Culaeatrema inconstans gen.n., sp.n. (Digenea: Alloereadiidae) from the brook stickleback (Culaea inconstans) in Wisconsin and observations on parthenogenetic populations

1988 ◽  
Vol 66 (6) ◽  
pp. 1328-1333 ◽  
Author(s):  
Becky A. Lasee ◽  
William F. Font ◽  
Daniel R. Sutherland
Keyword(s):  
New Species ◽  
Anterior Testis ◽  
Posterior Region ◽  
Culaea Inconstans ◽  
Parasitic Helminths ◽  
Reproductive Structures ◽  
Brook Stickleback ◽  
Two Populations

Culaeatrema inconstans gen.n., sp.n. is described from the intestine of Culaea inconstans (Kirtland) collected in Wisconsin. Culaeatrema is a small, fusiform, nonspinous trematode resembling both allocreadiins and bunoderins. Culaeatrema is placed in the subfamily Bunoderinae because testes are oblique in position, uterus extends into the posterior region, and vitellaria do not extend beyond the anterior testis. Reproduction in two populations of the new species from Shell and Little Waumandee creeks appears to be parthenogenetic. Parthenogenetic worms exhibited larger phenotypic size, one or both testes lacking in 84% of the examined specimens, lack of spermatozoa, and reduced development of male reproductive structures. A discussion of parthenogenesis in parasitic helminths is included.

Evidence for a trade-off between defensive morphology and startle-response performance in the brook stickleback (Culaea inconstans)

1995 ◽  
Vol 73 (6) ◽  
pp. 1147-1153 ◽  
Author(s):  
Gregory M. Andraso ◽  
James N. Barron
Keyword(s):  
Escape Response ◽  
Maximum Velocity ◽  
Predation Pressure ◽  
Small Displacement ◽  
Trade Off ◽  
Culaea Inconstans ◽  
Response Performance ◽  
Brook Stickleback ◽  
Two Populations ◽  
Deep Body

It is generally believed that predation pressure may drive the evolution of long spines, a robust pelvic girdle, and a deep body in sticklebacks (Pisces: Gasterosteidae). However, the lack of such traits in environments under intense predation pressure suggests that there may be a limit to which these apparently defensive structures benefit sticklebacks. In some environments, well-developed defensive structures may not increase stickleback survival, but may actually reduce fitness if there is a cost associated with them. This paper focuses on a trade-off between defensive morphology and escape-response performance in the brook stickleback (Culaea inconstans). Our study of four populations of brook stickleback reveals that the population with the largest pelvic girdles and deepest bodies has a poorly developed escape response (i.e., small displacement, low maximum velocity, and low acceleration), while the population with the smallest pelvic girdles and shallowest bodies has a highly developed escape response. The two populations with intermediate defensive structures are intermediate in escape-response performance. Consideration of predation regimes in different environments may help us understand selection pressures that favor heavily versus poorly armored stickleback morphs.

Persistence of pelvic spine polymorphism in a panmictic population of brook stickleback (Culaea inconstans) in Alberta, Canada

2020 ◽  
Vol 98 (10) ◽  
pp. 643-649
Author(s):  
J. Lowey ◽  
Q. Cheng ◽  
S.M. Rogers ◽  
J.A. Mee
Keyword(s):  
Reproductive Isolation ◽  
Balancing Selection ◽  
Environmental Disturbances ◽  
Culaea Inconstans ◽  
Pelvic Morphology ◽  
Niche Specialization ◽  
As Species ◽  
Selective Forces ◽  
Brook Stickleback ◽  
Two Populations

In the stickleback family (Gasterosteidae), divergence in pelvic morphology is typically associated with reproductive isolation and ecological niche specialization. In this study, we assessed whether reproductive isolation may be involved in the persistence of within-lake polymorphism in brook stickleback (Culaea inconstans (Kirtland, 1840)). We studied populations of brook stickleback in central Alberta, Canada, that are polymorphic for pelvic reduction (i.e., presence–absence of pelvic spines). We investigated the persistence of the pelvic polymorphisms over 40 generations in five lakes. We found that, of the five populations examined, the frequencies of pelvic phenotypes have remained unchanged in three populations, the polymorphism has persisted with significantly changed frequencies of pelvic phenotypes in one population, and the polymorphism has been lost in one population. Using 10 microsatellite loci, we observed low genetic divergence between individuals with and without pelvic spines in one lake, suggesting a lack of assortative mating among individuals with divergent pelvic phenotypes. This observation suggests that the pelvic polymorphism in brook stickleback persists due to balancing selection in the absence of reproductive isolation, although the selective forces were not evaluated. The significant changes in phenotypic frequencies in two populations are likely associated with environmental disturbances such as species introductions.

Paepalanthus fabianeae (Eriocaulaceae): A New Microendemic Species from a Morphologically Coherent Clade

2020 ◽  
Vol 45 (4) ◽  
pp. 794-801
Author(s):  
Caroline Oliveira Andrino ◽  
Marcelo Fragomeni Simon ◽  
Jair Eustáquio Quintino Faria ◽  
André Luiz da Costa Moreira ◽  
Paulo Takeo Sano
Keyword(s):  
New Species ◽  
Iucn Red List ◽  
Phylogenetic Position ◽  
Similar Species ◽  
Infrageneric Classification ◽  
Espinhaço Range ◽  
Nuclear Its ◽  
Two Populations

Abstract—We describe and illustrate Paepalanthus fabianeae, a new species of Eriocaulaceae from the central portion of the Espinhaço Range in Minas Gerais, Brazil. Previous phylogenetic evidence based on analyses of nuclear (ITS and ETS) and plastid (trnL-trnF and psba-trnH) sequences revealed P. fabianeae as belonging to a strongly supported and morphologically coherent clade containing five other species, all of them microendemic, restricted to the Espinhaço range. Due to the infrageneric classification of Paepalanthus being highly artificial, we preferred not assigning P. fabianeae to any infrageneric group. Paepalanthus fabianeae is known from two populations growing in campos rupestres (highland rocky fields) in the meridional Espinhaço Range. The species is characterized by pseudodichotomously branched stems, small, linear, recurved, and reflexed leaves, urceolate capitula, and bifid stigmas. Illustrations, photos, the phylogenetic position, and a detailed description, as well as comments on habitat, morphology, and affinities with similar species are provided. The restricted area of occurrence allied with threats to the quality of the habitat, mainly due to quartzite mining, justifies the preliminary classification of the new species in the Critically Endangered (CR) category using the guidelines and criteria of the IUCN Red List.

Geographic and morphological variation in the presence and absence of the pelvic skeleton in the brook stickleback, Culaea inconstans (Kirtland), in Alberta and Saskatchewan

1971 ◽  
Vol 49 (3) ◽  
pp. 343-352 ◽  
Author(s):  
Joseph S. Nelson ◽  
F. Mervyn Atton
Keyword(s):  
Morphological Variation ◽  
Fishery Management ◽  
Fish Introduction ◽  
Spine Length ◽  
Culaea Inconstans ◽  
Full Development ◽  
Normal Individuals ◽  
Brook Stickleback ◽  
Presence And Absence ◽  
Skeleton Formation

Brook sticklebacks, Culaea inconstans (Kirtland), are known from 20 locations in Alberta and Saskatchewan in which a high proportion of the individuals lack all or part of the pelvic skeleton. These locations are interspersed and surrounded by other locations containing individuals with a normal pelvic skeleton. Individuals which lack the skeleton are of both sexes and are fertile in at least one of the lakes.Considerable variation exists between locations in the proportion of individuals with and without the pelvic skeleton. Morphological intermediates are known from most of the 20 locations and virtually all degrees of pelvic skeleton formation exist between its absence and its full development. Little or no gradation exists, however, in pelvic spine length between their absence and presence. Although the pelvic spines are the first part of the pelvic skeleton to appear during ontogeny, they are present only in intermediates with a virtually complete skeleton base. In addition, many intermediates are highly asymmetrical in their pelvic skeleton while development during the ontogeny of normal individuals is symmetrical.There is a greater tendency for individuals in which the pelvic skeleton is deficient to occur in lakes which lack an outlet rather than to occur in lakes with a permanent outlet. An unusually high proportion of the lakes with these aberrant individuals have been subject to fishery management activities (fish introduction and poisoning), but these disturbances are not causing the loss of the pelvic skeleton.

Two new annual fishes (Cyprinodontiformes: Rivulidae) unexpectedly discovered in the highlands of southern Brazil

Zootaxa ◽  
2021 ◽  
Vol 4949 (3) ◽  
pp. 499-520
Author(s):  
LUIS ESTEBAN KRAUSE LANÉS ◽  
MATHEUS VIEIRA VOLCAN ◽  
LEONARDO MALTCHIK
Keyword(s):  
New Species ◽  
Conservation Status ◽  
The Body ◽  
Colour Pattern ◽  
Southern Brazil ◽  
Body Depth ◽  
Body Contact ◽  
Morphometric Features ◽  
Natural Grassland ◽  
Two Populations

Two new species of Austrolebias are described based on specimens collected from temporary pools located in natural grassland landscape within the Araucaria Forest domain at exceptionally high altitudes (~1000 meters a.s.l.). Austrolebias botocudo sp. n. and Austrolebias nubium sp. n. occur, respectively, in drainages of upper rio Apuaê-Inhandava (upper rio Uruguay basin) and upper rio Taquari-Antas (upper rio Jacuí, Laguna dos Patos basin), in the Meridional Plateau of southern Brazil. Despite an intensive survey conducted in the area, only two populations of each species were recorded. Both new species occurs at altitudes that are among the higher recorded for species of the genus, and both are assigned to the subgenus Acrolebias. The new species described herein are easily distinguished for its congeners by the colour pattern of males, by presence of melanophores irregularly distributed in different parts of the body, contact organs cover the body and anal fins, position of fins related with vertebrae, by preopercular and mandibular series of neuromasts united, by a series of morphometric features and by larger maximum standard length. Austrolebias botocudo and A. nubium are distinguished from each other by colour pattern of males, length of contact organs in the flank and number of contact organs in scales of lateral line, dorsal profile of head, number of neuromasts in the preopercular + mandibular series, body depth in females, and by basihyal cartilage length. Additionally, we discuss the conservation status of the new species, and provided an identification key for the species of the subgenus Acrolebias. 

Significant population genetic structure detected for a new and highly restricted species of Atriplex (Chenopodiaceae) from Western Australia, and implications for conservation management

2012 ◽  
Vol 60 (1) ◽  
pp. 32 ◽  
Author(s):  
Laurence J. Clarke ◽  
Duncan I. Jardine ◽  
Margaret Byrne ◽  
Kelly Shepherd ◽  
Andrew J. Lowe
Keyword(s):  
Genetic Variation ◽  
New Species ◽  
Genetic Structure ◽  
Western Australia ◽  
Sequence Data ◽  
Isolation By Distance ◽  
Conservation Strategies ◽  
New Taxon ◽  
Near Surface ◽  
Two Populations

Atriplex sp. Yeelirrie Station (L. Trotter & A. Douglas LCH 25025) is a highly restricted, potentially new species of saltbush, known from only two sites ~30 km apart in central Western Australia. Knowledge of genetic structure within the species is required to inform conservation strategies as both populations occur within a palaeovalley that contains significant near-surface uranium mineralisation. We investigate the structure of genetic variation within populations and subpopulations of this taxon using nuclear microsatellites. Internal transcribed spacer sequence data places this new taxon within a clade of polyploid Atriplex species, and the maximum number of alleles per locus suggests it is hexaploid. The two populations possessed similar levels of genetic diversity, but exhibited a surprising level of genetic differentiation given their proximity. Significant isolation by distance over scales of less than 5 km suggests dispersal is highly restricted. In addition, the proportion of variation between the populations (12%) is similar to that among A. nummularia populations sampled at a continent-wide scale (several thousand kilometres), and only marginally less than that between distinct A. nummularia subspecies. Additional work is required to further clarify the exact taxonomic status of the two populations. We propose management recommendations for this potentially new species in light of its highly structured genetic variation.

scholarly journals A new Palaearctic species of the subgenus Lunatipula (Diptera, Tipulidae) from the West Caucasus with a survey of the caucasica species group

ZooKeys ◽  
2021 ◽  
Vol 1048 ◽  
pp. 145-175
Author(s):  
Vladimir I. Lantsov ◽  
Valentin E. Pilipenko
Keyword(s):  
New Species ◽  
Parallel Evolution ◽  
Distribution Patterns ◽  
Species Group ◽  
Palaearctic Species ◽  
The West ◽  
The Caucasus ◽  
Males And Females ◽  
First Time ◽  
Two Populations

The caucasica species group in the subgenus Lunatipula is redefined and now consists of five species native to the Caucasus. Tipula (L.) eleniyasp. nov. is described as new to science, and variations in the male terminalia in two populations are noted. Two subspecies (quadridentataquadridentata and quadridentatapaupera) are elevated to species rank. Detailed photo’s complement the descriptions of all five species (caucasica, eleniya, paupera, quadridentata, talyshensis), and data on ecology and distribution patterns are included as well as identification keys to males and females. Tipula caucasica is recorded from the West Caucasus and Tipula quadridentata is recorded from Dagestan (Russia) for the first time. Parallel evolution is traced in the male terminalia of the new species and in several non caucasica species group of Palaearctic Lunatipula.

Molecular and morphological characterisation of Cryptaphelenchus baujardi n. sp. (Nematoda: Ektaphelenchinae), a new species based on two populations from Iran

Nematology ◽  
2019 ◽  
Vol 21 (1) ◽  
pp. 45-56 ◽  
Author(s):  
Farzad Aliramaji ◽  
Esmaeil Miraeiz ◽  
Ebrahim Pourjam ◽  
Ramin Heydari
Keyword(s):  
New Species ◽  
Phylogenetic Analyses ◽  
Lsu Rdna ◽  
New Taxon ◽  
Male Body ◽  
Northern Iran ◽  
Lateral Field ◽  
Rdna Sequences ◽  
Strong Resemblance ◽  
Two Populations

Summary Cryptaphelenchus baujardi n. sp. is described and illustrated based on two populations from Golestan province, northern Iran. The new species is characterised by female and male body length of 224 (190-261) and 215 (195-229) μm, respectively, offset cephalic region with a shallow constriction, delicate stylet 6.6 (6.0-7.0) μm long, four incisures in the lateral field, presence of a rudimentary post-uterine sac in the female gonoduct, elongate-conoid female tail ending in an acute to finely rounded terminus, male tail conical, male with seven caudal papillae and delicate spicules. The new species shows a strong resemblance to C. varicaudatus and C. iranicus, but has a sclerotised mass near the tip of the spicule and an indistinct spermatheca. Phylogenetic analyses based on both partial SSU and LSU rDNA sequences confirm its status as a new taxon.

Taxonomic status of two populations of Bent-toed Geckos of the Cyrtodactylus irregularis complex (Squamata: Gekkonidae) with description of a new species from Nui Chua National Park, southern Vietnam

Zootaxa ◽  
2018 ◽  
Vol 4403 (2) ◽  
pp. 307 ◽  
Author(s):  
OLIVIER S. G. PAUWELS ◽  
ROMAN A. NAZAROV ◽  
VLADIMIR V. BOBROV ◽  
NIKOLAY A. POYARKOV
Keyword(s):  
New Species ◽  
National Park ◽  
Species Complex ◽  
Nature Reserve ◽  
Taxonomic Status ◽  
Southern Vietnam ◽  
Number Of Species ◽  
Two Populations ◽  
A New Species

Based on genetic, morphological and chromatical comparisons we evaluate the taxonomic status of two southern Vietnamese forest-dwelling populations of the Cyrtodactylus irregularis species complex. We confirm the allocation of the population from Binh Chau—Phuoc Buu Nature Reserve (Ba Ria—Vung Tau Province) to C. cattienensis and we describe the population of Nui Chua National Park (Ninh Thuan Province) as Cyrtodactylus sangi sp. nov. This brings to 18 the number of species within the C. irregularis complex and to 41 the number of described Cyrtodactylus species recorded from Vietnam. 

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