, each of which was found exclusively in the respective population from which samples were obtained. By combining the earlier study of Indian rheusus monkeys, phylogenetic trees, which have been constructed on the basis of genetic distance, indicate that rhesus monkeys in China, Vietnam, India, and Burma can be divided into seven groups. Integrating morphological and geographical data, we suggest that rhesus monkeys in China, Vietnam, and Burma may be classified into six subspecies—M. m. mulatta, M. m. brevicaudus, M. m. lasiotis, M. m. littoralis, M. m. vestita, and M. m. tcheliensis-and rhesus monkeys in India may be another valid subspecies.M. m. tcheliensis is the most endangered subspecies in China. Divergence among subspecies may have begun 0.9–1.6 Ma. The radiation of rhesus monkeys in China may have spread from the southwest toward the east. The taxonomic status of the Hainan monkey and the Taiwan monkey require further investigation.     

A review of flying fishes of the subgenus Hirundichthys (genus Hirundichthys, exocoetidae). 1. Oceanic species: H. speculiger, H. indicus sp. nova

A systematic revision of flying fishes of the subgenus Hirundichthys s.str was carried out based on a study of meristic and morphometric traits and characteristics of pigmentation of fishes from the local populations of species belonging to the subgenus. It is found out that the subgenus includes four species: oceanic H. speculiger from the Atlantic, Pacific and Indian Oceans, oceanic H. indicus sp.n. from the waters of the Indian Ocean, nerito-oceanic H. oxycephalus from the waters of the Indo-West Pacific and nerito-oceanic H. affinis from the Atlantic Ocean. The first part of the review focuses on two oceanic species with a large “mirror” on the pectoral fins: H. speculiger and H. indicus. A comparison of local populations showed that the species H. indicus is polytypic and consists of two subspecies. One of the subspecies—nominative H. indicus indicus—is distributed in the western and the central parts of the Indian Ocean and the other—H. indicus orientalis ssp.n.—in the Eastern Indian Ocean. Maps showing a geographical distribution of the species and the subspecies in the World Ocean are drawn up.