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Two New Species Of Rhaphiomidas (Diptera: Mydidae)
Abstract and Figures
Two new species of Mydidae, Rhaphiomidas pachyrhynchus sp. nov. and Rhaphiomidas moapa sp. nov. are described and illustrated here for the first time. Rhaphiomidas pachyrhynchus represents the southeastern most record of the genus. Notes on the adult ecology of R. moapa are given.
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... Mydas flies appear to be very seasonal in the UAE and are not observed every year. A mydas fly new to science and only discovered in a Nevadan desert in the United States in 2007 appears to be absent in years of drought and was only recorded in years of moderate or heavy rainfall (Rogers and Van Dam 2007), and it is possible that in the UAE E. arabicus follows a similar pattern. In the United States, another species of mydas fly is the only true fly that has been listed as 'endangered' under the U.S. Endangered Species Act due to its restricted habitat range and the threat of habitat loss (Rogers and van Dam 2007). ...
... A mydas fly new to science and only discovered in a Nevadan desert in the United States in 2007 appears to be absent in years of drought and was only recorded in years of moderate or heavy rainfall (Rogers and Van Dam 2007), and it is possible that in the UAE E. arabicus follows a similar pattern. In the United States, another species of mydas fly is the only true fly that has been listed as 'endangered' under the U.S. Endangered Species Act due to its restricted habitat range and the threat of habitat loss (Rogers and van Dam 2007). Mydas flies in the UAE are likely also vulnerable to habitat loss and degradation, requiring research to learn more about their ecology. ...
Despite harsh climatic conditions and low and erratic rainfall patterns, the United Arab Emirates’ (UAE) terrestrial arthropod fauna is diverse and extremely well adapted to the local environment, with some species occurring in high abundance. Until recently, the UAE’s terrestrial arthropods were poorly studied. The past two decades have seen the knowledge of arthropod diversity increase dramatically, with more than 4000 species now known to occur in the Emirates, including hundreds of species that were previously unknown for the UAE and had never been recorded globally. With so many species recently added to the inventory of the nation, their ecology (i.e., life cycles, interactions, habitat needs) are yet to be studied. This presents a challenge for conservation planning, but also offers many opportunities for further study of these organisms. Where the life-histories of species are known, they demonstrate that arthropods of the UAE are an integral part of local food webs and contribute essential ecosystem services. As is the case globally, the UAE’s arthropods are under threat from habitat loss and destruction. The lack of long-term monitoring programs means that it is currently not possible to assess whether the trend of arthropod biodiversity loss seen worldwide is echoed in the UAE.
... Specimen data for Rhaphiomidas were acquired from museum collections (EMEC, CAS, UCR, LACM) and previously published literature (Cazier, 1985;Rogers & Van Dam, 2007;Rogers & Mattoni, 1993;Van Dam, 2010), as well as from the personal collection of M.H.V.D. Locations were georeferenced in ArcGIS (ESRI, 2013) and were recorded in both WGS_84 (degrees-minutes-seconds) and Lambert Conformal Conic projection required for Daymet georeferencing (http://daymet.ornl.gov/datas upport). ...
Aim
Phenology, the temporal response of a population to its climate, is a crucial behavioral trait shared across life on earth. How species adapt their phenologies to climate change is poorly understood but critical in understanding how species will respond to future change. We use a group of flies ( Rhaphiomidas ) endemic to the North American deserts to understand how species adapt to changing climatic conditions. Here we explore a novel approach for taxa with constrained phenologies aimed to accurately model their environmental niche and relate this to phenological and morphological adaptations in a phylogenetic context.
Taxon
Insecta, Diptera, Mydidae, Rhaphiomidas
Location
North America, Mojave, Sonoran and Chihuahuan Deserts.
Methods
We gathered geographical and phenological occurrence data for the entire genus Rhaphiomidas , and, estimated a time calibrated phylogeny. We compared Daymet derived temperature values for a species adult occurrence period (phenology) with those derived from WorldClim data that is partitioned by month or quarter to examine what effect using more precise data has on capturing a species' environmental niche. We then examined to what extent phylogenetic signal in phenological traits, climate tolerance and morphology can inform us about how species adapt to different environmental regimes.
Results
We found that the Bioclim temperature data, which are averages across monthly intervals, poorly represent the climate windows to which adult flies are actually adapted. Using temporally-relevant climate data, we show that many species use a combination of morphological and phenological changes to adapt to different climate regimes. There are also instances where species changed only phenology to track a climate type or only morphology to adapt to different environments.
Main Conclusions
Without using a fine-scale phenological data approach, identifying environmental adaptations could be misleading because the data do not represent the conditions the animals are actually experiencing. We find that fine-scale phenological niche models are needed when assessing taxa that have a discrete phenological window that is key to their survival, accurately linking environment to morphology and phenology. Using this approach, we show that Rhaphiomidas use a combination of niche tracking and adaptation to persist in new niches. Modeling the effect of phenology on such species' niches will be critical for better predictions of how these species might respond to future climate change.
... The larvae are restricted to deep sandy soils and are believed to be generalist predators. Several species are of threatened status, for example, R. terminatus, R. trochilus and R. moapa (Rogers & Van Dam, 2007). Rhaphiomidas terminatus terminatus is only known from 20 ha, in the middle of a golf course on the Palos Verdes Peninsula (George & Mattoni, 2006). ...
Aim
To examine the role of geological history, connectivity and distance in shaping the biogeographical structure of North American desert clades that are restricted to habitat islands (sand dunes and relictual aquatic habitats), using statistical model choice on old and new probabilistic biogeographical models.
Location
North America, Mojave, Sonoran and Chihuahuan Deserts.
Materials and methods
Dated phylogenies were estimated for three field‐sampled insect clades ( Trigonoscuta , Rhaphiomidas and sand treader crickets), and five other literature‐sampled clades (the snails Assiminea , Pyrgulopsis and Tryonia ; the desert fringe‐toed lizard Uma ; and the desert pupfish Cyprinodon ). BioGeo BEARS was used to statistically compare biogeographical models assuming unconstrained or connectivity‐constrained dispersal, with or without founder‐event speciation (jump dispersal) permitted. Finally, we introduce and test a novel distance‐based dispersal model (+x) where dispersal probability is multiplied by distance to the power x .
Results
We observed little concordance between biogeographical patterns and timing of geological events. Model comparisons were decidedly in favour of inclusion of founder‐event speciation in the models for most taxa, with only a small taxon, Uma , showing support for the model favouring vicariance. The inclusion of a constrained‐dispersal matrix was favoured by three of the eight taxa examined ( Cyprinodon , sand treader crickets, and Trigonoscuta ). Surprisingly, tests for distance influencing dispersal probability were mostly negative.
Main conclusions
Our results do not show support for any one geological event shaping the biogeographical patterns of these desert taxa. Instead, the histories of desert dune and aquatic taxa are largely products of rare jump dispersal events, and can be considered island‐like systems. Although results are negative for the distance‐based dispersal model, this in itself demonstrates the superiority of explicit statistical model testing over a priori assumption of fixed models in historical biogeography.
... The larvae are restricted to deep sandy soils and are believed to be generalist predators. Several species are of threatened status, for example, R. terminatus, R. trochilus and R. moapa (Rogers & Van Dam, 2007). Rhaphiomidas terminatus terminatus is only known from 20 ha, in the middle of a golf course on the Palos Verdes Peninsula (George & Mattoni, 2006). ...
Island systems have been indispensablein understanding the processes generating biodiversity. Examples from the Galapagos, Caribbeanand Hawaiian archipelagos demonstrate the utility of islands for the study ofadaptation, community assembly, and speciation. In addition to oceanic islands,habitat islands are also of great interest to evolutionary biologists. Unlike oceanic islands, habitat islandsare discrete patches of habitat surrounded by a contrasting habitat that islikely to change through time. Barriers between the different habitats may bemore or less stringent for some taxa. This is a notable difference, as the rules governing dispersal andvicariance may not be the same between oceanic and habitat islands. A study of sand dunes, a habitat islandsystem, in the desert southwest of North America will provide insight into theways in which dispersal and vicariance operate in this unique islandsystem. To do this I propose to examinethe comparative phylogeographic histories of three different insectgroups. My focal taxa include thegiant flower loving flies Rhaphiomidas(Diptera), flightless sand treader crickets Macrobaenetes and Ammobaenetes (Orthoptera) and flightless weevils Trigonoscuta (Coleoptera). I will present the current phylogenies for these taxa and their majorbiogeographic patterns.
... The genus Rhaphiomidas Osten Sacken, 1877 consists of 23 species and 5 subspecies. Since Cazier's (1985) revision there have been five additions to the genus including the species described here (Rogers 1993; Rogers & Van Dam 2007). This paper describes one new species Rhaphiomidas ballmeri sp. ...
This paper describes one new species, Rhaphiomidas ballmeri sp. nov. from Sonora state, Mexico. A new key is provided for males of this genus to aid in their identification.
The Early Cretaceous mydid genus and species Cretomydas santanensis is revised on the basis of a new specimen, allowing to precise its relationships within the ‘advanced Mydidae’, probably close to the subfamily Diochlistinae. This extant group has a ‘Gondwanan’ distribution, known from Southern South America and Australia, in accordance with its possible great antiquity in the Early Cretaceous. The presence of an ‘advanced Mydidae’ during the Cretaceous also suggests a greater antiquity for this family.
Twenty members of the fly families Apioceridae and Mydidae are compared in terms of 77 adult characters. Cladistic analysis of 91 synapomorphies provides a well corroborated reconstruction of lineage relationships, and reveals that the Apioceridae is paraphyletic with respect to the Mydidae. In order to render the Apioceridae monophyletic, the genus Rhaphiomidas and the subfamily Megascelinae of the Apioceridae are transferred to the Mydidae. The subfamily Rhaphiomidinae is reinstated to accommodate Rhaphiomides, comprising the most plesiomorphic mydids. The relationships of the remaining subfamilies of Mydidae are discussed in the context of these findings. The genus Apiocera is divided into four subgenera, the type subgenus Apiocera Westwood in Australia, Pyrocera subgen. nov. in North America, and the subgenera Ripidosyrma Hermann and Anypenus Philippi are applied to the South African and South American species, respectively. A key to the four subgenera of Apiocera is provided. The biogeographic relationships of the subgenera and genera of the Apioceridae and the Megascelinae are discussed. Although considered an example of a transantarctic or Gondwanan group, we argue that the distribution of the Apioceridae predates the Mesozoic supercontinent Gondwanaland and extends onto sections of Pangaea, and should be termed 'Pangaean'. The cladistic relationships between the genera of Apioceridae and Megascelinae are consistent with the geological vicariance of the fragments of Pangaea on which they now occur. (C) 1996 The Linnean Society of London.
The Delhi Sands Flower-loving Fly (Rhaphiomidas terminatus abdominalis Cazier), the only Dipteran listed as endangered in the United States, is a large, nectar-feeding pollinator fly, found only in remnants of a sand dune ecosystem in southern California. A five-year observational study was conducted in a 3.7ha preserve. Legal and biological constraints limit accuracy of population data because marking individuals was not possible. The population on the preserve appeared to be stable over the period of observation. Little variation in number of flies observed from year to year was found. Spatial distribution of fly observations differed for each fly generation, but reasons for this are not clear. Distribution of male and female flies differed from each other most of the time. Understanding aspects of the fly's ecology and behavior and the ecosystem dynamics is necessary to effectively plan for conservation and recovery of the species. Preserves must provide all of the elements needed for continued survival of the species through maintenance of its dynamic habitat.
Rhaphiomidas terminatus terminatus has been assumed extinct for over 30 years. In July of 2001 a small population was rediscovered. We provide a brief review of the known biology of Rhaphiomidas species and specifically address conservation concerns for R. terminatus terminatus.
The Delhi Sands flower-loving fly, Rhaphiomidas terminatus abdominalis Cazier, is the only dipteran listed as an endangered species by the U.S. Fish and Wildlife Service. Fewer than 500 individuals are believed to exist. Needs of this species are not well known, and understanding the behavior of this species may be a key element in designing a successful conservation and recovery plan. Behavior of adult flies was observed throughout 2 annual periods of activity (August-September) at a 3.7-ha preserve in southern California. Microhabitats present on the preserve included a range from dense shrubs (vegetation cover >75%) to open sand (vegetation cover <1%). Males and females differed greatly from each other in activity rate, specific behaviors, and use of habitat features. Males were very active, exhibited searching and pursuit flight, and were most often found in open areas. Females were more passive, spending most of the time perched on shrubs in areas with cover of >25%. While perched, females extended and vibrated their abdomens, which is postulated to be pheromone broadcast or semaphoring behavior. Flies appeared to be highly selective of microhabitats used for various behaviors, using only a small portion of the preserve, and males and females used different microhabitats. Preservation of a range of microhabitats is probably necessary to conserve the species, and habitat creation should include a range of microhabitats and plant species.
Twenty members of the fly families Apioceridae and Mydidae are compared in terms of 77 adult characters. Cladistic analysis of 91 synapomorphies provides a well corroborated reconstruction of lineage relationships, and reveals that the Apioceridae is paraphyletic with respect to the Mydidae. In order to render the Apioceridae monophyletic, the genus Rhaphiomidas and the subfamily Megascelinae of the Apioceridae are transferred to the Mydidae. The subfamily Rhaphiomidinae is reinstated to accommodate Rhaphiomidas, comprising the most plesiomorphic mydids. The relationships of the remaining subfamilies of Mydidae are discussed in the context of these findings. The genus Apiocera is divided into four subgenera, the type subgenus Apiocera Westwood in Australia, Pyrocera subgen. nov. in North America, and the subgenera Ripidosyrma Hermann and Anypenus Philippi are applied to the South African and South American species, respectively. A key to the four subgenera of Apiocera is provided. The biogeographic relationships of the subgenera and genera of the Apioceridae and the Megascelinae are discussed. Although considered an example of a transantarctic or Gondwanan group, we argue that the distribution of the Apioceridae predates the Mesozoic supercontinent Gondwanaland and extends onto sections of Pangaea, and should be termed ‘Pangaean'. The cladistic relationships between the genera of Apioceridae and Megascelinae are consistent with the geological vicariance of the fragments of Pangaea on which they now occur.
Upscaling is the term used to describe the process of going from a fine scale, detailed model of a physical system to a coarser scale, less detailed description. It is particularly appropriate in modelling flows in natural porous media (for example in the oil industry or in groundwater flows) because the fluctuations in flow properties of geological systems occur on many length scales from microns to kilometres whereas we often only need to resolve the flow on the scale of tens or hundreds of metres. There is a great deal of uncertainty about the actual spatial distribution of the geological heterogeneities in a given system, which leads to uncertainty in performance prediction. Currently the only way to predict the statistics of the predicted performance is to sample realisations of the geological heterogeneity and then run these through a deterministic numerical flow simulation and thereby sample the flow statistics. Although in some cases it is possible to construct some moments of the distribution analytically. In this paper we suggest an alternative strategy, which is to derive the probability distribution of the saturation and its time evolution. We propose a path integral solution for this and indicate how upscaling (or renormalisation) of this path integral formulation can be done formally to give the appropriate, upscaled probability distribution. In this paper we establish the formalism of the path integral for the nonlinear Buckley–Leverett problem but at this stage we only present upscaling for a much simpler linear transport problem. The advantage of this path integral is that it gives an explicit representation of the entire probability distribution from which all other information (e.g., moments) can be obtained.
Observations on the natural history and conservation biology of the giant flower loving flies, Rhaphiomidas (Diptera: Apioceridae)
- R Rogers
- R Mattoni
Rogers, R. & Mattoni, R. (1993) Observations on the natural history and conservation biology of the giant flower loving
flies, Rhaphiomidas (Diptera: Apioceridae). Dipterological Research 4(1), 21-34.
A revision of the North American flies belonging to the genus Rhaphiomidas (Diptera, Apioceridae)
- M A Cazier
Cazier, M.A. (1985) A revision of the North American flies belonging to the genus Rhaphiomidas (Diptera, Apioceridae). Bulletin American Museum Natural History, 182(2), 183-263.
Systematic position of the genus Rhaphiomidas Osten-Sacken, 1877 (Diptera, Mydidae) in the superfamily Asiloidea based on the structure of the muscles of male genitalia
- O G Ovtshinnikova
Ovtshinnikova, O.G. (2003) Systematic position of the genus Rhaphiomidas Osten-Sacken, 1877 (Diptera, Mydidae) in
the superfamily Asiloidea based on the structure of the muscles of male genitalia. Entomologicheskoe Obozrenie,
82(3), 771-778.