The state of systematics of North American Baetis Leach, 1815 (Ephemeroptera: Baetidae), with recommendations for identification of larvae

Zootaxa ◽  
2018 ◽  
Vol 4394 (1) ◽  
pp. 105 ◽  
Author(s):  
J.M. WEBB ◽  
LUKE M. JACOBUS ◽  
S.P. SULLIVAN

The North American species of Baetis Leach (Ephemeroptera: Baetidae) are reviewed. Nearly one-third of species are either unknown or inadequately described in the larval stage, a fact not reflected in most keys or standard taxonomic efforts for bioassessment, which typically recommend species-level identifications of larvae. Furthermore, our new observations indicate that some previously published stage associations should be viewed as only tentative, and molecular evidence suggests that current species taxonomy does not reflect biological species. In order to acknowledge these deficiencies, but at the same time provide a degree of higher taxonomic resolution beyond the genus level, we recommend a scheme for identifications incorporating previously established species groups and the species complexes and species included within them. Species complexes are proposed for instances when there are either multiple species that cannot be differentiated in the larval stage or when multiple lines of evidence indicate more than one actual species is included in a single species concept. Complexes include B. flavistriga complex (B. flavistriga McDunnough + B. phoebus McDunnough + B. rusticans McDunnough), B. intercalaris complex (B. intercalaris McDunnough), B. vernus complex (B. brunneicolor McDunnough + B. vernus Curtis), B. bicaudatus complex (B. bicaudatus Dodds), B. tricaudatus complex (B. tricaudatus Dodds), and B. piscatoris complex (B. piscatoris Traver + B. palisadi Mayo + B. persecutus McDunnough [=B. persecutor McCafferty n. obj. syn]). A new larval identification key incorporating the B. piscatoris complex is provided. 

Zootaxa ◽  
2012 ◽  
Vol 3271 (1) ◽  
pp. 1 ◽  
Author(s):  
CONRAD J. HOSKIN

In Australia the frog family Microhylidae is largely restricted to tropical rainforests of the Wet Tropics region in the north-east of the country, but in that region the family is diverse. Only one species, Cophixalus ornatus, is widespread in the WetTropics but there has been suspicion that it may comprise multiple species. A recent study (Hoskin et al. 2011) assessedgenetic and phenotypic variation across the range of C. ornatus, finding three deeply divergent genetic lineages that differin mating call and some aspects of morphology. Two of these lineages abutt in the central Wet Tropics and in that areahybridization was found to be very limited despite sympatry at high densities. Based on multiple lines of data, Hoskin etal. (2011) concluded that the three genetic lineages represent biological species. The taxonomy of these three lineages isresolved here. I describe two new species, Cophixalus australis sp. nov. and Cophixalus hinchinbrookensis sp. nov., andredescribe C. ornatus. The three species are not distinguishable based on any single morphological or call trait and arebest identified by genetics or locality. The distributions of the three species are largely allopatric. Cophixalus ornatus isfound in rainforest in the northern Wet Tropics, C. australis sp. nov. occurs in rainforest and adjacent wet sclerophyllforests in the central and southern Wet Tropics, and C. hinchinbrookensis sp. nov. inhabits rainforest and montane heathon Hinchinbrook Island. All three species are common. Cophixalus australis sp. nov. contains three genetic subgroupsthat are considered a single species based on phenotypic similarity and high levels of hybridization at contact zones. Thedescription of Cophixalus australis sp. nov. and Cophixalus hinchinbrookensis sp. nov. brings the number of Australian Cophixalus species to 18, 15 of which are restricted to the Wet Tropics region.


Zootaxa ◽  
2019 ◽  
Vol 4615 (2) ◽  
pp. 285
Author(s):  
DANIEL REYNOSO-VELASCO ◽  
ROBERT W. SITES

The genus Ambrysus Stål is the most species rich genus of Naucoridae. Multiple species groups in the genus have been proposed, including the North American Ambrysus signoreti Stål complex. Four new species belonging to the A. signoreti complex are described and illustrated: three from Mexico (Ambrysus brailovskyi Reynoso & Sites n. sp., A. henryi Reynoso & Sites n. sp., A. schuhi Reynoso & Sites n. sp.) and one from Mexico and Guatemala (A. sitesi Reynoso n. sp.), bringing the total number of described species of Ambrysus to 97. 


1991 ◽  
Vol 123 (S154) ◽  
pp. 3-104 ◽  
Author(s):  
Darren A. Pollock

AbstractThe classification of the nine world species of Pytho Latreille is reviewed by study of adult, larval, and pupal stages. Keys are provided for separation of species in these three life stages. Taxonomic changes (senior synonym in brackets) include synonymy of P. fallax Seidlitz 1916 [= P. niger Kirby 1837]; P. americanus Kirby 1837 [= P. planus (Olivier 1795)]; P. deplanatus Mannerheim 1843 is transferred from a junior subjective synonym of P. depressus (Linnaeus 1767) to a junior subjective synonym of P. planus (Olivier 1795). Lectotype designations are provided for the following: P. seidlitzi Blair 1925; P. nivalis Lewis 1888; P. niger Kirby 1837; P. fallax Seidlitz 1916; P. abieticola J. Sahlberg 1875; and P. americanus Kirby 1837. Eight larval stage, and 12 adult stage characters were selected for cladistic analysis. Lacking out-group material, pupal characters were not analysed. Character states were polarized using a generalized out-group composed of the three other genera of Pythinae (all monobasic). Phylogenetic analysis based on these 18 characters suggests four monophyletic species-groups: P. seidlitzi group (P. seidlitzi Blair — North America); P. kolwensis group (P. strictus LeConte – North America, P. kolwensis C. Sahlberg —Fennoscandia and the U.S.S.R., P. nivalis Lewis — Japan); P. niger group (P. niger Kirby — North America, P. abieticola J. Sahlberg — Europe, P. jezoensis Kôno — Japan); P. depressus group [P. planus (Olivier, 1795) — North America, P. depressus (Linnaeus, 1767) — Europe and the U.S.S.R.]. Larval stage synapomorphies are relatively more important in defining the species-groups than are those of the adult stage. The ancestor of Pythidae may have been associated with Coniferae as early as the Jurassic. The common ancestor of Northern Hemisphere Pythinae became isolated upon Laurasia once separation from Gondwanaland occurred near the end of the Jurassic. Two of the species-groups have similar disjunctions in North America, Europe, and Japan. The relatively eastern distributions of the North American member of each suggests that the ancestor of each species-group was Euramerican, and underwent vicariance with the opening of the North Atlantic in the Middle Cretaceous. The present distribution of both species-groups is thought to have been caused by the same vicariant event. The ancestor of the P. depressus group, which is presently circumboreal, was probably widespread and could have been Asiamerican in distribution. In the middle to late Tertiary, evidence suggests that Beringia was covered with coniferous forest, and the ancestor of the P. depressus group probably extended across this land bridge. Final separation between any North American and European/Asian species occurred in the Late Miocene or Pliocene, when a cooling climate made possible the evolution of treeless tundra in the north.


Zootaxa ◽  
2021 ◽  
Vol 5005 (3) ◽  
pp. 304-316
Author(s):  
DANIEL REYNOSO-VELASCO

The genus Ambrysus Stål is a species-rich genus in which multiple species groups have been proposed, including the North American Ambrysus signoreti Stål complex. The new Mexican species Ambrysus altiplanus Reynoso n. sp., which belongs to the A. signoreti complex, is described and illustrated, bringing the total number of described species of Ambrysus to 67. Also, new state records are reported for three species of the same complex, two of which are endemic to Mexico.


Zootaxa ◽  
2019 ◽  
Vol 4691 (2) ◽  
pp. 125-138 ◽  
Author(s):  
NIKOLAI M. KOROVCHINSKY1 ◽  
SHELLEY E. ARNOTT

The invasive species of the genus Bythotrephes introduced in the North American lakes in 1970s-early 1980s was named variously either B. cederstroemi or B. longimanus. The investigation of individuals of the genus from 15 Canadian lakes has allowed us to identify all of them as B. cederströmii Schödler, based on the detailed taxonomic redescription of the Eurasian representatives of the species. The available documented data (figures and photographs) on Bythotrephes from other North American lakes, made it possible to recognize their identity with this species as well. The possible introduction of interspecific hybrids of the genus Bythotrephes in the North American lakes has not been confirmed. 


1959 ◽  
Vol 91 (S10) ◽  
pp. 5-338 ◽  
Author(s):  
Margaret Rae MacKay

AbstractThe late-instar larvae of about 185 species of the North American Olethreutidae are described and most of them illustrated. Included in these are many pests, such as Grapholitha molesta, Carpocapsa pomonella, and Spilonota ocellana on fruit trees, Paralobesia viteana on grapes, Ancylis comptana fragariae on strawberries, Laspeyresia nigricana in pea pods, Laspeyresia caryana in hickory and pecan nuts, Taniva albolineana in spruce needles, and species of Rhyacionia and Petrova on pines. Keys to species groups and to individual species are provided. Of the diagnostic and specialized characters listed, the most useful include the setae, the spinneret, and the shape of the larva, especially of its head and anal shield. The main characters are given for the postulated ancestral larva and for the highly developed larva. Most of the species groups are arranged according to the suggested phylogenetic relationship of their larvae, emphasizing the necessity of a revision of the family. Larvae of some genera previously difficult to classify, such as Pseudogalleria and Hystricophora, indicate the relationship of those genera to other groups; conversely, lack of relationship is clearly shown in other instances, e.g., between Carpocapsa pomonella and Carpocapsa saltitans, and between the two species Epiblema culminana and E. suffusana and other members of the genus Epiblema.


1977 ◽  
Vol 109 (7) ◽  
pp. 907-930 ◽  
Author(s):  
C. M. Yoshimoto

AbstractThe name Enaysma Delucchi, 1954 is synonymized with the name Achrysocharoides Girault, 1913. Achrysocharoides is divided into two species-groups, guizoti and gahani. Fifteen North American species are recognized, including five that are new: A. reticulatus, A. bisulcus, A. albus, A. tetrapunctatus, and A. intricatus. A key to species, host lists, and distributions are included.


1978 ◽  
Vol 15 (9) ◽  
pp. 1422-1436 ◽  
Author(s):  
L. F. Jansa ◽  
B. Mamet ◽  
A. Roux

Three short cores of Windsor Group carbonates from the northeast Newfoundland Shelf yielded Late Viséan foraminifers of Zones 15 and 16Inf. This most northeastward occurrence of the marine Lower Carboniferous on the American continent has foraminifers identical to those reported from Windsor carbonates exposed in southwestern Newfoundland and Nova Scotia. The foraminifera belong to the North American realm and not to the Tethyan realm. The algae are exceptionally well preserved. Except for a single species, they are also 'American' and not Tethyan. This confirms that the proto-Atlantic effectively separates the North American and Euro–African continental blocks in Early Carboniferous time.


2019 ◽  
Author(s):  
Herakles Antonio Garcia ◽  
Alexander P. Blanco ◽  
Adriana C. Rodrigues ◽  
Carla M. Rodrigues ◽  
Carmen S. A. Takata ◽  
...  

Abstract Background: The subgenus Megatrypanum comprises trypanosomes of cervids and bovids from around the world. Here, Odocoileus virginianus (white-tailed deer = WTD) and its ectoparasite, the deer ked Lipoptena mazamae (hippoboscid fly), were surveyed for trypanosomes in Venezuela. Results: Haemoculturing unveiled 20% infected WTD, while 47% (7/15) of blood samples and 38% (11/29) of ked guts tested positive for the Megatrypanum-specific TthCATL-PCR. CATL and SSU rRNA sequences uncovered a single species of trypanosome. Phylogeny based on SSU rRNA and gGAPDH sequences tightly cluster WTD trypanosomes from Venezuela and the USA, which were strongly supported as geographical variants of the herein described Trypanosoma (Megatrypanum) perronei sp. n. In our analyses, T. perronei was closest to T. sp. D30 of fallow deer (Germany), both nested into TthII alongside other trypanosomes of cervids (North American elks and European fallow, red and sika deer), and bovids (cattle, antelopes and sheep). Insights into T. perronei life cycle were obtained from early haemocultures of deer blood and co-culture with mammalian and insect cells showing flagellates resembling Megatrypanum trypanosomes previously reported in deer blood, and deer ked guts. For the first time, a trypanosome from a cervid was cultured and phylogenetically and morphologically (light and electron microscopy) characterised. Conclusions: In the analyses based on SSU rRNA, gGAPDH, CATL and ITS rDNA sequences, neither cervids nor bovids trypanosomes were monophyletic but intertwined within TthI and TthII major phylogenetic lineages. One host species can harbour more than one species/genotype of trypanosomes, but each trypanosome species/genotype was found in a single host species or in phylogenetically related hosts. Molecular evidence that L. mazamae may transmit T. perronei suggests important evolutionary constraints making tight the tripartite T. perronei–WTD–deer ked association. In a plausible evolutionary scenario, T. perronei entered South America with North American WTD at the Pliocene–Pleistocene boundary following the closure of the Panama Isthmus.


2021 ◽  
Vol 2118 (1) ◽  
pp. 012011
Author(s):  
D A Zuluaga ◽  
D Sabogal ◽  
C A Buenaventura ◽  
C J Slebi

Abstract The physical response and geotechnical properties of diatomaceous soils are not fully understood, data are sparse, and do not account for the effects of single and multispecies frustule content, origin, type, and variability. The main physical problem lies in the irregular response of diatomaceous soils due to micro and nano scale causes and its unexpected effects on the macro scale. This research compared the characteristics of a multispecies diatomaceous soil sample (North American origin) with other diatomaceous single-species soils. Six artificial soil mixtures were prepared, dosed by weight, in order to determine the influence of the content of frustules. The results show that the liquid limit of the samples is lower than that of the monospecies samples for any content of frustules. The pore areas of the monospecies samples are found to be 4 to 7 times larger than those of the North American soil. Void ratios and compressibility ranges are higher as the diatom content increases. The internal friction angle of diatomaceous soils varies in a non-linear tendency with respect to fossil content. For the studied soil at 100% fossil concentration, the internal friction angle reached 38.32°, a magnitude that is lower than the values reported for most of the monospecies contrast samples.


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