Taxonomy and conservation: a tale of two tinamou species groups (Tinamidae,Crypturellus)

Species delimitation has important consequences for the management of endangered species. Species‐level taxonomy in the genus Crypturellus (Tinamidae) has been based largely on plumage characters and species limits in several groups have been difficult to establish. Because some of the forms of uncertain taxonomic status are currently threatened with extinction, a basic understanding of species limits is crucial not only for taxonomists but also for conservation biologists and managers. We analysed vocal variation to assess species limits in two Crypturellus species‐groups, the red‐legged complex (Crypturellus erythropus and allied forms) and the brown tinamou Crypturellus obsoletus. In the red‐legged complex, where several species‐level taxa have been recognized by some authors, there is no obvious geographic variation in vocalizations and populations appear mostly continuously distributed, with plumage variation largely explicable in terms of environmental conditions. In the brown group, a single species is recognized, but we found marked geographic variation in vocalizations and populations have disjunct distributions; we propose that at least one of the populations in this group likely merits recognition as a separate species. We conclude that incomplete knowledge of patterns of variation in relevant traits in addition to the momentum carried by traditional taxonomy may potentially mislead conservation actions.     

Morphological study of Eudromoxyura aspiculuris (Nematoda,Heteroxynematidae) from the tinamou Eudromia elegans (Aves,Tinamidae)

Eudromoxyura aspiculuris (Boero &; Led, 1971) is a parasite of a tinamid bird in Argentina. This is the type and only one known speices so far described in the genus Eudromoxyura Anderson &; Prestwood, 1972. It is here redescribed, and Eudromoxyura elonbyrdi Anderson &; Prestwood 1972 is considered a synonym. The morphological characters and systematic position of the genus Eudromoxyura are discussed. The genera Syphaciella (Mönning, 1920) and Eudromoxyura, the only oxyurids known parasitising birds, have probably arisen independently.     

Geometric morphometrics of the skull of Tinamidae (Aves, Palaeognathae)

The Tinamidae comprise exclusively Neotropical palaegnathous birds, with homogeneous body morphology and no sexual dimorphism. The goal of this work was to explore the variation in skull morphology between taxa and its possible correspondence with features such as diet or gender using geometric morphometric tools. Eleven landmarks were analyzed in 53 skulls of 4 genera that inhabit grasslands: Nothoprocta, Eudromia, Nothura and Rhynchotus. Intrageneric and intergeneric variability was analyzed. The genera studied here can be distinguished based on the geometric shape of their skull, with prenarial region length and neurocranium shape as the most outstanding features. In the genus Eudromia, males and females could be differentiated, while in the genus Nothoprocta, the species differentiated according to their trophic habits. This study allows establishing that genera and, in some cases, the gender of the Tinamidae can be differentiated based on cranial shape.     

The anatomy of the middle ear of the tinamiformes (Aves: Tinamidae)

The morphology of the middle ear region including the basicranium and quadrate of tinamous is compared among ratites and flying birds belonging to the Procellariiformes, Sphenisciformes, Pelecaniformes, and Ciconiiforms. The middle ears of tinamous and ratites share a number of important characters including absence of a separate foramen for the glossopharyngeal nerve; eustachian tube, carotid artery, and stapedial artery encased in bone; and a metotic process with vascular canals or notches. Outgroup analysis confirms these characters as synapomorphies. These data support the position that the Tinami and Ratiti form a monophyletic assemblage.     

Allometric relations in three species of finches (Aves: Fringillidae)

Static nestling, adult and ontogenetic allometry were analysed in three species of finches. Static nestling allometry was very similar across age in early ontogeny and among species and could be approximated by a single matrix of phenotypic variances and covariances. The first eigenvector of this matrix showed negative allometry of bill and tarsus to mass, but positive for wing length to mass. Adult static allometry was also very similar among species, but differed from nestling pattern. In adults the bill had a positive allometry in relation to tarsus and wing, but negative to mass, while tarsus and wing were unrelated to mass. The ontogenetic allometry in each species was very similar to nestling static allometry. Viewed in relation to final size, bill characters grew more slowly than body characters, but for a longer time, which created the difference between adult and nestling allometric patterns. There were differences among species both with regard to elevation and slope of allometric coefficients, suggesting that the differences among species came about by changes in the three fundamental ontogenetic parameters namely growth rate, onset of growth and offset of growth.     

A New Species of Allosathes Gaud, Atyeo & Berla (Astigmata: Crypturoptidae) on Feathers of the Chilean Tinamou, Nothoprocta perdicaria (Tinamiformes: Tinamidae) in Chile

Allosathes anitae n. sp. Casanueva & González-Acu?a (Astigmata: Crypturoptidae), collected on the Chilean tinamou Nothoprocta perdicaria (Tinamiformes: Tinamidae) from different localities of the ?uble Province, Chile, is described. Comments on its affinities and differences with Allosathes anepiandrius Gaud, Atyeo & Berla are also included.     

Tissue specific isozyme expression in three species of icterinae (Aves: Emberizidae)

Tissue specific banding patterns were examined for ten enzyme systems in three species of the subfamily Icterinae, family Emberizidae — Quiscalus quiscula, Agelaius phoeniceus and Molothrus ater. Ten tissues were compared. Generally, tissue specific patterns observed were remarkedly similar as compared to other taxa, across the three species over all enzyme systems examined, indicating low levels of divergence in regulatory genes. This concurs with other observations of conservative avian protein evolution as indicated by small comparative electrophoretic distances between species.     

The helminth infracommunities in three species of herons (Aves: Ardeidae) from Ukraine

This survey analysed the helminth communities associated with three Ukrainian heron species (Ardea cinerea, Ardea purpurea, Nycticorax nycticorax) collected throughout 1947–2019. The sample analysed included 128 specimens, and 55 helminth species were identified. Of these, the most diverse taxonomic group was trematodes with 29 species, followed by cestodes with 14 species, nematodes with nine, and acanthocephalans with three species. The helminth infracommunities were found to be similar across all three host species. Furthermore, the distance to the coastal regions impacts both diversity and species richness in infracommunities.     

Comparative study of selenium requirements of three phytoplankton species: Gymnodinium catenatum, Alexandrium minutum (Dinophyta) and Chaetoceros cf. tenuissimus (Bacillariophyta)

This study investigated the selenium (SE) requirements of three phytoplankton species which commonly bloom in southern Australian estuaries. The present study showed that the toxic dinoflagellate Gymnodinium catenatum Graham had an obligate requirement for Se (IV) in culture. After two transfers (4 weeks = 7 generations) in Se-deficient seawater medium, this phytoplankton species exhibited a decline in growth rate (25%) and biomass yield (90%), while complete cessation of cell division occurred under prolonged (8 weeks = 12 generations) Se starvation. Addition of 10^-9-10^-7 M H2SeO3 to nutrient-enriched seawater medium resulted in increased G.catenatum growth and biomass yields in direct proportion to the Se concentrations offered. In contrast to G.catenatum, Se limitation was observed in the dinoflagellate Alexandrium minutum Halim after four transfers (5 weeks = 20 generations) in Se-deficient medium. Exponential growth rates of A.minutum decreased slightly (5-10%) when Se was not supplied, but biomass yields decreased as much as 80-90%. The diatom Chaetoceros cf. <It>tenuissimus Meunier showed no evidence of Se limitation even after eight transfers (8 weeks; >60 generations) in Se-deficient medium. Variations in growth rates and biomass yields between transfers provide valuable information about the relative potential for Se limitation in the three species studied. In addition, differences in Se requirement between these bloom-forming phytoplankton species suggest that this micronutrient may play a role in structuring phytoplankton communities in southern Australian waters.      

Comparative cytogenetics of three species of Dichotomius (Coleoptera, Scarabaeidae)

Meiotic and mitotic chromosomes of Dichotomius nisus, D. semisquamosus and D. sericeus were analyzed after conventional staining, C-banding and silver nitrate staining. In addition, Dichotomius nisus and D. semisquamosus chromosomes were also analyzed after fluorescent in situ hybridization (FISH) with an rDNA probe. The species analyzed had an asymmetrical karyotype with 2n = 18 and meta-submetacentric chromosomes. The sex determination mechanism was of the Xy(p) type in D. nisus and D. semisquamosus and of the Xy (r) type in D. sericeus. C-banding revealed the presence of pericentromeric blocks of constitutive heterochromatin (CH) in all the chromosomes of the three species. After silver staining, the nucleolar organizer regions (NORs) were located in autosomes of D. semisquamosus and D. sericeus and in the sexual bivalent of D. nisus. FISH with an rDNA probe confirmed NORs location in D. semisquamosus and in D. nisus. Our results suggest that chromosome inversions and fusions occurred during the evolution of the group.     

Comparative study on the gametophyte morphology and development of three paramo species of Jamesonia (Pteridaceae,Polypodiopsida)

The sexual phase of three species of Jamesonia (J. imbricata, J. rotundifolia and J. scammaniae) has been studied, from spore germination to gametangia formation, with special attention to the morphological development of prothalli. This is the first work to deal with gametophytes of species in this genus. All three species have trilete, tetrahedrical spores that germinate following the Vittaria type. The developmental pattern of J. imbricata and J. rotundifolia is intermediate between the Adiantum and Ceratopteris types, as the initial mitotic activity is assumed by an obconical apical cell, substituted later by a lateral meristem. In J. scammaniae, no apical cell or lateral meristem is formed, so the prothalli remain ameristic throughout the developmental process. Adult gametophytes are naked and variable in shape, in the same species ranging from typical cordate prothalli to irregularly lobed forms. Gametangia of normal shape and size was observed in both J. imbricata and J. rotundifolia, but not in J. scammaniae. Apogamy could be expected to occur in the genus, a phenomenon to be examined in the future. Comparisons are made with known species of related genera and results are discussed from an ecological perspective in the paramo environment.     

双斑截尾寄蝇对寄主种类及草地螟幼虫龄期和寄生部位的选择性

双斑截尾寄蝇Nemorilla maculosa Meigen是草地螟和其他鳞翅类昆虫的重要寄生天敌,但国内外对其寄生行为知之甚少。为了明确双斑截尾寄蝇的寄生行为特征及其对草地螟种群动态的影响,在22℃,光照16 h的条件下就其对不同寄主种类及草地螟幼虫龄期、寄主部位的选择性进行了研究。结果显示：在草地螟、甜菜夜蛾和粘虫3种幼虫同时存在的条件下,双斑截尾寄蝇对草地螟的寄生率显著高于甜菜夜蛾和粘虫,而对甜菜夜蛾的寄生率又显著高于粘虫。另外,幼虫被寄生的平均次数也呈现相同的趋势,表明双斑截尾寄蝇喜选择草地螟。在3, 4, 5龄草地螟幼虫同时存在时,双斑截尾寄蝇对5龄幼虫的寄生率和平均寄生次数均显著高于4龄和3龄幼虫的,表明该寄蝇主要选择5龄幼虫为其寄主。在被寄生的草地螟幼虫中,胸部被寄生的比率（66.4%）和次数（4.2）显著高于头部（23.4%,1.0）和腹部（10.9%,1.1）,而腹部及头部被寄生的比例及卵粒数没有显著差异,表明双斑截尾寄蝇主要选择幼虫的胸部进行寄生。最后,就双斑截尾寄蝇对产卵寄主选择的原因和机理进行了讨论。     

Molecular phylogenetics, vocalizations, and species limits in Celeus woodpeckers (Aves: Picidae)

Species limits and the evolutionary mechanisms that have shaped diversification of woodpeckers and allies (Picidae) remain obscure, as inter and intraspecific phylogenetic relationships have yet to be comprehensively resolved for most genera. Herein, we analyzed 5020 base pairs of nucleotide sequence data from the mitochondrial and nuclear genomes to reconstruct the evolutionary history of Celeus woodpeckers. Broad geographic sampling was employed to assess species limits in phenotypically variable lineages and provide a first look at the evolution of song and plumage traits in this poorly known Neotropical genus. Our results strongly support the monophyly of Celeus and reveal several novel relationships across a shallow phylogenetic topology. We confirm the close sister relationship between Celeus spectabilis and the enigmatic Celeus obrieni, both of which form a clade with Celeus flavus. The Mesoamerican Celeus castaneus was placed as sister to a Celeus undatus-grammicus lineage, with the species status of the latter drawn into question given the lack of substantial genetic, morphological, and vocal variation in these taxa. We recovered paraphyly in Celeus elegans; however, this result appears to be the consequence of mitochondrial introgression from Celeus lugubris considering the monophyly of elegans at the ?-FIBI7 locus. A second instance of paraphyly was observed in Celeus flavescens with deep genetic splits and substantial phenotypic variation indicating the presence of two distinct species in this broadly distributed lineage. As such, we advocate elevation of Celeus flavescens ochraceus to species status. Our analysis of Celeus vocalizations and plumage characters demonstrates a pattern of lability consistent with a relatively recent origin of the genus and potentially rapid speciation history.     

Comparative study on the behavioral response to starvation in three species of antlion larvae (Neuroptera: Myrmeleontidae)

To clarify how pit-building antlion larvae behave during prolonged periods of low resource abundance, pit relocation rate, giving-up time, and respiration rate under starvation conditions were examined, using three species of antlion larvae. Most larvae ofMyrmeleon bore never relocated their pits before they starved to death, while larvae ofHagenomyia micans relocated more often thanMyrmeleon formicarius (average number of pit relocations 0.04 forM. bore, 0.19 forM. formicarius, and 0.62/individual/10 days forH. micans). The relative respiration rate, a ratio of respiration rate at starvation to that at satiation, was lower inM. bore andM. formicarius than in H. micans. Thus, there was an inversely proportional relationship between the pit relocation rate and the decrease in respiration rate under starvation conditions in the three species of antlion larvae.     

The skeletal kinematics of lung ventilation in three basal bird taxa (emu, tinamou, and guinea fowl)

In vivo visceral and skeletal kinematics of lung ventilation was examined using cineradiography in two palaeognaths, the emu (Dromaius novaehollandiae) and the Chilean tinamou (Nothoprocta perdicaria), and a basal neognath, the helmeted guinea fowl (Numida meleagris). Upon inspiration, the thorax expands in all dimensions. The vertebral ribs swing forward and upward, thereby increasing the transverse diameter of the trunk. The consistent location of the parapophysis throughout the dorsal vertebral series, ventral and cranial to the diapophysis, ensures a relatively uniform lateral expansion. An increase in the angle between the vertebral and the sternal ribs causes the sternal ribs to push the sternum ventrally. Owing to the greater length of the caudal sternal ribs, the caudal sternal margin is displaced further ventrally than the cranial sternal margin. When observed in lateral view, sternal movement is not linear, but elliptical. The avian thorax is highly constrained in its movement when compared with crocodylians, the other extant archosaur clade. Birds lack a lumbar region and intermediate ribs. Sternal ribs are completely ossified, and have a bicondylar articulation with the sternum. Considering the importance of pressure differences between cranial and caudal air sac complexes for the generation of unidirectional air flow in the avian lung, it is hypothesized that a decrease in the degrees of freedom of movement of the avian trunk skeleton, greater expansion of the ventrocaudal trunk region, and elliptical sternal movement may represent specific adaptations for fine-tuned control over air flow within the complex avian pulmonary system.     

Molecular systematics and species limits in the Philippine fantails (Aves: Rhipidura)

Islands have long-attracted scientists because of their relatively simple biotas and stark geographic boundaries. However, for many islands and archipelagos, this simplicity may be overstated because of methodological and conceptual limitations when these biotas were described. One archipelago that has received relatively little recent attention is the Philippine islands. Although much of its biota was documented long ago, taxonomic revision and evolutionary study has been surprisingly scarce, and only a few molecular phylogenetic studies are beginning to appear. We present a molecular phylogeny and taxonomic revision for the Philippine fantails (Aves: Rhipidura) using nuclear and mitochondrial DNA sequences. Our results suggest that current taxonomy underestimates diversity in the group. Some morphologically distinct subspecies warrant species status, whereas one was indistinguishable genetically and morphologically and should not be retained. A few taxa require additional sampling for thorough taxonomic assessment. Patterns of diversity within Philippine Rhipidura mostly corroborate predictions of the Pleistocene aggregate island complex (PAIC) hypothesis, in which diversity is expected to be partitioned by deep water channels separating Pleistocene aggregate islands rather than by current islands. Substantial structure within PAIC clades indicates that additional drivers of diversification should be considered.     

A species tree for the Australo-Papuan Fairy-wrens and allies (Aves: Maluridae)

We explored the efficacy of species tree methods at the family level in birds, using the Australo-Papuan Fairy-wrens (Passeriformes: Maluridae) as a model system. Fairy-wrens of the genus Malurus are known for high intensities of sexual selection, resulting in some cases in rapid speciation. This history suggests that incomplete lineage sorting (ILS) of neutrally evolving loci could be substantial, a situation that could compromise traditional methods of combining loci in phylogenetic analysis. Using 18 molecular markers (5 anonymous loci, 7 exons, 5 introns, and 1 mitochondrial DNA locus), we show that gene tree monophyly across species could be rejected for 16 of 18 loci, suggesting substantial ILS at the family level in these birds. Using the software Concaterpillar, we also detect three statistically distinct clusters of gene trees among the 18 loci. Despite substantial variation in gene trees, species trees constructed using four different species tree estimation methods (BEST, BUCKy, and STAR) were generally well supported and similar to each other and to the concatenation tree, with a few mild discordances at nodes that could be explained by rapid and recent speciation events. By contrast, minimizing deep coalescences produced a species tree that was topologically more divergent from those of the other methods as measured by multidimensional scaling of trees. Additionally, gene and species trees were topologically more similar in the BEST analysis, presumably because of the species tree prior employed in BEST which appropriately assumes that gene trees are correlated with each other and with the species tree. Among the 18 loci, we also discovered 102 independent indel markers, which also proved phylogenetically informative, primarily among genera, and displayed a ～4-fold bias towards deletions. As suggested in earlier work, the grasswrens (Amytornis) are sister to the rest of the family and the emu-wrens (Stipiturus) are sister to fairy-wrens (Malurus, Clytomyias). Our study shows that ILS is common at the family level in birds yet, despite this, species tree methods converge on broadly similar results for this family.