Description of the male and first-stage juvenile of Longidorus intermedius Kozlowska & Seinhorst, 1979 (Nematoda: Dorylaimida), and notes on its morphology and distribution

Longidorus intermedius Kozlowska & Seinhorst, 1979 is redescribed from specimens recovered from oak (Quercus L.) forests in Bulgaria. The male and the first-stage juvenile were recorded for the first time, as were populations from Macedonia and Turkey. L. intermedius is identified here as the first species in the genus with only three juvenile stages and a pan-European distribution. The species was recovered from 36 of 46 oak forests in Bulgaria, found associated with each of nine oak species sampled and reached population densities of up to 289 specimens per 200 cm(3) of soil. The distribution of L. intermedius in Bulgaria, and in other countries, suggests that this species, like Xenocriconemella macrodora (Taylor, 1936) and probably L. aetnaeus Lamberti, Agostinelli & Vinciguerra, 1986, can be used as an ecological indicator for habitats where Quercus associations represent a primary vegetation type.     

Quantitative genetic diversity and conservation strategies for an allogamous annual species,Dasypyrum villosum (L.) Candargy (Poaceae)

Dasypyrum villosum (L.) Candargy is a weedy annual diploid (2n = 14, VV genomes) allogamous grass species (Poaceae, Triticeae). Genetic variation for 12 traits was studied in 43 natural populations (31 from Italy and 12 from Croatia and Montenegro of former Yugoslavia) grown in a common field environment in California. Although 7 of 12 traits followed the theoretical prediction that a larger proportion of genetic variation was distributed within populations than among populations, exceptions were found for spike length, plant height, and days to flag-leaf emergence, heading, and anthesis. Covariate analysis showed that developmentally closely related characters were more likely correlated at both population and family within population levels. Geographically closer populations shared more genetic similarity than distant populations as indicated by mean coefficients of variation and cluster analysis of the Euclidean distances among populations. As few as five populations, each population with five or more half-sib seeds taken randomly from 5 plants, is expected to capture more than 95% of the total genetic variation of this species in the region sampled, but sampling a much larger number of seeds per population (> 1000) for long-term storage would supply research and plant breeding needs for several decades. If seed regeneration is required, populations can be sampled from clusters having similar genetic variation, and grown in reproductive isolation or bulked seed samples from all populations of each cluster group can be grown in isolation. The former is recommended if population integrity is desired while the latter is sufficient to provide genetic resources for plant-breeding purposes.     

Systematics and evolution of the Disa draconis complex (Orchidaceae)

The systematic status of Disa draconis (L.f.) Sw. is revised following extensive field studies of population variation in the Western Cape, South Africa. Principal component and cluster analyses revealed clear distinctions between populations from sandplain, semi-arid and montane environments. Diagnostic characters were found in each of the population clusters indicating the existence of a species complex, rather than a single taxon as in the current taxonomy. We propose, therefore, that the name D. draconis (L.f.) Sw. be restricted to the individuals of the sandplain populations from which the type was collected. We reinstate an earlier name, Disa harveiana Lindl., to describe the montane populations which possess several autapomorphic characters. We also show that the geographical variation in spur length and flowering time within this species can be partitioned into two geographically distinct subspecies: D. harveiana subsp. harveiana and D. harveiana subsp. longicalcarata Johnson & Linder. The populations from the semi-arid Karoo region were recognized as a distinct new species, Disa karooica Johnson & Linder, on the basis of their peculiar petal structure. A cladistic analysis indicated that the three species forming the D. draconis complex form a monophyletic and relatively specialized lineage within Disa sect. Coryphaea. The revised classification also has important conservation implications as D. draconis , previously considered a common species, is now restricted to a few highly threatened populations on the west coast near Cape Town.     

Longidorus poessneckensis Altherr, 1974 and L. piceicola Lišková, Robbins & Brown, 1997 (Nematoda: Longidoridae): new records from Poland and the first description of the L. poessneckensis male and a bivulval female

Longidorus poessneckensis Altherr, 1974 and L. piceicola Lišková, Robbins & Brown, 1997 (Nematoda: Longidoridae) represent new records from Poland. These two species are described and illustrated together with a male and bivulval female of L. poessneckensis. In its general morphology and morphometrics, the male of L. poessneckensis is similar to the females, but has a spicule 100 μm long and one adanal pair, two double and a row of six single ventromedian supplements. Comments on the differential diagnosis of L. poessneckensis and two morphologically related species, L. uroshis Krnjaić, Lamberti, Krnjaić, Agostinelli & Radicci, 2000 and L. macrosoma Hooper, 1961 are given.     

Longidorus paravineacola n. sp. (Nematoda: Longidoridae), a New Species from Arkansas

Longidorus paravineacola n. sp., described herein, was found in a survey of longidorids of Arkansas. It is a parthenogeneticspecies characterized by its long body (6.68-9.85 mm); slightly expanded and rounded head, head width 21-27 µm; odontostyle length 95-114 µm; guide ring 28-37 µm posterior to the head end; short rounded tail, and c'' = 0.6-1.0. Longidorus paravineacola n. sp. is similar to the amphimictic species L. vineacola Sturhan &Weischer, 1964; L. balticus Brzeski, Peneva &Brown, 2000; L. kuiperi Brinkman, Loof &Barbez, 1987; and parthenogenetic species L. crassus Thorne, 1974, which also occurred in the type locality.     

Taxonomic study on the genus Eremopyrum (Ledeb.) Jaub. et Spach (Poaceae) in Turkey

In this study, we examined whether a satisfactory infrageneric grouping in Eremopyrum (Ledeb.) Jaub. & Spach can be achieved with the help of cluster analysis based on external vegetative and floral morphological characters of specimens either gathered from the field or borrowed from various herbaria. Twenty morphological characters were chosen and scored for 36 populations representing the genus. The data were subjected to numerical taxonomic analyses, and a phenogram was obtained by applying Gower general similarity index. The results of this study suggest that there are basically five species in Turkey, namely E. triticeum (Gaertner) Nevski, E. orientale (L.) Jaub. & Spach, E. distans (K. Koch) Nevski, E. bonaepartis (Sprengel) Nevski, and E. confusum Melderis. For the first time a new variety, E. bonaepartis (Sprengel) Nevski. var. aristatum Cabi & Do?an, is proposed along with two new combinations: E. bonaepartis (Sprengel) Nevski. var. sinaicum (Steudel) Cabi & Do?an and E. confusum Melderis var. sublanuginosum (Drob.) Cabi & Dogan. An account of Eremopyrum in Turkey is given, including a key to the species and varieties, and a general indication of their distribution.     

Population genetic structure and history of fragmented remnant populations of the New England cottontail (<Emphasis Type="Italic">Sylvilagus transitionalis</Emphasis>)

The New England cottontail (Sylvilagus transitionalis) has suffered from extensive loss and fragmentation of its habitat and is now a species of conservation priority in the northeastern United States. Remnant New England cottontail populations currently occur in five geographically disjunct locations: southern Maine and southeastern New Hampshire (MENH); the Merrimack Valley in central New Hampshire (NH-MV); Cape Cod, Massachusetts (CC); parts of eastern Connecticut and Rhode Island (CTRI); and western Connecticut, southeastern New York and southwestern Massachusetts (CTNY). We used microsatellite genotyping to discern patterns of population structure, genetic variability, and demographic history across the species’ range and to assess whether the observed patterns are a consequence of recent habitat loss and fragmentation. Our findings show that the geographic populations are highly differentiated (overall F _ST = 0.145; P < 0.001). Using Bayesian clustering analyses, we identified five genetic clusters, which corresponded closely to the geographic populations, but grouped MENH & NH-MV together (ME/NH) and identified an isolated population in eastern Connecticut (Bluff Point). The genetic clusters showed little evidence of recent gene flow and are highly influenced by genetic drift. The CC and Bluff Point populations show signs they experienced a genetic bottleneck, whereas the ME/NH population shows evidence of ongoing decline. Populations in Bluff Point, CC, and ME/NH also show significantly reduced genetic variation relative to the other clusters (CTNY and CTRI without Bluff Point). Without immediate human intervention, the short-term persistence of New England cottontail populations in Maine, New Hampshire and Cape Cod is at great risk. Conservation efforts at this time should focus on within-population sustainability and eventually restoring connectivity among these isolated populations.     

Morphological variation and distribution of cytotypes in the diploid-tetraploid complex of the genus Dactylis L. (Poaceae) from Algeria

Morphological and cytological characters were analysed among thirty populations of the genus Dactylis L. from Algeria, to understand its infraspecific diversity. Principal Component Analysis using quantitative characters allowed discriminating the tetraploid populations into two subspecies, marina (Borrill) Greuter, localised on sea cliffs, and hispanica (Roth) Nyman, very widespread. Some individuals of these latest populations formed a distinct group, identified as subsp. glomerata Hayek. Three diploid taxa are described in the literature: subspecies santai Stebbins & Zohary, castellata Parker & Borrill and mairei Stebbins & Zohary that are considered as prevalent in Algeria, distributed in Tellian Atlas, in forest ecosystems within mesophytic habitats. Canonical Discriminant Analysis on natural populations and on experimental cultures showed two main groups: the first group corresponds to subspecies mairei, with a narrow distribution; the second one exhibits a wide morphological variability and belongs to santai type. Based on this study, a key to aid in identification of the subspecies is presented.     

Polyploid origin,genetic diversity and population structure in the tetraploid sea lavender <Emphasis Type="Italic">Limonium narbonense</Emphasis> Miller (Plumbaginaceae) from eastern Spain

Limonium narbonense Miller is a fertile tetraploid species with a sporophytic self-incompatibility system. This sea lavender is found in coastal salt marshes which have been under intense human pressure during the past decades resulting in significant habitat fragmentation. Eleven microsatellite loci specifically designed for this species were amplified in 135 individuals from five populations. These markers were used to investigate the polyploid nature, the levels of genetic diversity and population structure in this species. L. narbonense showed high levels of genetic diversity (A = 7.82, P = 100% H _T = 0.446), consistent with its likely autotetraploid origin revealed in this study and obligate outcrossing breeding system. Inbreeding (F _IS) values were low in the three southern populations (mean F _IS = 0.062), and higher in the northern populations (mean F _IS = 0.184). Bayesian analysis of population structure revealed that populations could be grouped into two genetic clusters, one including three southern populations and the other the two northernmost ones. Individuals from the two northernmost populations showed higher admixture of the two genetic clusters than individuals from the three southern ones. A thorough analysis of microsatellite electrophoretic patterns suggests an autotetraploid origin for L. narbonense. The genetic structure revealed in this study is attributed to a recent migration from the southern area. This result suggests a net gene flow from the south to the north, likely facilitated by migratory movements of birds visiting the temporary flooded ponds occupied by L. narbonense.     

Molecules and morphology reveal a new aberrant harvestman genus of Ortholasmatinae (Opiliones,Dypsnoi, Nemastomatidae) from Mexico

Ortholasmatinae is one of the most striking groups of Opiliones, because its members exhibit a peculiar dorsal ornamentation pattern of cells, formed by fusion of anvil-shaped tubercles. During the systematic revision of several specimens of ortholasmatines, we found specimens with shared morphological characters with two genera Trilasma Goodnight & Goodnight, 1942 and Dendrolasma Banks, 1894. In order to investigate their phylogenetic relationships, we performed model-based phylogenetic analyses using the mitochondrial protein-encoding cytochrome c oxidase subunit 1 (CO1) and the complete nuclear ribosomal small subunit 18S, including members of the five genera of this subfamily. The results support the creation of Cryptolasma Cruz-López, Cruz-Bonilla & Francke, gen. nov., and two new species: Cryptolasma aberrante Cruz-López, Cruz-Bonilla & Francke, sp. nov. (type species) and Cryptolasma citlaltepetl Cruz-López, Cruz-Bonilla & Francke, sp. nov., which are from Xalapa and Orizaba Volcano, Veracruz, respectively. Additionally, our results suggest Ruaxphilos petrukenvitchou Goodnight & Goodnight, 1945 is a nomina dubia. This study represents the first molecular hypothesis of Ortholasmatinae relationships, with Cryptolasma as the sister of the remaining ortholasmatine.www.zoobank.org/urn:lsid:zoobank.org:pub:3730EE48-9802-4B06-9DDF-EC1AFE9A3B61     

Mitochondrial nucleotide variability in invasive populations of the root weevil Diaprepes abbreviatus (Coleoptera: Curculionidae) of Florida and preliminary assessment of Diaprepes sp. from Dominica

Diaprepes abbreviatus (L.) (Coleoptera: Curculionidae) is a root weevil introduced into the United States from the Caribbean in 1964. It is associated with >300 plants, including citrus, sugarcane, and potatoes. D. abbreviatus is widespread in Florida, and it has recently been detected in limited areas of California and Texas. The purpose of this research is to evaluate the utility of 16S ribosomal (16S rRNA) and cytochrome oxidase I (COI) mitochondrial markers for the delineation of genetic populations of D. abbreviatus in Florida and for the characterization of patterns of dispersion among these populations. We also assessed these markers as genetic tools for the clarification of taxonomic uncertainties in specimens from Dominica (Lesser Antilles). We analyzed 111 weevils from six Florida populations and six specimens from Dominica. In Florida, we found three haplotypes with only one haplotype in each population. Florida haplotypes differed by one to three nucleotide substitutions, possibly the result of a recent divergence from one source population or three different introductions from closely related populations from the Caribbean. In contrast, specimens from Dominica showed a high genetic variability with three 16S haplotypes and six unique COI haplotypes, delineating two mitochondrial clades. We show that these mitochondrial markers are useful for phylogeographic studies of D. abbreviatus.     

On the species of Gymnorhamphichthys Ellis, 1912, translucent sand‐dwelling Gymnotid fishes from South America (Pisces,Cypriniformes, Gymnotoidei)

Gymnorhamphichthys hypostomus and Gymnorhamphichthys rondoni are species with considerable variation in the length of the snout and in the position of the anal pore. A total of three hundred and thirty specimens were examined, including the holotype and 9 paratypes of Gymnorhamphichthys hypostomus Ellis, 1912, the single holotype of Urumara rondoni A. de Miranda Ribeiro, 1920, and the holotype and 20 paratypes of Gymnorhamphichthys hypostomus petiti Géry & Vu, 1964. A total of 205 specimens were measured: 1 from Bolivia, 34 from Brazil, 125 from Surinam, 13 from Guyana, 6 from Venezuela, and 26 from Colombia. The results are presented mostly in tables and diagrams, with a short discussion of the most variable characters.     

5S rDNA chromosomal mapping and COI sequence analysis reveal differentiation among distinct populations of a characid fish <Emphasis Type="Italic">Serrapinnus notomelas</Emphasis>

Cheirodontinae comprises a small-sized fish group with a wide geographical distribution throughout Central and South America, mainly in Brazilian Basins. The species Serrapinnus notomelas is widely distributed in the Upper Parana River Basin. In this work, chromosomal mapping of 5S ribosomal RNA (rRNA) gene was performed trough fluorescence in situ hybridization (FISH) in speciemens from three distinct localities belonging to two basins in the São Paulo State. All populations presented 5S clusters in two chromosome pairs. One additional pair was detected in samples from the Rio Paraitinguinha (Tietê Basin), and two additional pairs were detected in the population from Córrego Campo Novo (Tietê Basin). Analyses with partial sequences of COI were performed to verify the interelationship among the studied specimens, revealing Córrego Campo Novo population as a sister-group to the clade formed by the two other populations. The samples from Rio Paraitinguinha and Recanto dos Cambarás presented two distinct haplotypes each, while five haplotypes were observed in the Córrego Campo Novo population, sugesting that this could be older than the other populations. None of the nine haplotypes were shared among the three populations. The similarities and differences observed among the three populations using cytogenetic data and COI analysis are not related to geographic distances that separate the samples, suggesting that the origin of the Rio Paraitinguinha and Recanto dos Cambarás populations may be related to faunal exchanges. Additionally, the present data suggest that the analyzed populations of S. notomelas may be on independent evolutionary trajectories but in a very initial diversification stage. Moreover, the use of integrative information, such as molecular and chromosomal data in the analysis of population divergence and evolutionary trajectories in freshwater fishes is reinforced.     

阿蠓属一新种及一中国新记录种（昆虫纲：双翅目：蠓科）

本研究整理了2018年至2021年海南岛采集的阿蠓属Alluaudomyia昆虫标本,结合形态学特征和DNA条形码进行物种鉴定,首次记录了环纹阿蠓种团the annulata group在我国分布,鉴定发现了该种团内一新种拟环纹阿蠓Alluaudomyia pseudannulata Wu & Li sp. nov.,及一中国新记录种环足阿蠓Alluaudomyia annulipes Wirth & Delfinado, 1964。详细描述了两种阿蠓的形态特征,提供了鉴定特征图、海南岛物种分布图以及CO I条形码。     

Inter and intra-specific hybridization in tuco-tucos (Ctenomys) from Brazilian coastal plains (Rodentia: Ctenomyidae)

The present work describes chromosomal polymorphisms in zones of contact between divergent populations of Ctenomys minutus parapatrically distributed in the coastal plain of southern Brazil, and inter-specific hybridization with C. lami a closely related species. A sample of 171 specimens from 32 sample sites distributed along 161 km of the coastal plain was cytogenetically analyzed. Nine polymorphic populations were found: four with specimens with 2n = 46–48 (autosomal arm number (AN) = 76); three only have specimens with 2n = 47 and 48; one population sampled presented specimens with 2n = 43–46 (AN = 74–76) and one population with 2n = 50–52 (AN = 76–80). The remainder populations were fixed for 2n = 42, 46 or 48. The variation is the result of Robertsonian mechanisms of chromosomal evolution and a fusion in tandem rearrangement. The polymorphisms have been considered the result of secondary contact of populations after divergence in allopatry. The geomorphological evolution of the coastal plain provides clues to the possible existence of past geographic barriers acting over populations of Ctenomys, during the Holocene.     

Ontogenic study of the brachiopod Dicoelosia by geometric morphometrics and morphing techniques

The distinctive brachiopod Dicoelosia King 1850 is characterized by a strongly bilobed outline. To date, studies have concentrated on its functional morphology, taxonomy and evolution; little attention has been paid to its ontogeny. Here, we map population variation by principal component analysis for over 80 specimens distributed across five species of Dicoelosia. Using geometric morphometrics with landmarks for some 40 specimens, the ontogenic trends in D. sp. nov. are compared with those of Dicoelosia biloba. In addition, the ontogenic pathway in D. sp. nov. is investigated by morphing with control points, a new technique introduced here to palaeontology. Combining the results above, the ontogeny of the key character of the genus, emargination, is modelled. Within single populations, taxa may develop from broad weakly emarginate forms into those that are elongate and deeply emarginate. As the identification of the genus and its species depends on external morphological characters, the definition of ontogenetic trends in each species is essential for taxonomic discrimination. Substantial population variation exists in many of its species; however, the morphing technique provides a method of simulation, predicting the full range of ontogenetic variation in given populations.     

Sylvatic and peridomestic populations of Triatoma pseudomaculata are not significantly structured by habitat,as revealed by two genetic markers

Chagas disease remains a public health concern in Brazil and other Latin American countries, mainly due to the potential domiciliation of native triatomine species. We analyzed the genetic variability of Triatoma pseudomaculata in sylvatic and peridomestic ecotopes throughout three localities in the northeastern state of Bahia, Brazil. We studied polymorphisms generated by random amplified polymorphic DNA (RAPD) and isoenzyme electrophoresis analyses. Based on RAPD analysis, each specimen was assigned to one of three genetic clusters. Although all sylvatic specimens from one locality were grouped into the same cluster, sylvatic and peridomestic specimens from the other two localities were broadly distributed between the remaining two clusters, suggesting that geographic population structuring was not occurring. Furthermore, isoenzyme analysis suggested that distinct populations were in Hardy‐Weinberg equilibrium. Low statistical values for Wright's Fst index also supported the absence of population structuring and suggested the occurrence of panmixia. We conclude that genetic flow occurs between sylvatic and peridomestic T. pseudomaculata populations, probably as a consequence of passive and active dispersion of the insects, associated with deforestation and anthropic transformations.