13 research outputs found
Miocene cyclopid copepod from a saline paleolake in Mojave, California
There are remarkably few direct fossil records of Copepoda, which implies that current estimates of the lineage divergence times and inferences on the historical biogeography remain highly dubious for these small-sized crustaceans. The Cyclopidae, a predominantly freshwater copepod family with 1000+ species and distributed worldwide, has no fossil record at all. Recent collections from the middle Miocene Barstow Formation in Southern California resulted in ample material of finely preserved cyclopid fossils, including both adult and larval stages. To document the antennulary setation pattern in the adult and copepodid instars we used a coding system that is coherent between sexes and developmental stages. The majority of the cyclopid fossils, coming from saline lake environment, represent the modern genus Apocyclops, a euryhaline, thermophilic group occurring both in the New World and Old World. A new species Apocyclops californicus is described, based on the short medial spine and spiny ornamentation of the free segment of leg 5, spinule ornamentation of pediger 5, and well-developed protuberances of the intercoxal sclerite of leg 4. The presence of antennal allobasis and the features of the swimming legs unambiguously place the Miocene Apocyclops in the A. panamensis-clade, a predominantly amphi-Pacific group. The middle Miocene fossils with clear affinities to a subgroup of Apocyclops imply an early Miocene or Paleogene origin of the genus. Based on the geographic patterns of the species richness and morphology in Apocyclops and its presumed closest relative, genus Metacyclops, we hypothesize that: (i) the ancestor of Apocyclops, similar in morphology to some cave-dweller Metacyclops occurring today in the peri-Mediterranean region, might have arrived in North America from Europe via the Thulean North Atlantic bridge in the late Paleoceneâearly Eocene; (ii) Eocene termination of the Thulean land connection might have resulted in the divergence of Apocyclops from the Metacyclops stock
Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences
The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & NemĂ©sio 2007; Donegan 2008, 2009; NemĂ©sio 2009aâb; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported
by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on
18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based
researchers who signed it in the short time span from 20 September to 6 October 2016
Three new species of Mesocyclops G. O. Sars, 1914 (Copepoda, Cyclopoida) from Australia and Burma, with comments on the Mesocyclops fauna of Australia
Three new species of Mesocyclops G. O. Sars, 1914 are described: M. acanthoramus sp. nov. and M. pubiventris sp. nov. from northern Queensland, and M. kayi sp. nov. from northern Burma. Mesocyclops papuensis Van de Velde, 1987 and M. woutersi Van de Velde, 1987 are reported from Australia for the first time. Other Australian records include: M. aspericornis (Daday, 1906) from Queensland; M. brooksi Pesce, De Laurentiis & Humphreys, 1996 from Queensland and Western Australia; M. darwini Dussart & Fernando, 1988 from Queensland and Western Australia; and M. notius Kiefer, 1981 from Queensland and Western Australia. A key to all Australian species of Mesocyclops, as well as a short discussion on the composition and distribution of the Australian fauna, are provided
Redescription and taxonomic notes on Cyclops bohater KoĆșmiĆski, 1933 and Cyclops lacustris G.O. Sars, 1863 (Arthropoda, Crustacea), with an identification key to the Cyclops species of Fenno-Scandinavia
The studies of Cyclops O.F. MĂŒller, 1776 have more than two centuries of tradition in Fenno- Scandinavia, yet, basic taxonomic questions remain unresolved and the limits of the distributional area are very poorly understood in the majority of the taxa (11+) occurring in the region. Based on the types and other materials we redescribe two species, C. lacustris G.O. Sars, 1863 and C. bohater KoĆșmiĆski, 1933, the latter being reported here for the first time from Fenno-Scandinavia; lectotypes of both species have been designated herein. Setulation characters of the antennal coxobasis- and maxillulary palp setae and P1 medial spine, as well as the spine formula of the terminal exopodal segments of the swimming legs (3433) in the adult female distinguish C. lacustris and C. bohater from their congeners. An identification key is provided to the Cyclops species of Fenno-Scandinavia, including information about both the female and male morphology. Although the limited material does not allow us to define the species range limits, our data nevertheless support a Northern European distribution in C. lacustris, and Northern and Central European distribution in C. bohater, while the records from the southern Palearctic need further verification
New diagnostic microcharacters of the cephalothoracic appendages in Cyclops O. F. MĂŒller, 1776 (Crustacea, Copepoda, Cyclopoida)
HoĆyĆska, Maria, Dahms, Hans-Uwe (2004): New diagnostic microcharacters of the cephalothoracic appendages in Cyclops O. F. MĂŒller, 1776 (Crustacea, Copepoda, Cyclopoida). Zoosystema 26 (2): 175-198, DOI: 10.5281/zenodo.540237
Redescription and Relationships of Eucyclops persistens (Copepoda: Cyclopidae) Endemic to the Azov-Black Sea Basin
Taxonomic status of Macaronesian Eucyclops agiloides azorensis (Arthropoda: Crustacea: Copepoda) revisited â morphology suggests a Palearctic origin
Macaronesia, with the exception of the Azores, is one of the few Palearctic provinces where basic taxonomic information on the freshwater copepods is still lacking. We redescribed Eucyclops azorensis, a cyclopid crustacean so far known only in the Azores, and report the occurrence of this species in Algeria and Madeira Island. Eucyclops azorensis was formerly considered to be a subspecies of E. agiloides (East Africa); therefore, the latter species is redescribed here as well based on type and non-type material. Morphological comparisons between E. azorensis, E. agiloides and other taxa (E. serrulatus and E. roseus), assumed to be closely related to our target species, support a closer relationship between E. azorensis and E. serrulatus (Palearctic) than between E. azorensis and E. agiloides (Afrotropical). The slight differences between E. azorensis and E. serrulatus in the surface ornamentation of the antennal coxobasis and intercoxal sclerites of legs 1 and 4 suggest a relatively young separation of these lineages. Eucyclops agiloides is morphologically close to E. roseus (temperate and subtropical Asia, southeastern Europe, East Africa). The numerous and clear-cut differences indicate a species rather than subspecies-level differentiation between E. agiloides and E. roseus, unlike what was formerly proposed in the taxonomic literature
An overview of the limnetic Cyclopidae (Crustacea, Copepoda) of the Philippines, with emphasis on Mesocyclops
Approximately 120 (sub)species of Cyclopidae have been reported from South and Southeast (SE) Asia, where the Philippine archipelago â with 16 (including two endemic) taxa â is one of the least explored parts of the region. Our study, part of current efforts to assess freshwater biodiversity, was undertaken to update the diversity and geographic distribution of the cyclopid copepods living in the limnetic zone of the freshwater lakes in the Philippines. Examination of the samples from 22 lakes in five islands (Luzon, Mindoro, Cebu, Leyte and Mindanao) revealed a novel species from lake Siloton (Mindanao), Mesocyclops augusti n. sp. The new species can be distinguished from the congeners by the surface ornamentation of the hindgut, among others. The same character state was found in a Mesocyclops from North Vietnam, which is provisionally identified as M. augusti n. sp., though the Vietnam and Mindanao specimens differ in a few (yet polymorphic in the close relatives) characters. Mesocyclops microlasius Kiefer, 1981 endemic to the Philippines is redescribed, based on females and males from lake Paoay (North Luzon). Sister relationships of M. augusti n. sp. and M. microlasius were tested in a phylogenetic analysis that included the closely related Old World representatives of the genus. The max. parsimony trees show M. dissimilis Defaye et Kawabata, 1993 (East Asia) as the closest relative of M. augusti n. sp. (Mindanao, Vietnam), and support sister relationship between M. geminus Holynska, 2000 (East Borneo) and M. microlasius (Luzon, Mindanao). A mainland clade (M. francisci, M. parentium, M. woutersi, M. dissimilis, M. augusti) appears in most reconstructions; all members of the clade occur in continental Asia though some species also live in islands that have never been connected to the SE Asian shelf. In most trees with the mainland clade the insular taxa (M. microlasius, M. geminus, M. friendorum) form either a paraphyletic (basal to mainland) or monophyletic sister group of the mainland clade. We also established the first records of Thermocyclops taihokuensis (Harada, 1931) in the Philippines (Luzon), so far known from East and Central Asia. In all, 11 taxa [Mesocyclops (4), Thermocyclops (4), Microcyclops (1), Tropocyclops (1) and Paracyclops (1)] including only one endemic species (M. microlasius) have so far been found in the limnetic waters. We expect significantly higher diversity and higher rate of endemism of the freshwater cyclopids in the littoral (paludal) and subterranean habitats in the Philippines
Front Matter
Freshwater Invertebrates of Southeast Asia: biodiversity and originProceedings Guest Editors Kay Van Damme (University of Birmingham, UK) Maria K. HoĆyĆska (Museum and Institute of Zoology, Polish Academy of Sciences, Warsaw, Poland) La-orsri Sanoamuang (Mahasarakham University, Maha Sarakham, Thailand)Â </p