A new species of Hisonotus (Siluriformes,Loricariidae) from rio S?o Francisco basin,Brazil

A new species of Hisonotus is described from the rio São Francisco basin. The new species can be distinguished from congeners by having (1) a unique coloration pattern of caudal fin with one black spot extending from its origin to the ventral lobe and two dark spots at the end of the lobe’s rays; (2) odontodes forming longitudinally aligned rows on head and trunk; (3) a functional V-shaped spinelet; (4) a single rostral plate at the tip of the snout; (5) by lacking contrasting dark geometric spots on the anterodorsal region of the body; (6) a lower caudal-peduncle depth; and (7) lower counts of the lateral median plates and (8) higher premaxillary and dentary teeth. The new species is the second described species of the genus Hisonotus in the rio São Francisco basin. It was found inhabiting the marginal vegetation of the rio São Francisco and three of its tributary, rio das Velhas, rio Paraopeba and rio Formoso.     

A new species of Sturisoma Swainson, 1838 (Loricariidae: Loricariinae), from the Madeira River basin,with a discussion of historical biogeography of western Amazonas and Paraguay River basins

A new loricariin species of Sturisoma is described from the Cautário, Guaporé, Mamoré, Machado and Soteiro rivers, Madeira River basin, in Bolivia and Brazil. The new species is distinguished from its congeners by the presence of a middorsal longitudinal, thin dark brown stripe on the caudal peduncle, extending from two or three plates posterior to the dorsal-fin base, reaching the origin of the caudal fin, or one or two plates anterior to the origin of the caudal fin; small squarish anteriormost abdominal plates; and a middorsal longitudinal dark-brown stripe from first predorsal plate to near the dorsal-fin origin. Furthermore, the new species is diagnosed from congeners by plate morphology, counts on the median series, coalescent plates and ventrolateral thoracic plates, in addition to measurements related to body and head structures. An analysis of genetic distances using cytochrome C oxidase subunit 1 gene marker of the mitochondrial genome between the new species and several congeners is presented, in addition to a likelihood analysis to illustrate the position of the new taxon within Sturisoma. An identification key for species of the genus currently recorded at the upper Amazonas River basin is provided.     

Description of two new species of Hisonotus Eigenmann & Eigenmann, 1889 (Ostariophysi,Loricariidae) from the rio Paraná-Paraguay basin,Brazil

Two new species of Hisonotus are described from the rio Paraná-Paraguay basin in Brazil. The most remarkable features of the new species are the odontodes forming longitudinally aligned rows (one odontode after the other, but not necessarily forming parallel series) on the head and trunk (vs. odontodes not forming longitudinally aligned rows), a pair of rostral plates at the tip of the snout (vs. a single rostral plate), the functional v-shaped spinelet (vs. spinelet non-functional, square-shaped, or absent). These features suggest close phylogenetic relationships with Hisonotus bockmanni, H. insperatus, H. luteofrenatus and H. piracanjuba. Additionally, both new species are distinguished from their congeners by characters related to head length and depth, orbital diameter, suborbital depth, caudal peduncle depth, pectoral-fin spine length, snout length and counts of teeth. Hisonotus paresi sp. n. further differs from its congeners by having contrasting dark geometric spots on the anterodorsal region of the body, a character lacking in H. oliveirai sp. n. The variation in number and shape of the rostral plate, posterior rostrum plates, infraorbitals and the preopercle in both new species and in H. insperatus are discussed.     

New species of the Pseudancistrus barbatus group (Siluriformes,Loricariidae) with comments on its biogeography and dispersal routes

A new species of Pseudancistrus is described from the Tapajós Basin, and assigned to the P. barbatus group by having hypertrophied odontodes along the snout and lacking evertible cheek plates. The new species is distinguished from other species in that group (P. barbatus, P. corantijniensis, P. depressus and P. nigrescens) by its pattern of spots, length and color of snout odontodes, greater head depth, cleithral width, anal-fin spine length, peduncle depth and internares width. Molecular phylogenetic results corroborate placement of the new species in the Pseudancistrus barbatus group which is otherwise distributed in the Xingu Basin and rivers draining the Guyana Shield into the Atlantic Ocean. Topology tests strongly reject alternative hypotheses supporting close relationships with Guyanancistrus, Lithoxancistrus or the species Pseudancistrus pectegenitor, P. sidereus and P. genisetiger. Additionally, we propose two hypotheses on the distribution of the new species in the rio Tapajós, a Brazilian Shield drainage. The first one proposes that ancestral stock of the P. barbatus group was widely distributed throughout rivers draining the Guyana and Brazilian shields, and the species P. zawadzkii and Pseudancistrus sp. L17 are in the limit of the distribution for the group in Tapajós and Xingu rivers. The second hypothesis proposes that ancestral stock of the P. barbatus group was restricted to Guyana Shield rivers, and that headwater capture events permitted several dispersal routs through Guyana and Amazon rivers, permitted that the ancestral lineages of Pseudancistrus sp. L17 and P. zawadzkii reached the rivers of Amazon basin.     

A new Liopropoma sea bass (Serranidae,Epinephelinae, Liopropomini) from deep reefs off Cura?ao,southern Caribbean,with comments on depth distributions of western Atlantic liopropomins

Collecting reef-fish specimens using a manned submersible diving to 300 m off Curaçao, southern Caribbean, is resulting in the discovery of numerous new fish species. The new Liopropoma sea bass described here differs from other western Atlantic members of the genus in having VIII, 13 dorsal-fin rays; a moderately indented dorsal-fin margin; a yellow-orange stripe along the entire upper lip; a series of approximately 13 white, chevron-shaped markings on the ventral portion of the trunk; and a reddish-black blotch on the tip of the lower caudal-fin lobe. The new species, with predominantly yellow body and fins, closely resembles the other two “golden basses” found together with it at Curaçao: L. aberrans and L. olneyi. It also shares morphological features with the other western Atlantic liopropomin genus, Bathyanthias. Preliminary phylogenetic data suggest that western Atlantic liopropomins, including Bathyanthias, are monophyletic with respect to Indo-Pacific Liopropoma, and that Bathyanthias is nested within Liopropoma, indicating a need for further study of the generic limits of Liopropoma. The phylogenetic data also suggest that western Atlantic liopropomins comprise three monophyletic clades that have overlapping depth distributions but different depth maxima (3–135 m, 30–150 m, 133–411 m). The new species has the deepest depth range (182–241 m) of any known western Atlantic Liopropoma species. Both allopatric and depth-mediated ecological speciation may have contributed to the evolution of western Atlantic Liopropomini.     

Alburnoides manyasensis (Actinopterygii,?Cyprinidae), a new species of cyprinid fish from?Manyas?Lake?basin,?Turkey

Alburnoides manyasensis, sp. n., is described from the Koca Stream (Lake Manyas drainage, Marmara Sea basin) in Anatolia. It is distinguished from all species of Alburnoides in Turkey and adjacent regions, Alburnoides tzanevi (Rezovska [Rezve], Istranca and Terkos streams in the western Black Sea drainage), Alburnoides cf. smyrnae (Banaz Stream, a drainage of Büyük Menderes River, Aegean Sea basin), Alburnoides fasciatus (streams and rivers in the eastern Black Sea drainage) and Alburnoides eichwaldii (Kura and Aras rivers [a drainage of Kura River], Caspian Sea basin) by a combination of the following characters (none unique to the species):marked hump at nape, especially in specimens larger than 60 mm SL; partly developed ventral keel between pelvic fin and anal fin, scaleless 1/2 to 2/3 its length; body depth at dorsal-fin origin 29−32% SL; caudal peduncle depth 11−12% SL; 45–52+ 2–3 lateral-line scales; 9–12 scale rows between lateral line and dorsal-fin origin; 4–5 scale rows between lateral line and anal-fin origin, 10½–12½ branched anal-fin rays; 40–42 total vertebrae.     

Connectivity across the Caribbean Sea: DNA Barcoding and Morphology Unite an Enigmatic Fish Larva from the Florida Straits with a New Species of Sea Bass from Deep Reefs off Cura?ao

Integrative taxonomy, in which multiple disciplines are combined to address questions related to biological species diversity, is a valuable tool for identifying pelagic marine fish larvae and recognizing the existence of new fish species. Here we combine data from DNA barcoding, comparative morphology, and analysis of color patterns to identify an unusual fish larva from the Florida Straits and demonstrate that it is the pelagic larval phase of a previously undescribed species of Liopropoma sea bass from deep reefs off Curaçao, southern Caribbean. The larva is unique among larvae of the teleost family Serranidae, Tribe Liopropomini, in having seven elongate dorsal-fin spines. Adults of the new species are similar to the golden bass, Liopropoma aberrans, with which they have been confused, but they are distinct genetically and morphologically. The new species differs from all other western Atlantic liopropomins in having IX, 11 dorsal-fin rays and in having a unique color pattern–most notably the predominance of yellow pigment on the dorsal portion of the trunk, a pale to white body ventrally, and yellow spots scattered across both the dorsal and ventral portions of the trunk. Exploration of deep reefs to 300 m using a manned submersible off Curaçao is resulting in the discovery of numerous new fish species, improving our genetic databases, and greatly enhancing our understanding of deep-reef fish diversity in the southern Caribbean. Oh the mother and child reunion is only a moment away. Paul Simon.     

Morphological variation of freshwater crabs Zilchiopsis collastinensis and Trichodactylus borellianus (Decapoda,Trichodactylidae) among localities from the middle Paraná River basin during different hydrological periods

Measures of hydrologic connectivity have been used extensively to describe spatial connections in riverine landscapes. Hydrologic fluctuations constitute an important macrofactor that regulates other environmental variables and can explain the distribution and abundance of organisms. We analysed morphological variations among individuals of two freshwater crab species, Zilchiopsis collastinensis and Trichodactylus borellianus, from localities of the middle Paraná River basin during two phases of the local hydrological regime. Specimens were sampled at sites (localities) of Paraná River, Saladillo Stream, Salado River and Coronda River when water levels were falling and rising. The conductivity, pH, temperature and geographical coordinates were recorded at each site. The dorsal cephalothorax of each crab was represented using 16 landmarks for Zilchiopsis collastinensis and 14 landmarks for Trichodactylus borellianus. The Canonical Variate Analyses showed differences in shape (for both species) among the crabs collected from the Paraná and Salado Rivers during the two hydrologic phases. We did not find a general distribution pattern for shape among the crab localities. During falling water, the shapes of Zilchiopsis collastinensis were not related to latitude-longitude gradient (i.e., showing greater overlap in shape), while during rising water the shapes were ordered along a distributional gradient according to geographical location. Contrary, shapes of Trichodactylus borellianus were related to latitude-longitude during falling water and were not related to distributional gradient during rising water. The cephalothorax shape showed, in general, no statistically significant covariations with environmental variables for either species. These results show that each freshwater crab species, from different localities of the middle Paraná River, remain connected; however, these connections change throughout the hydrologic regime of the floodplain system. This study was useful for delineating how the relation among shapes of crabs of localities varies during two phases of the hydrological regime and for estimating the connections and geographical patterns in the floodplain system.     

Description of a new perchlet,Chelidoperca formosa,from southwestern Taiwan (Peciformes: Serranidae)

A new perchlet species is described on the basis of four specimens collected from southwestern Taiwan. It is similar to congeners with relatively few lateral-line scales (35–38) and can be distinguished by having third to sixth dorsal-fin spines notably long; eighth and ninth dorsal-fin spines notably short; developed gill rakers 1 + 7–8; scale rows between lateral line and sixth dorsal-fin spine 4 (the dorsalmost half-sized); tip of upper corner of caudal fin reddish; four reddish bands midlaterally on body with groups of melanophores in these bands. DNA barcoding analysis reveals the new species is a distinct lineage and closest to Chelidoperca microdon. The average interspecific genetic distance calculated by the K2P model is 15.4%, whereas the mean distance from the new species to C. microdon is 18.3%. The inferred phylogenetic tree supports monophyly of Chelidoperca. Including the new species, six nominal species of Chelidoperca are recognized in Taiwanese waters.     

Evolutionary History of the Live-Bearing Endemic Allotoca diazi Species Complex (Actinopterygii,Goodeinae): Evidence of Founder Effect Events in the Mexican Pre-Hispanic Period

The evolutionary history of Mexican ichthyofauna has been strongly linked to natural events, and the impact of pre-Hispanic cultures is little known. The live-bearing fish species Allotoca diazi, Allotoca meeki and Allotoca catarinae occur in areas of biological, cultural and economic importance in central Mexico: Pátzcuaro basin, Zirahuén basin, and the Cupatitzio River, respectively. The species are closely related genetically and morphologically, and hypotheses have attempted to explain their systematics and biogeography. Mitochondrial DNA and microsatellite markers were used to investigate the evolutionary history of the complex. The species complex shows minimal genetic differentiation. The separation of A. diazi and A. meeki was dated to 400–7000 years ago, explained by geological and climate events. A bottleneck and reduction of genetic diversity in Allotoca diazi was detected, attributed to recent climate fluctuations and anthropogenic activity. The isolation of A. catarinae occurred ~1900 years ago. No geological events are documented in the area during this period, but the date is contemporary with P’urhépecha culture settlements. This founder effect represents the first evidence of fish species translocation by a pre-Hispanic culture of Mexico. The response of the complex to climate fluctuation, geological changes and human activity in the past and the future according to the ecological niches predictions indicates areas of vulnerability and important information for conservation. The new genetic information showed that the Allotoca diazi complex consist of two genetic groups with an incomplete lineage sorting pattern: Pátzcuaro and Zirahuén lakes, and an introduced population in the Cupatitzio River.     

Molecular data reveal a complex population genetic structure for Psalidodon scabripinnis (Teleostei: Characidae) in the Atlantic Rainforest,Brazil

Recently renamed, Psalidodon scabripinnis populations of Serra da Mantiqueira, previously known as Astyanax scabripinnis have been deeply studied in the last years. These populations are small and isolated and occur very close to the watershed between Paraíba do Sul River basin and Upper Paraná River basin, in Serra da Mantiqueira region in the Atlantic Rainforest. These conditions arouse the interest in knowing theor genetic conservation status and how they responded to the separation between the two rivers basins. Therefore, we accessed the genetic diversity of five P. scabripinnis populations of this region with microsatellites and mitochondrial data. The results showed a complex structure pattern that doesn’t match the simple basin separation and a reasonably conservation status when compared with other populations of the same family or with similar natural history.     

Hisonotus acuen,a new and phenotypically variable cascudinho (Siluriformes,Loricariidae, Hypoptopomatinae) from the upper rio Xingu basin,Brazil

A new species of Hisonotus is described from the headwaters of the rio Xingu. The new species is distinguished from its congeners by having a functional V-shaped spinelet, odontodes not forming longitudinal aligned rows on the head and trunk, lower counts of the lateral and median series of abdominal figs, presence of a single rostral fig at the tip of the snout, absence of the unpaired figlets at typical adipose fin position, yellowish-tipped teeth, absence of conspicuous dark saddles and stripe on the body and higher number of teeth on the premaxillary and dentary. The new species, Hisonotus acuen, is restricted to headwaters of the rio Xingu basin, and is the first species of the genus Hisonotus described from the rio Xingu basin. Hisonotus acuen is highly variable in aspects of external body proportions, including body depth, snout length, and abdomen length. This variation is partly distributed within and among populations, and is not strongly correlated with body size. PCA of 83 adult specimens from six allopatric populations indicates the presence of continuous variation. Therefore, the available morphological data suggest that the individuals inhabiting the six localities of rio Xingu represent different populations of a single species. Low intraspecific variation in mitochondrial Cytochrome oxidase subunit I (COI) provides corroborative evidence.     

Evoxymetopon moricheni,a new cutlassfish from the northern Red Sea (Teleostei: Trichiuridae)

Evoxymetopon moricheni n. sp. is described from the northern Gulf of Aqaba, Red Sea, on the basis of a single specimen. It is characterised within the genus by a convex upper head profile; the posterior confluence of the frontal ridges slightly elevated at the nape, resulting in the presence of a slight sagittal crest; eye 5.2 times in head length; the lower hind margin of opercle slightly pointed in its lower half; the pelvic fins reduced to a scale-like structure with two soft rays on the posterior process of the basipterygium, its origin below the eighth dorsal-fin element; the first anal spine single, oval, scale like, and originating a short distance behind the vent (opposite the 34th dorsal-fin soft ray), anterior anal-fin soft rays minute and embedded, barely penetrating the skin and not visible externally, while the posterior fin supporting the rays enlarged and visible externally; approximately 17 anal-fin rays externally visible; approximately 83 dorsal-fin elements, with first spine not elongate, shorter than second; 12 pectoral-fin rays (ii + 6 + iv), with shorter anterior (fourth ray shortest) and longer posterior rays extending above the lateral line; 10 upper and 13 lower gill rakers of the first gill arch; head and body silver white, with a blackish margin anteriorly on snout and head, continuing along the anterior half of the dorsal-fin base. The new finding represents a new record of the genus from the Red Sea.     

<Emphasis Type="Italic">Enneapterygius velatus</Emphasis>, a new deepwater triplefin (Perciformes: Tripterygiidae) from the Ryukyu Islands,southern Japan

A new deepwater species, Enneapterygius velatus sp. nov. (Perciformes: Tripterygiidae), is described from two male specimens from Ryukyu Island, southern Japan, the holotype having been collected at a depth of 55 m and an underwater photograph taken between 30 and 41 m depth. The new species is characterized by an extremely long first dorsal-fin spine (length 31.6–34.0 % of SL), the first dorsal-fin spine bases close together, first dorsal-fin base length less than half the distance between the base of the third spine of the first dorsal-fin and origin of second dorsal-fin, first dorsal-fin spine base with developed inclinator muscles, long pelvic fins (tip of second ray extending beyond anal-fin origin), large body scales (8 circumpeduncular scales), the supratemporal sensory canals deeply U-shaped in dorsal view, snout profile weakly rounded, abdomen from between pelvic-fin bases to anal-fin origin covered by cycloid scales, body lacking significant blackish blotches and caudal-fin base with scattered melanophores in preserved specimens.     

First 'Rauisuchian' archosaur (Pseudosuchia,Loricata) for the Middle Triassic Santacruzodon Assemblage Zone (Santa Maria Supersequence), Rio Grande do Sul State,Brazil

The ‘Rauisuchia’ are a group of Triassic pseudosuchian archosaurs that displayed a near worldwide distribution. In Brazil, their fossils are found only in the Santa Maria Formation (Paraná Basin) of the Rio Grande do Sul State, specifically in the Middle Triassic Dinodontosaurus assemblage zone (AZ) and the Late Triassic Hyperodapedon AZ (Rauisuchus tiradentes). Between these two cenozones is the Santacruzodon AZ (Middle Triassic), whose record was, until now, restricted to non-mammalian cynodonts and the proterochampsian Chanaresuchus bonapartei. Here we present the first occurrence of a rauisuchian archosaur for this cenozone, from the Schoenstatt outcrop, located near the city of Santa Cruz do Sul and propose a new species, based on biostratigraphical evidence and a comparative osteological analysis.     

Hitting an Unintended Target: Phylogeography of Bombus brasiliensis Lepeletier, 1836 and the First New Brazilian Bumblebee Species in a Century (Hymenoptera: Apidae)

This work tested whether or not populations of Bombus brasiliensis isolated on mountain tops of southeastern Brazil belonged to the same species as populations widespread in lowland areas in the Atlantic coast and westward along the Paraná-river valley. Phylogeographic and population genetic analyses showed that those populations were all conspecific. However, they revealed a previously unrecognized, apparently rare, and potentially endangered species in one of the most threatened biodiversity hotspots of the World, the Brazilian Atlantic Forest. This species is described here as Bombus bahiensis sp. n., and included in a revised key for the identification of the bumblebee species known to occur in Brazil. Phylogenetic analyses based on two mtDNA markers suggest this new species to be sister to B. brasiliensis, from which its workers and queens can be easily distinguished by the lack of a yellow hair-band on the first metasomal tergum. The results presented here are consistent with the hypothesis that B. bahiensis sp. n. may have originated from an ancestral population isolated in an evergreen-forest refuge (the so-called Bahia refuge) during cold, dry periods of the Pleistocene. This refuge is also known as an important area of endemism for several animal taxa, including other bees. Secondary contact between B. bahiensis and B. brasiliensis may be presently prevented by a strip of semi-deciduous forest in a climate zone characterized by relatively long dry seasons. Considering the relatively limited range of this new species and the current anthropic pressure on its environment, attention should be given to its conservation status.     

Lack of evolutionary adjustment to ambient temperature in highly specialized cave beetles

Background

A key question in evolutionary biology is the relationship between species traits and their habitats. Caves offer an ideal model to test the adjustment of species to their surrounding temperature, as they provide homogeneous and simple environments. We compared two species living under different thermal conditions within a lineage of Pyrenean beetles highly modified for the subterranean life since the Miocene. One, Troglocharinus fonti, is found in caves at 4-11°C in the ancestral Pyrenean range. The second, T. ferreri, inhabits the coastal area of Catalonia since the early Pliocene, and lives at 14-16°C.

Results

We found no differences in their short term upper thermal limit (ca. 50°C), similar to that of most organisms, or their lower thermal limit (ca. -2.5°C), higher than for most temperate insects and suggesting the absence of cryoprotectants. In longer term tests (7 days) survival between 6-20°C was almost 100% for both species plus two outgroups of the same lineage, but all four died between 23-25°C, without significant differences between them.

Conclusions

Our results suggest that species in this lineage have lost some of the thermoregulatory mechanisms common in temperate insects, as their inferred default tolerance range is larger than the thermal variation experienced through their whole evolutionary history.

Electronic supplementary material

The online version of this article (doi:10.1186/s12862-015-0288-2) contains supplementary material, which is available to authorized users.