Geographic Distribution and Conservation of Cactaceae from Tamaulipas Mexico

An inventory of the species of Cactaceae from Tamaulipas, Mexico was carried out. The study area was divided into 48 squares of 30 min of latitude and 30 min of longitude. Collections were made at 60 sampling sites distributed over an area extending in to the bordering states of San Luis Potosí, Nuevo León, Veracruz and Texas (USA). Species diversity per squares and their geographic distribution range were obtained. Results showed a diversity of 120 species and 53 subspecies, of total 49 are considered as endangered by the CITES, IUCN, and SEMARNAT. The genera most represented were Mammillaria, Coryphantha, Echinocereus and Opuntia. Index of Geographical Expansion (IGE) was calculated for each species. Highest diversity per squares as well as the IGE for each species was found at square 66 (Jaumave) IGE = 52%, 72 (Tanque Blanco) IGE = 22% and 59 (Cd. Victoria) IGE = 7%. It was for these sites that had the highest number of endemic taxa and thus are recommended as priority sites for conservation. This information may help establish natural protected areas by the government of the State of Tamaulipas.     

Echinoids (Echinodermata: Echinoidea) from the Gulf of Mexico

The echinoid fauna of the Gulf of Mexico collected during three research cruises (20-1260 m depth) was surveyed from samples were taken at 43 stations. A total of 190 individuals were identified (eight orders, 11 families, 15 genera and 18 species). Six species are new records for the Gulf of Mexico: Stylocidaris lineata, Phormosoma placenta placenta, Plesiodiadema antillarum, Plethotaenia spatangoides, Brissopsis atlantica and Hypselaster limicolus. This adds to the little information available on the echinoid fauna of Tamaulipas, Veracruz, Tabasco, Campeche and Yucatan states in Mexico.     

Aphyllon castilloi sp. nov. (Orobanchaceae) from Veracruz,Mexico

Aphyllon castilloi Franc.‐Gut., Cházaro & Espejo (Orobanchaceae), a new species discovered in central Veracruz, Mexico is herein described, illustrated and compared with other Aphyllon species recorded from Mexico. The new species inhabits tropical semideciduous forest, a novel ecosystem for Aphyllon species native to North America, in contrast to most collections from Mexico, which are from warm sandy deserts. In addition, it parasitizes Simsia foetida (Asteraceae: Heliantheae). As far as known, the distribution of the new species is very restricted.     

Association of Vibrio cholerae with plankton in coastal areas of Mexico

The El Niño event of 1997/1998 provided an opportunity to carry out a field experiment in which the relationship of sea surface temperature and the association of Vibrio cholerae with marine plankton could be assessed in Mexican coastal and estuarine areas. Plankton samples were collected from May 1997 through June 1999. Sites included the Mexican ports of Veracruz, Coatzacoalcos and Frontera in the Gulf of Mexico and Ensenada, Guaymas, Mazatlán, Manzanillo, Acapulco and Oaxaca in the Pacific Ocean. Sampling was also accomplished during two oceanographic cruises in the Yucatan channel of the Caribbean Sea. Bacteriological analyses for V. cholerae serogroups O1 and O139 were carried out. Also, the taxonomic structure of the plankton populations was determined. Vibrio cholerae O1 was detected only in Veracruz samples collected during April, May and June 1999, when La Niña climatic conditions prevailed. It is concluded that V. cholerae O1 in Mexico derives from its marine and estuarine origin and not from sewage contamination. The significant number of Acartia tonsa copepodites and V. cholerae copepodite-positive samples suggests a significant role of this copepod in the occurrence and distribution of V. cholerae in coastal areas of Mexico.     

Distribution and variation of Dion edule (Zamiaceae)

Dion edule is distributed through the Sierra Madre Oriental from Veracruz to Nuevo León and in dijunct stations in Tamaulipas. The most significant variation consists in the reduction of leaflet width from the south northwards. On this basis, two varieties are recognized:D. edule var.edule, characterized by wide leaflets and a distribution in Veracruz, Hidalgo, Querétaro, San Luis Potosí and southern Tamaulipas, andD. edule var.angustifolium, with narrow leaflets and a distribution in central-northern Tamaulipas and Nuevo León.     

Extended jurisdiction and the management of Pacific highly migratory species

Abstract

The Pacific region is the most important producer of tropical tuna in the world. Three subregions account for the production: Pacific Latin America, the Pacific Islands region, and Southeast Asia. Prior to the UN Third Conference on the Law of the Sea, the Tuna Fisheries in the subregions were the preserve of developed distant water fishing nations. The situation has now been entirely reversed, with coastal state jurisdiction and control being realized in all three subregions. It is argued that American opposition to coastal state jurisdiction over tuna resources acted as a goad to the coastal states in Pacific Latin America and the Pacific Islands region in their quest for greater control over tuna resources. There are prospects of cooperation developing among the three Pacific subregional tuna producers. It is argued further that American action may have inadvertently accelerated the progress toward cooperation.     

Global population structure of the spiny dogfish Squalus acanthias,a temperate shark with an antitropical distribution

The spiny dogfish (Squalus acanthias) is a temperate, coastal squaloid shark with an antitropical distribution in the Atlantic and Pacific oceans. The global population structure of this species is poorly understood, although individuals are known to undergo extensive migrations within coastal waters and across ocean basins. In this study, an analysis of the global population structure of the spiny dogfish was conducted using eight polymorphic nuclear microsatellite markers and a 566‐bp fragment of the mitochondrial ND2 gene region. A low level of genetic divergence was found among collections from the Atlantic and South Pacific basins, whereas a high level of genetic divergence was found among Pacific Ocean collections. Two genetically distinct groups were recovered by both marker classes: one exclusive to North Pacific collections, and one including collections from the South Pacific and Atlantic locations. The strong genetic break across the equatorial Pacific coincides with major regional differences in the life‐history characters of spiny dogfish, suggesting that spiny dogfish in areas on either side of the Pacific equator have been evolving independently for a considerable time. Phylogeographic analyses indicate that spiny dogfish populations had a Pacific origin, and that the North Atlantic was colonized as a result of a recent range expansion from the South American coast. Finally, the available data strongly argue for the taxonomic separation of the North Pacific spiny dogfish from S. acanthias and a re‐evaluation of the specific status of S. acanthias is warranted.     

The mosquitoes (Diptera: Culicidae) of Tabasco,Mexico

To document and update the mosquito species of Tabasco, Mexico, field collection trips were conducted in the two physiographic regions of Tabasco: the coastal plain of the southern gulf and the mountains of Chiapas and Guatemala. Mosquitoes were collected as immature and adult stages during the dry and rainy seasons from 2014 through 2015. Additionally, the Reference Collection of Arthropods of Medical Importance (CAIM‐InDRE) containing mosquitoes of Tabasco was re‐examined. In total, 4,913 specimens were collected and examined, which are divided into seven tribes, 18 genera, 27 subgenera, and 104 species. Of these, one genus (Shannoniana Lane and Cerqueira), two subgenera (Georgecraigius Reinert, Harbach and Kitching, and Carrollia Lutz), and 21 species are new records for the mosquito fauna of Tabasco. Culex metempsytus Dyar is a new record for Mexico and Wyeomyia jocosa (Dyar and Knab) is removed from the Mexican mosquito fauna. Seventeen species historically reported were not found in the field collections conducted here. Taxonomic notes, new distribution limits, and comments about the medical importance of species of mosquitoes of Tabasco are discussed. Tabasco is the second state in Mexico with the largest mosquito richness (104 species), followed by Veracruz with 139 species.     

Significance of new records of Tridacna squamosa Lamarck, 1819, in the Tuamotu and Gambier Archipelagos (French Polynesia)

The giant clam subfamily Tridacninae (family Cardiidae) is an important group of bivalve molluscs found throughout the Red Sea and Indo-Pacific, from East Africa to the Eastern Pacific biogeographic region. The Tridacna genus is currently revised with numerous cryptic species identified with molecular markers. New Tridacna records from the fringe of the known distribution areas are extremely useful to identify genetically unique species, geographic ranges, and to examine processes associated with species differentiation. While Tridacna maxima is abundant in French Polynesia (Central South Pacific Ocean) the larger fluted giant clam Tridacna squamosa was formerly reported only in the Austral Islands in the south. Following a recent survey that spanned 23 islands and atolls of the Society, Tuamotu and Gambier Archipelagos, the presence of T. squamosa between the Cook Islands and Pitcairn Islands is confirmed using both morphological and molecular information, suggesting a relic distribution across the Central Pacific Ocean. Tridacna squamosa is rare, but present throughout Tuamotu and Gambier. However, it remained undetected from the Society Islands, probably due to historical over-fishing. This species is valued by local inhabitants, and is sought after mainly as gifts and also for a limited local shell trade. The rarity of T. squamosa may call for conservation measures in the near future.     

Molecular biogeography and origins of the Hawaiian fern flora

Located approximately 4000 km from the nearest continent, the Hawaiian Islands comprise the most isolated archipelago on Earth. This isolation has resulted in a unique flora that includes nearly 200 native ferns and lycophytes, 77% of which are endemic to the islands. Because the Hawaiian Islands are volcanic in origin, all abiotically dispersed organisms must have arrived there via the wind or the water. Fern spores are most likely dispersed through the air, and thus patterns of air movement have undoubtedly played a significant role in determining the geographic origins of the ancestors of the Hawaiian ferns. We have identified four possible climate-based or weather-based spore dispersal hypotheses that could have resulted in the movement of ancestral spores to the Hawaiian Islands: (1) the northern subtropical jetstream, moving spores from Indo-Pacific regions; (2) the trade winds, dispersing spores from Central and North America; (3) storms carrying spores from southern Mexico and/or Central America; and (4) a dispersal mechanism carrying spores from the South Pacific across the equator resulting from the combined influence of a seasonal southern shift of the Intertropical Convergence Zone (ITCZ), Hadley Cell air movement, and the trade winds. Utilizing recently published molecular phylogenetic studies of three fern genera (Dryopteris, Polystichum, andHymenophyllum) and new analyses of three additional genera (Adenophorus, Grammitis, andLellingeria), each of which is represented in the Hawaiian Islands by at least one endemic lineage, we reviewed the biogeographical implications for the Hawaiian taxa in light of the possible common dispersal patterns and pathways. We hypothesize that three of the five endemicDryopteris lineages, both of the endemicPolystichum lineages, at least one endemicHymenophyllum lineage in the Hawaiian Islands, and, perhaps, one endemicGrammitis lineage resulted from ancestral spores of each lineage dispersing to the Hawaiian Islands via the northern subtropical jetstream.Adenophorus is sister to a mostly neotropical clade, therefore, it is likely that the ancestor of the Hawaiian clade dispersed to the Hawaiian Islands via the trade winds or a storm system. The ancestor of the endemicLellingeria lineage may have dispersed to the Hawaiian Islands from the neotropics via the trade winds or a storm system, or from the South Pacific across the equator through the combination of a seasonal southern shift of the ITCZ, Hadley Cells, and the trade winds.     

Reproduction and morphology of Central American and Tres Marias spinner dolphins in the eastern tropical Pacific

Four geographic forms of spinner dolphin (Stenella longirostris) occur in the eastern tropical Pacific. Two of the forms are pelagic: the eastern and whitebelly, and two are coastal: the Central American and Tres Marias spinner dolphins. Of these, only the Tres Marias form lacks recognition appropriate for developing management and conservation plans. Vertical aerial photographs of 57 spinner dolphin schools taken between 1988 and 2006 were used to examine the range of coastal forms and to characterize their calving seasons. On the basis of adult body length, spinner dolphins photographed off Guerrero, Mexico, were identified as those of the Central American form, which is north of their known range, and those photographed farther north, approximately 112 km off Nayarit, Mexico, were identified as the Tres Marias form. Calving peaked from October through March, and there was evidence that calving seasons differed among geographic forms with coastal forms calving later than pelagic forms. We present the first life history parameter estimates for the coastal forms of spinner dolphins, provide additional support for recognition of the Tres Marias form, and the first evidence of the Central American form occurring north of the Gulf of Tehuantepec, Mexico.     

PHYLOGEOGRAPHY OF THE SPOTTED SAND BASS, PARALABRAX MACULATOFASCIATUS: DIVERGENCE OF GULF OF CALIFORNIA AND PACIFIC COAST POPULATIONS

Abstract Have the warm tropical waters and currents of the southern Gulf of California, Mexico (also known as the Sea of Cortez), formed a barrier to gene flow, resulting in disjunct populations in the upper gulf that are isolated from the outer Pacific Coast? Phylogeographic and genetic divergences of the spotted sand bass, Paralabrax maculatofasciatus, from three Gulf of California and two outer Pacific coastal locations were tested using mitochondrial DNA (mtDNA) control region sequences. Sequence data from two congeners that are sympatrically distributed along the outer Pacific Coast, the barred sand bass, P. nebulifer, and the kelp bass, P. clathratus, were used to gauge the levels of genetic divergences. Differences among the three species and between the northern gulf and outer Pacific coastal populations of P. maculatofasciatus also were analyzed using 40 allozymic presumptive gene loci. Allozyme and mtDNA analyses each revealed many fixed differences among the species. Three significant allozymic frequency differences and two fixed mtDNA substitutions differentiated the gulf and outer Pacific coastal populations of P. maculatofasciatus. Three unique mtDNA haplotypes and three unique allozyme alleles were identified from the outer Pacific coastal population. The gulf sites contained four unique mtDNA haplotypes and six unique allozyme alleles. Partitioning of the mtDNA variation revealed that 72% of the variance occurred between the gulf and outer Pacific Coast, 20% between sampling sites in the two regions, and 8% within the sites. There appears to be little gene flow across the waters of the southern Baja Penninsula, producing divergence estimated as 120,000 to 600,000 years between the outer Pacific coastal and the Gulf of California populations. This separation level may date to a hypothesized seaway closure near La Paz, Mexico, during the mid‐Pleistocene, and characterizes other fish populations. A second pattern of deeper allopatric species‐level divergences in some other fishes may date to a Pliocene closure of a mid‐Baja Penninsular seaway. Significant differences also were discerned in P. maculatofasciatus between the San Diego and central Baja California coastal sites and between the upper/central and the lower gulf locations. Variation between locations in the two regions may be indicative of larval retention and low adult migration, which needs to be tested further.     

Status of the eastern Pacific agujon needlefish Tylosurus pacificus (Steindachner, 1876) (Beloniformes: Belonidae)

Tylosurus pacificus (Steindachner, 1876) is confirmed to have full species rank based on: 1) sympatry with T. acus melanotus at Isla Gorgona and in Panamá; 2) level of morphological differentiation in numbers of vertebrae, dorsal and anal fin rays; and 3) level of mtDNA differentiation. The eastern Pacific agujon needlefish is found from the Gulf of California, Mexico, to Peru, including the Galápagos Islands.     

Revision of the Neotropical genus Leptochromus Motschulsky (Coleoptera: Scydmaenidae)

Abstract The Neotropical genus Leptochromus Motschulsky (Coleoptera: Scydmaenidae) is revised, and a phylogenetic analysis of Clidicini is presented. Leptochromus includes five species distributed from Veracruz, Mexico to Manaus, Brazil. Leptochromus fulvescens Motschulsky, L. mexicanus (Sharp) and L. agilis (Sharp) are considered valid species. Leptochromus bicolor O'Keefe, sp.n. from Veracruz, Mexico and L . palaeomexicanus O'Keefe, sp.n. from Miocene amber from Chiapas are described. Male genitalia and antennae are illustrated for each of the extant species. Female genitalia, mouthparts and other morphological features are illustrated for the type species L. fulvescens. For the phylogenetic analysis of Clidicini, Palaeoleptochromus O'Keefe was placed as the sister taxon to Leptochromus , and Papusus Casey was placed as the sister taxon to Leptochromus  + Palaeoleptochromus . Papusus is elevated from synonomy with Leptochromus and the biogeography of Clidicini is discussed.     

Affinities of the marine flora of the Revillagigedo Islands,Mexico

The benthic algal flora reported for the Revillagigedo Islands comprises 205 specific infraspecific taxa: 42 Chlorophyta, 29 Phaeophyta and 134 Rhodophyta. This insular flora shares 131 taxa (54%) with other regions of the Mexican Pacific and 74 (36%) are restricted apparently to the islands. One hundred three taxa (50%) are shared with areas of the Mexican tropical Pacific, 69 (34%) with warm temperate Pacific Mexico and 66 (32%) with La Paz, the transitional zone between tropical and warm temperate Pacific Mexico. Considering more general regions, the Revillagigedo Islands flora includes apparently restricted distribution (34 spp., 16.6%), exclusively tropical (51 spp., 25%) and widely distributed eastern Pacific (33 spp., 16%) taxa. Even though we consider that the inventory of the Revillagigedo Islands and to a lesser degree the eastern tropical Pacific flora is still incomplete and in need of further taxonomic study, the floristic comparison shows a greater affinity of the Revillagigedo Islands flora with the Mexican tropical Pacific than with any other part of Mexico.     

Distribution and species composition of juvenile and adult scombropids (Teleostei,Scombropidae) in Japanese coastal waters

Two scombropid fishes, Scombrops boops and Scombrops gilberti, are closely related and commercially important species in Japan. These species are often confused in commercial markets because of their morphological similarity. In this study, scombropid specimens collected from various Japanese coastal waters were subjected to polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) analysis and phylogenetic analysis of the 16S rRNA gene in mitochondrial DNA. These analyses showed that all the scombropid specimens collected from localities in the Sea of Japan were identified as S. boops, whereas those from the Pacific Ocean included two species, S. boops and S. gilberti. Almost all juvenile (<200 mm standard body length, S_L) S. gilberti originated from the Pacific coastal waters of the northern Japan, whereas adults (>400 mm S_L) were found only in deep water off the Izu Peninsula to the Izu Islands. This suggests that S. gilberti might migrate extensively during its life cycle. In addition, differences in the number of specimens and the distribution between the two species suggest that S. gilberti is less abundant than S. boops in Japanese waters.