Tracking the movement of Nesidiocoris tenuis among banker plants and crops in a tomato greenhouse by DNA markers of host plants

The zoophytophagous predator, Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae), is an important biological control agent. To maintain this insect, several non-crop host plants are used as banker plants in greenhouse crop systems. To optimize the efficiency of the predator-banker plant interaction, it is necessary to investigate how individual predators move between banker plants and crops. However, the movement is difficult to quantify under field conditions. Therefore, we investigated the movement of N. tenuis between tomato plants (Solanum lycopersicum L., Solanales: Solanaceae) and three banker plants (Cleome hassleriana Chod., Brassicales: Cleomaceae; Sesamum indicum L., Lamiales: Pedaliaceae; and Verbena × hybrida Voss, Lamiales: Verbenaceae) in a greenhouse by conducting PCR using plant-species-specific primers. Laboratory analysis results showed that our molecular method could detect N. tenuis activity within a relatively short time (≤ 24 h). In addition, N. tenuis predation on a pest species was unlikely to result in false detection of plant DNA in the pest (suggesting that N. tenuis had been on the plants). Multiple plant species were detected in adult insects collected from the greenhouse plants, indicating that N. tenuis frequently moved across the mentioned plant species. The movement patterns of N. tenuis between plant species varied substantially based on the plant species from which they were collected, which suggested each of the plant species had different functions for N. tenuis. Our findings revealed that planting multiple host plants would stabilize the N. tenuis population in biological control programs.

     

Contrasting patterns of population structure in the montane caddisflies Hydropsyche tenuis and Drusus discolor in the Central European highlands

1. In this study, we compared mitochondrial sequence data (cytochrome oxidase I) to infer the population structure of the two montane caddisflies Hydropsyche tenuis and Drusus discolor. The two species are contrasting examples of montane aquatic insects with insular distributions: D. discolor is restricted to altitudes above 600 m, H. tenuis is limited to the same mountain ranges in Central Europe but inhabits lower altitudes. 2. In particular, we ask whether these two species with similar regional distributions show similar patterns of population structure and haplotype diversity, and whether any differences can be attributed to population history and/or autecology. 3. To determine the population structure of both species, we applied conventional population genetics analyses to mitochondrial sequence data. We collected and sampled 121 specimens of H. tenuis from 29 sites in 10 different regions of the Central European highlands and 138 individuals of D. discolor from 40 sites in 11 different regions. 4. Nine unique haplotypes were identified for H. tenuis and 34 for D. discolor. There were eight variable positions in H. tenuis and 41 in D. discolor. The maximum difference between haplotypes was 0.8% (4 bp) for H. tenuis and 4.2% (21 bp) for D. discolor. We observed haplotype overlap between geographic regions for both species. Analysis of molecular variance showed that two‐thirds of the total variance in H. tenuis was found among regions while in D. discolor, a larger portion of variance was found within regions and populations due to a higher number of haplotypes observed within regions. Mantel test showed a significant relationship between genetic and geographic distance in D. discolor, but no significant relationship in H. tenuis. 5. Our analyses show that, despite their very similar overall distribution pattern in Europe, the two species exhibit distinct population structures, which may reflect differences in phylogeographic history, dispersal capabilities, habitat specifity or within‐region geographic occurrence.     

Predation of a biological control agent,Nesidiocoris tenuis (Hemiptera: Miridae), by the spider Leucauge blanda in greenhouse eggplant crops

Nesidiocoris tenuis (Hemiptera: Miridae) is used widely around the world as a biological control agent. In Kochi Prefecture, Japan, at the end of each greenhouse eggplant crop production period, the N. tenuis populations that have developed are collected and transferred to ‘natural-enemy-rearing greenhouses’ so that farmers can use the bug in the next production period. However, spider numbers have been increasing at the end of the production periods and it is becoming difficult to collect N. tenuis in some greenhouses. Therefore, we constructed specific primers for N. tenuis mtDNA to test whether the species was being preyed upon by the predominant spider species, Leucauge blanda. In polymerase chain reactions, these primers amplified a 148-bp fragment of the mitochondrial cytochrome oxidase subunit I gene of N. tenuis but not of any of the 13 other arthropod species tested that occurred in eggplant greenhouses. In a laboratory experiment, the rates of detection of N. tenuis DNA in the spiders after the end of a period of feeding on the bug were 90% at 0?h, 60% at 24?h, and 0% at 72?h. In a greenhouse field experiment, the rate of detection of N. tenuis DNA in the spider was 95%. These results suggest that L. blanda is responsible for the observed suppression of N. tenuis populations in greenhouse eggplant crops.     

Intraguild predation and cannibalism among Dicyphini: Dicyphus cerastii vs. two commercialized species

Dicyphine mirids are one of the most important groups of predators on tomato. In the Mediterranean region, several species in the genera Dicyphus, Macrolophus, and Nesidiocoris (Hemiptera: Miridae, Bryocorinae, Dicyphini) colonize protected horticultural crops. In Portugal, Nesidiocoris tenuis (Reuter) is increasingly abundant in the mirid species complex of tomato crops and appears to be displacing the native Dicyphus cerastii Wagner. In order to know whether intraguild predation (IGP) can explain the decreasing abundance of D. cerastii, we evaluated predatory interactions between adult females and first instars of D. cerastii vs. N. tenuis but also D. cerastii vs. Macrolophus pygmaeus (Rambur), as this species is also naturally present in horticultural crops in Portugal. Cannibalistic interactions were also tested for the same three species. All experiments were performed under laboratory conditions, in Petri dish arenas, in the presence or absence of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) eggs as alternative prey. Predation on both heterospecific and conspecific nymphs occurred only in the absence of alternative food. Intraguild predation was mutual and symmetrical between D. cerastii and M. pygmaeus. However, IGP was asymmetrical between D. cerastii and N. tenuis, favouring the first. Cannibalism was not significantly different among these mirid species. Our results show that D. cerastii has a greater capacity to feed on intraguild prey than N. tenuis. Therefore, IGP on small nymphs does not explain the abundance shift between D. cerastii and N. tenuis.     

Effects of an alternative diet of Artemia cysts on the development and reproduction of Nesidiocoris tenuis (Hemiptera: Miridae)

The small green mirid Nesidiocoris tenuis Reuter (Hemiptera: Miridae) preys on pest insects such as whiteflies and serves as a biological control agent in many greenhouses. However, this mirid is limited in its application, because individuals tend to escape from agricultural fields and soon die due to a lack of available food sources. In addition, the food traditionally used to culture N. tenuis is expensive. Thus, identifying low-cost foods for N. tenuis would help to increase the species’ further utilization. Brine shrimp (Artemia spp., Anostraca: Artemiidae) cysts are potentially useful as a low-cost alternative diet to sustain populations of predatory natural enemies. We evaluated the developmental and reproductive performance of N. tenuis when reared on Artemia salina L. cysts supplied in dry or wet form. The dry cysts showed a similar performance to that of Mediterranean flour moth (Ephestia kuehniella Zeller, Lepidoptera: Pyralidae) eggs, which are often used as a nutritional diet for mass rearing of N. tenuis. Although the wet cysts contributed to growth, compared to other diets, they were inferior in nymphal development time and longevity. These results suggest that relatively inexpensive Artemia dry cysts can be used to successfully breed N. tenuis and sustain populations in crop fields.

     

The occurrence of shell-boring Phaeophila species in Britain

Phaeophila tenuis (Kylin) R. Nielsen (= Entocladia tenuis Kylin) is reported for the first time from British shores. The existence in Britain of a form intermediate in morphology between P. tenuis and Phaeophila engleri Reinke is also noted. The relationships of this form and P. tenuis to each other and to Phaeophila dendroides (Crouan frat.) Batt. are discussed with reference to the effect of host-shell species and habitat on morphology.     

Intraguild predation and competitive displacement between Nesidiocoris tenuis and Dicyphus maroccanus,two biological control agents in tomato pests

Dicyphus maroccanus Wagner and Nesidiocoris tenuis Reuter (Hemiptera: Miridae) are 2 biological control agents in tomatoes. Through the crop seasons, a natural shift in the occurrence of both mirids in favor of N. tenuis has been observed at the end of the cropping cycle in eastern Spain. To better optimize their conservation, the reasons for the observed change, such as intraguild interactions (IGP) or the influence of environmental conditions, are worth elucidating. To do this, we first studied the IGP of adult females on heterospecific nymphs in the laboratory. We next studied exploitative competition between adults and nymphs of each species when feeding on Ephestia kueniella Zeller (Lepidoptera: Pyralidae) eggs in the laboratory. Finally, to analyze the competitive displacement between both mirids, we conducted a semifield experiment in which both predators were released together. All experiments were conducted at 2 temperature regimes (20 and 25°C). Adult‐to‐nymph intraguild interactions occurred only at 25 ºC at very low levels, showing that N. tenuis attacked and consumed a greater proportion of heterospecific nymphs. Nesidiocoris tenuis was a better competitor than D. maroccanus when feeding on the shared prey in the presence of its heterospecific nymph at 25 ºC. In semifield conditions, N. tenuis showed a competitive advantage over D. maroccanus at both temperatures. We conclude that there is not direct interference between both species, however, N. tenuis has a greater ability to outcompete, since it is best adapted to higher temperatures and it is able to remove food sources for D. maroccanus.     

Facilitative effect of Lotustenuis on Paspalumdilatatum in a lowland grassland of Argentina

We studied the responses in growth and N content of the perennial grass Paspalum dilatatum to the substitution of Lotus tenuis for a whole group of species, the dicotyledons of a natural grassland community, in the Salado lowland Pampas of Argentina. Two kinds of manipulations were performed in the field: removal of alien dicots with herbicide application, and introduction of L. tenuis, resulting in a combination of four treatments, arranged in a 2 × 2 factorial randomized block design. Leaf area per tiller of P. dilatatum was higher when it was growing near L. tenuis; this increase was the result of a greater leaf elongation rate and slower leaf senescence. In the vicinity of L. tenuis, P. dilatatum exhibited an increase in tiller production and a decrease in tiller death. More tillers were functional at the end of the growing season and their aboveground biomass was 5␣times higher than for plants growing in plots where the community dicots were removed. This increment was accompanied by a higher N content. Growth enhancement of P. dilatatum plants when L. tenuis was the␣immediate neighbour is interpreted as the result of facilitation mediated by higher N availability, and not as a consequence of a release from competition exerted by the community dicots. Competition and facilitation did not interact to produce an increase in the vegetative output of Paspalum dilatatum plants growing under these field conditions. It is on these grounds that Lotus tenuis might be considered as a keystone species in the managed grassland. Received: 5 July 1997 / Accepted: 12 December 1997     

Bryozoa from northern Red Sea,Egypt: 1 Crisia (Cyclostomata)

Seventy-five bryozoan species were picked from shallow bottom sediments (0–33 m depths) at five sites in the northern Red Sea: El Fanader, Hurghada Harbour, Makkadi Bay, Al Qweh Lagoon and El-Humrawen. Crisia specimens (Cyclostomata) are common and exhibit different variations. Six species were recognised among the specimens collected: Crisia eburnea (Linnaeus), Crisia elongata (Milne-Edwards), Crisia hornesi Reuss, Crisia sertularoides (Audouin), Crisia tenuis MacGillivray and Crisia hurghadaensis n. sp. The present paper deals with these Crisia species; other bryozoan taxa recovered will be published later. Biogeographic study reveals that three of these species are cosmopolitan, and represented by common to abundant occurrences (C. elongata, C. eburnea and C. hornesi). Two species are local endemics, and represented by only rare occurrences (C. sertularoides and C. hurghadaensis n. sp.). One species (C. tenuis) is Indo-Pacific, and is recorded here for the first time in equatorial waters.     

Predation by <Emphasis Type="Italic">Nesidiocoris tenuis</Emphasis> on <Emphasis Type="Italic">Bemisia tabaci</Emphasis> and injury to tomato

Tomato is the most important vegetable crop in Spain. The mirid bug Nesidiocoris tenuis (Reuter) commonly appears in large numbers in protected and open-air tomato crops where little or no broad-spectrum insecticides are used. Nesidiocoris tenuis is known to be a predator of whiteflies, thrips and several other pest species. However, it is also considered a pest because it can feed on tomato plants, causing necrotic rings on stems and flowers and punctures in fruits. Our objectives were to evaluate predation by N. tenuis on sweetpotato whitefly Bemisia tabaci Gennadius under greenhouse conditions and establish its relationship to N. tenuis feeding on tomato. Two different release rates of N. tenuis were compared with an untreated control (0, 1 and 4 N. tenuis plant⁻¹) in cages of 8 m². Significant reductions of greater than 90% of the whitefly population and correspondingly high numbers of N. tenuis were observed with both release rates. Regression analysis showed that necrotic rings on foliage caused by N. tenuis were best explained by the ratio of B. tabaci nymphs:N. tenuis as predicted by the equation y = 15.086x − 0.6359.

Zoophytophagy in the plantbug Nesidiocoris tenuis

1 The zoophytophagy of Nesidiocoris tenuis (Reuter) (Heteroptera: Miridae) was characterized in relation to prey availability and environmental factors by: (i) monitoring its population dynamics in tomato greenhouses; (ii) analysis of the influence of N. tenuis and whitefly density, temperature and humidity on the intensity of N. tenuis plant feeding; and (iii) laboratory assays under controlled conditions to determine the intensity of plant feeding in relation to prey availability, temperature and humidity. 2 A negative relationship was found between plant feeding and predated whiteflies in tomato greenhouses. Plant feeding was directly related to N. tenuis density and temperature and inversely related to whitefly density. The significance of prey availability and temperature was corroborated in laboratory assays. The intensification of plant feeding at low prey density indicates switching from zoophagy to phytophagy as prey become scarce. 3 Nesidiocoris tenuis showed a typical predator dynamic in relation to variance in prey density. Populations increased after whitefly outbreaks and decreased after whitefly had been depleted. The rapid decrease of N. tenuis populations after whitefly decreased, however, suggests that plants are a poorer nutrient source than whitefly for this species.     

Suction among pickers: jaw mechanics,dietary breadth and feeding behaviour in beach‐spawning Leuresthes spp. compared with their relatives

Jaw mechanics and dietary breadth in California grunion Leuresthes tenuis and Gulf grunion Leuresthes sardina were compared with three other members of the tribe Atherinopsini to test whether these two species have evolved a novel jaw protrusion that might be associated with feeding narrowly on abundant prey near spawning beaches. Quantitative comparison of cleared‐and‐stained specimens of five members of the atherinopsine clade showed that, compared with false grunion Colpichthys regis, topsmelt Atherinops affinis and jacksmelt Atherinopsis californiensis, L. tenuis and L. sardina have longer, more downwardly directed premaxillary protrusion, expanded dentary and premaxillary bones, greater lower jaw rotation and larger premaxilla–vomer separation. Leuresthes tenuis showed greater differences than L. sardina in these features. Comparison of the gut contents of L. tenuis and A. affinis with zooplankton samples collected simultaneously with these fishes in the water column within 1 km of shore showed that, as predicted, L. tenuis fed predominantly on mysid crustaceans and had a narrower diet than A. affinis. High‐speed video analysis showed that L. tenuis exhibits a mean time to maximum jaw protrusion c. 2·5 times shorter than that of A. affinis. The grunion sister species, especially L. tenuis, have evolved suction feeding that may allow efficient feeding on common, evasive prey near spawning sites. The morphological traits seen in both species of Leuresthes signify a marked difference from their closest relatives in prey capture and suggest a type of jaw protrusion not yet seen in cyprinodontiforms or perciforms.     

Dynamics of root growth and decay in two grasses native to semi-arid Argentina

The pattern of root growth and decay in Stipa tenuis Phil, and Piptochaetium napostaense (Speg.) Hack, was examined under field conditions in root observation chambers. The roots of both species grew uninterruptedly throughout the whole year. Root elongation during spring, summer, and early autumn can be six and five times as high as that in the late autumn to winter period for S. tenuis and P. napostaense, respectively. Root decay was a continuous process in both species throughout the year, with maximum decay rates occurring from late spring through to the middle of autumn. Comparison of minimum and maximum values registered during the year showed a root decay ratio of about 4:1 for S. tenuis and one of 5:1 for P. napostaense. During the period of maximum root growth, both species showed a pulse-like pattern of root elongation in response to rapid changes in water availability. In a semi-arid region in which the soil is notably shallow, root growth behaviour of this kind should allow these species to respond opportunistically to water.     

Density thresholds for Nesidiocoris tenuis (Heteroptera: Miridae) in tomato crops

Nesidiocoris tenuis (Reuter) (Heteroptera: Miridae) is common in vegetable crops of the Mediterranean area, with an increasing worldwide range of geographical distribution. This omnivore is a reputed predator of small arthropod pests, but also produces injuries on vegetative and reproductive plant parts. The aim was to estimate density thresholds based on N. tenuis and whitefly abundance for the management of N. tenuis in tomato crops. The assay was carried out in mesh-walled and plastic greenhouses in southern Spain during 2004 and 2007. The natural population dynamics of N. tenuis and whitefly were monitored, and impact on yield quantified. The economic injury level and intervention threshold were predicted based on the zoophytophagous response of N. tenuis and the yield compensation of tomato plants. The proportion of aborted flowers on the tomato plants was related directly to the abundance of N. tenuis and inversely to the interaction between the number of N. tenuis and the number of whitefly immatures. Over-compensation of fruit weight was predicted for flower abortion rates due to N. tenuis lower than 0.171. No yield reduction is expected for values <0.65 N. tenuis per leaf, independent of the whitefly abundance, nor for up to 5 N. tenuis and >26 whitefly immatures per leaf. For intermediate N. tenuis levels, the outcome depends on the prey density. The probability of N. tenuis producing yield loss in tomato crops increases at N. tenuis:whitefly ratios >0.168. Yield reduction is expected after N. tenuis population peaks, when whitefly numbers have been reduced.     

Phosphate-solubilization mechanism and in vitro plant growth promotion activity mediated by Pantoea eucalypti isolated from Lotus tenuis rhizosphere in the Salado River Basin (Argentina)

Aims: To isolate and characterize phosphate‐solubilizing strains from a constrained environment such as the Salado River Basin and to assess their phosphate‐solubilizing mechanisms, to further selection of the most promising strains to inoculate and improve the implantation and persistence of Lotus tenuis in the most important area devoted to meat‐cow production in Argentina. Methods and Results: Fifty isolates were obtained and through BOX‐PCR analysis, 17 non‐redundant strains were identified. Subsequently, they were found to be related to Pantoea, Erwinia, Pseudomonas, Rhizobium and Enterobacter genera, via 16S rRNA gene sequence analysis. This was in agreement with the clusters obtained by antibiotic resistance analysis. All isolates were tested for their phosphate‐solubilizing activity and selected strains were inoculated onto L. tenuis plants. The most efficient isolate, was identified as Pantoea eucalypti, a novel species in terms of plant growth‐promoting rhizobacteria. Conclusions: The isolates obtained in this study showed a significant in vitro plant‐growth promoting activity onto Lotus tenuis and the best of them solubilizes phosphate mainly via induction of the metabolism through secretion and oxidation of gluconic acid. Singnificance and Impact of the Study: The use of these bacteria as bioinoculants, alone or in combination with nitrogen‐fixing micro‐organisms, could be a sustainable practice to facilitate the nutrient supply to Lotus tenuis plants and preventing negative side‐effects such as eutrophication.     

Preplant release of Nesidiocoris tenuis and supplementary tactics for control of Tuta absoluta and Bemisa tabaci in greenhouse tomato

An early release system developed for Nesidiocoris tenuis Reuter (Heteroptera: Miridae) could provide a good control of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in tomato. Tuta absoluta and the whitefly Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) often appear simultaneously in tomato crops and this might affect control capacity. Therefore, the new approach needs to be tested in a situation with both pests present. In addition, Bacillus thuringiensis Berliner and Trichogramma achaeae Nagaraja & Nagarkatti (Hymenoptera: Trichogrammatidae) have been shown to be effective against T. absoluta and could be a supplement to N. tenuis. Two experiments were carried out to evaluate the potential of this approach and its combination with supplementary control agents against T. absoluta. In the first experiment four treatments were compared (T. absoluta, B. tabaci, T. absoluta + N. tenuis, and T. absoluta + B. tabaci + N. tenuis) and N. tenuis was able to control T. absoluta and B. tabaci either alone or together. In the second experiment, five treatments were compared: T. absoluta, T. absoluta + N. tenuis, T. absoluta + N. tenuis + T. achaeae, T. absoluta + N. tenuis + B. thuringiensis, and T. absoluta + N. tenuis + T. achaeae + B. thuringiensis. Nesidiocoris tenuis again proved capable of significantly reducing T. absoluta populations, and the implementation of additional agents did not increase its effectiveness.     

May Rare Metallophytes Benefit from Disturbed Soils Following Mining Activity? The Case of the Crepidorhopalon tenuis in Katanga (D. R. Congo)

Cuprophytes are plants that mostly occur on Cu‐rich soil. In South Central Africa, these species are threatened by intensive mining exploitation destroying their habitats. Crepidorhopalon tenuis (Scrophulariaceae) is a tiny annual cuprophyte endemic to the Zambesian center of endemism and is particularly abundant in the Lubumbashi area. We investigate here the ecological niche of C. tenuis through the analyses of its abundance and distribution in relation to soil factors, plant community composition, and anthropogenic perturbations. Soil and vegetation data were collected in seven sites (five metalliferous and two nonmetalliferous). The current study shows that C. tenuis has its ecological optimum on copper‐rich soil and can be referred to as an elective pseudometallophyte. This species is rare in primary steppic savanna on natural metalliferous soil. Its frequency and abundance peak in pioneer communities on bare soil. In particular, the species showed a surprising ecological plasticity as it was able to benefit from anthropogenic disturbance and to colonize the large areas of bare, contaminated soil left over by mining activities. Our results strongly suggest that C. tenuis was a very rare species in natural metalliferous communities, restricted to patchy areas of open soil in steppic savanna. Recent anthropogenic habitats may have conservation value for some rare metallophytes with colonizing traits and low competitive ability.     

PCR gut analysis reveals that Tenuiphantes tenuis (Araneae: Linyphiidae) is a potentially significant predator of Argentine stem weevil,Listronotus bonariensis (Coleoptera: Curculionidae), in New Zealand pastures

Polymerase chain reaction (PCR) gut analysis was conducted on specimens of the introduced spider Tenuiphantes tenuis collected from dairy pasture in Canterbury, New Zealand. PCR primers were specifically designed to amplify a fragment of the mitochondrial gene cytochrome c oxidase subunit 1 (COI) from Listronotus bonariensis and revealed that this major pasture pest species is consumed in the field by T. tenuis. The field predation rate of L. bonariensis by T. tenuis was estimated from our PCR results together with published data on the degradation of DNA and the density of T. tenuis in Canterbury pastures. We found that T. tenuis is a potentially significant predator of L. bonariensis in New Zealand pastures.     

CYTOTAXONOMY OF THE ELEOCHARIS TENUIS COMPLEX

Chromosome numbers of 2n = 20, 24, 36, and 38 were found in the various taxa comprising the Eleocharis tenuis complex in the United States. Eleocharis tenuis var. verrucosa, the only taxon in the complex with 2n = 20 is given the new status of a full species [E. verrucosa (Svens.) Harms] and seems most closely allied to two southern members of the subseries Truncatae which are not members of the tenuis complex s. s. Karyotypes and meiotic pairing in artificial hybrids indicate that the remainder of the taxa are derivatives of X = 6 with E. tenuis and one of two cytotypes of E. compressa with the lowest numbers of 2n = 24, although evidence is presented to indicate that they are of amphidiploid origin. A second cytotype of E. compressa with 2n = 36 is a segmental autoallohexaploid, whereas E. elliptica and E. elliptica var. pseudoptera (Svens.) Harms, comb. nov. with 2n = 38 are hyperploid derivatives of 2n = 36.     

Analysis of the complete plastomes of three species of Membranoptera (Ceramiales,Rhodophyta) from Pacific North America

Next generation sequence data were generated and used to assemble the complete plastomes of the holotype of Membranoptera weeksiae, the neotype (designated here) of M. tenuis, and a specimen examined by Kylin in making the new combination M. platyphylla. The three plastomes were similar in gene content and length and showed high gene synteny to Calliarthron, Grateloupia, Sporolithon, and Vertebrata. Sequence variation in the plastome coding regions were 0.89% between M. weeksiae and M. tenuis, 5.14% between M. weeksiae and M. platyphylla, and 5.18% between M. tenuis and M. platyphylla. We were unable to decipher the complete mitogenomes of the three species due to low coverage and structural problems; however, we assembled and analyzed, the cytochrome oxidase I, II, and III loci and found that M. weeksiae and M. tenuis differed in sequence by 1.3%, M. weeksiae and M. platyphylla by 8.4%, and M. tenuis and M. platyphylla by 8.1%. Evaluation of standard marker genes indicated that sequences from the rbcL, RuBisCO spacer, and CO1 genes closely approximated the pair‐wise genetic distances observed between the plastomes of the three species of Membranoptera. A phylogenetic tree based on rbcL sequences showed that M. tenuis and M. weeksiae were sister taxa. Short rbcL sequences were obtained from type specimens of M. dimorpha, M. multiramosa, and M. edentata and confirmed their conspecificity with M. platyphylla. The data support the recognition of three species of Membranoptera occurring south of Alaska: M. platyphylla, M. tenuis, and M. weeksiae.