A new species of the genus Anthonomus Germar, 1817 (Coleoptera, Curculionidae) from Altai with a list of the Russian species

A new mountain species, Anthonomus (Anthonomidius) dudkoi Legalov, sp. n. from Western Altai is described and illustrated. The new species is similar to A. germanicus Dieckmann, 1968 from Europe and Kazakhstan but differs in the dark body, wider pronotum, thinner and more sparse piliform scales on the body, and thinner less curved rostrum. A distribution map of species from the subgenus Anthonomidius is given. A list of species of Anthonomus includes 32 species from Russia is compiled.

Isolation and selection of bacteria inhibiting Streptococcus agalactiae causing dark-body disease on snakeskin gourami fish (Trichogaster pectoralis)

Streptococcus agalactiae is one of the microbial pathogens causing the dark-body disease on snakeskin gourami fish (Trichogaster pectoralis) that affects the growth and quality of fish. This research aimed to isolate and select bacteria inhibiting S. agalactiae which are able to use for controling pathogenic bacteria instead of antibiotics. Fourteen bacteria strains were isolated and screened from healthy fishes, sediment and water samples at fish ponds in Dong Thap province. Among these strains, L7 strain showed the highest inhibition ability with the clear zone diameter was 9,3 mm. The results of the 16S rRNA sequence analysis indicated that the L7 strain belonged to Bacillus subtilis. The experiment to evaluate the inhibition capacity and fish disease control of selected B. subtilis in experimental conditions was conducted by challenging fish with S. agalactiae. Fishes in the control treatment was infected with S. agalactiae at 106 CFU/mL had survival rate 41,7%. The experimental treatments NT1, NT2, NT3 which were treated with B. subtilis at concentrations of 105 CFU/mL, 106 CFU/mL, and 107 CFU/mL gave higher survival rates compared with the non-treated control, with the rates of 60%, 76,7%, and 81,7%, respectively. These results revealed that the isolated B. subtilis is potential used in control dark-body disease on snakeskin gourami fish.

A new insular species of the Cyrtodactylus pulchellus group (Reptilia, Gekkonidae) from Tarutao Island, southern Thailand revealed by morphological and genetic evidence

The bent-toed geckos of the Cyrtodactylus pulchellus group are widely distributed along the Thai-Malay Peninsula. Although taxonomic and phylogenetic studies of this species group have been continuously conducted, only some populations from Thailand have been included, resulting in hidden diversity within this group. In this study, we used morphological and molecular data to clarify the taxonomic status and describe a new population from Tarutao Island, Satun Province, southern Thailand. Cyrtodactylus stellatussp. nov. can be distinguished from its congeners by the combination of the following morphological characters: body size; tuberculation; number of dark body bands, ventral scales, and femoroprecloacal pores in males; presence of precloacal pores in females; and scattered pattern on dorsum. Phylogenetic analyses of the mitochondrial ND2 gene recovered the new species as the sister species to C. astrum, with an uncorrected pairwise divergence of 9.78–12.37%. Cyrtodactylus stellatussp. nov. is currently only known from Tarutao Island, Thailand. The discovery of this species suggests that the diversity within the C. pulchellus group remains underestimated and future exploration of unsurveyed areas are needed to further the understanding of this group and its geographic range.

In the Line of Fire: Debris Throwing by Wild Octopuses

Wild octopuses at an Australian site frequently propel shells, silt, and algae through the water by releasing these materials from their arms while creating a forceful jet from the siphon held under the arm web. These "throws" occur in several contexts, including interactions with conspecifics, and material thrown in conspecific contexts frequently hits other octopuses. Some throws appear to be targeted on other individuals and play a social role, as suggested by several kinds of evidence. Such throws were significantly more vigorous and more often used silt, rather than shells or algae, and high vigor throws were significantly more often accompanied by uniform or dark body patterns. Some throws were directed differently from beneath the arms and such throws were significantly more likely to hit other octopuses. Throws targeted at other individuals in the same population, as these appear to be, are the least common form of nonhuman throwing.

Description of a New Species of Pelagic Eelpout Melanostigma thalassium sp. nova (Zoarcidae) from Walvis Ridge (Southeastern Atlantic) and Identification Key for Species of the Genus from the Atlantic Ocean

A new species Melanostigma thalassium sp. n. is described from the underwater Walvis Ridge (Southeast Atlantic Ocean). This species differs from the other species of the genus Melanostigma in an original combination of characters based on the structure of the head’s lateral line system (interruption in supratemporal commissure with the loss of medial segments and the absence of pores in the temporal canal) and a nontransparent dark body. In addition, it is different in a range of the count characters in the axial skeleton and fins. A key for identifying the Atlantic species of the genus is provided.

Nemesis, Tyche, Planet Nine Hypotheses. I. Can We Detect the Bodies Using Gravitational Lensing?

In this paper, the hypothesis of the existence of a massive dark body (Nemesis, Tyche, Planet Nine, or any other trans-Plutonian planet) at the Solar system periphery is analysed. Basic physical properties and orbital characteristics of such massive bodies are considered. The problem of the definition of a scattering angle of a photon in the gravitational field of a spherical lens is studied. It is shown that, the required value of the scattering angle can be measured for the cases of Nemesis and Tyche. The formation of gravitational lensing images is studied here for a point mass event. It is demonstrated that in most cases of the close rapprochement of a source and the lens (for Nemesis and Tyche), it is possible to resolve two images. The possibility of resolving these images is one of the main arguments favouring the gravitational lensing method as its efficiency in searching for dark massive objects at the edge of the Solar System is higher than the one corresponding to other methods such as stellar occultation. For the cases of Planet Nine and any other trans-Plutonian planet, the strong gravitational lensing is impossible because at least one of the images is always eclipsed.

Redescription of Panaqolus purusiensis(LaMonte, 1935) (Siluriformes: Loricariidae) with identification key to the species of the genus

Despite Panaqolus purusiensis being described nearly 80 years ago, very little is known about it. The taxon was described based on a single specimen. Researching collection catalogues has revealed two more specimens that were caught together along with the holotype but had subsequently been deposited in different museums. Recent collections, including one from the type locality, have made more specimens available. Examination of this new material reveals that this species has three distinct color patterns that are size dependent. Specimens with standard length (SL) less than 30 mm show a coloration common among various species of Panaqolus consisting of regular bands on the body, fins and head. Specimens from 30-90 mm SL have a specific color pattern with thinner bands and those larger than 90 mm SL have a uniformly dark body with only the fins continuing to show bands. The most similar species are P. changae, P. gnomus, P. maccus, and P. nocturnus.The first three can easily be distinguished by their coloration and by body proportions. Specimens of P. nocturnusof more than 90 mm SL however are nearly indistinguishable from P. purusiensisof the same size, making identification difficult.

Molecular phylogenetic relationships of the Liolaemus rothi complex and a new species of lizard from Auca Mahuida Volcano (Squamata: Liolaemini)

A new species of lizard of the genus Liolaemus from Neuquén Province, western Argentina, is described. The new species is a member of the Liolaemus rothi species complex, and mitochondrial and nuclear molecular data show it as sister taxon of the clade composed of (L. hermannunezi (L. tromen + L. loboi)), differing in size, squamation, coloration, and sexual dimorphism from the other species of this group. Liolaemus sitesi sp. nov. has a dark body coloration with series of notched blotches on the dorsum, with bright spots, and a very iridescent yellow-green coloration in natural light. Liolaemus sitesi sp. nov. is found only in the Auca Mahuida volcano and is terrestrial, dwelling on the stony slopes with sandy soil between 1300 m and the volcano summit.