Biodiversity Data Journal :
Taxonomic paper
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Corresponding author:
Academic editor: Pierfilippo Cerretti
Received: 26 Aug 2015 | Accepted: 01 Oct 2015 | Published: 05 Oct 2015
© 2015 Anna Solecki, Terry Wheeler
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Solecki A, Wheeler T (2015) A new species of Neossos Malloch (Diptera: Heleomyzidae) from the Yukon Territory, Canada, and a revised key to the Nearctic species. Biodiversity Data Journal 3: e6351. https://doi.org/10.3897/BDJ.3.e6351
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The rarely collected genus Neossos Malloch contains three Nearctic and one western European species. Most known specimens have been collected from bird nests. Two specimens of an undescribed species of Neossos were collected by sweeping in subarctic tundra and a mesic meadow in the Yukon Territory, Canada. This represents a significant northward extension of the known Nearctic range of the genus.
Neossos tombstonensis sp. n. is described from the Yukon Territory. This represents the fourth described Nearctic species of Neossos. Although the type specimens were collected by sweeping, the species is predicted to be associated with bird nests, based on habits of other members of the genus. A revised key to the Nearctic species of Neossos is provided.
Taxonomy, acalyptrate, Beringia
Neossos Malloch, 1927 is a rarely collected genus of acalyptrate Diptera primarily associated with bird nests, where the larvae are apparently saprophagous in nest material.
Field-collected specimens were preserved in 95% ethanol and subsequently chemically dried using Hexamethyldisilazane. Type specimens are deposited in the Lyman Entomological Museum, McGill University, Ste-Anne-de-Bellevue, QC, Canada (LEMQ) and have been assigned unique specimen identifiers in the format LEM0000000. Genitalic dissection of the male holotype was made by detaching the posterior part of the abdomen, and heating it in 85% lactic acid on a heating plate for 10 minutes. Cleared genitalia were transferred to glycerin for examination and drawing, then stored in glycerin in a plastic microvial pinned with the specimen.
Generic characters as described by
Epandrium brown, rounded, wider than high; hypandrium pale brown, ventral hypandrial process with 9 setae; surstylus with outer lobe roughly triangular, narrowing distinctly in basal half; postgonite large; distiphallus with fine setulae for most of length except distally; epiphallus clavate (Figs
The species is named for the Tombstone Mountains and Tombstone Territorial Park, where the holotype specimen was collected.
Known only from the southern and central Yukon Territory, Canada.
Key to the Nearctic species of Neossos Although there are species-level differences in the shape of the male surstylus and epiphallus, the former is highly dependent on angle of view and the latter is subject to variation based on the preservation of the specimen and degree of collapse of the epiphallus. Both characters should be interpreted with caution. |
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1 | Hind tibia expanded apically in anterior view, diameter at insertion of pre-apical dorsal seta at least 1.38 times diameter at midpoint of tibia and 3 times diameter at base (Fig. |
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– | Hind tibia not obviously expanded apically, diameter at insertion of pre-apical dorsal seta 1.2 times diameter at midpoint of tibia, and less than twice diameter at base (Fig. |
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2 | Frons yellow-brown to brown posteriorly, never black; gena with 4–5 setae; median row of acrostichal setulae weak or absent; posterior and anterior thoracic spiracles the same size; outer lobe of surstylus narrowing sharply in apical third in lateral view. Western Nearctic (AZ, CA, UT, BC) | Neossos californicus |
– | Frons dark-brown or black posteriorly; gena with 5–8 setae; median row of acrostichal setulae present; posterior thoracic spiracle larger than anterior spiracle; outer lobe of surstylus narrowing evenly in apical third in lateral view. Eastern Nearctic (QC) | Neossos atlanticus |
3 | Frons dark yellow posteriorly; proepimeron, proepisternum, anepisternum, katepisternum and anepimeron paler than scutum; surstylus narrowing evenly to apex in lateral view. Eastern Nearctic (MD, QC) | Neossos marylandicus |
– | Frons black posteriorly; proepisternum, proepimeron, anepisternum, katepisternum, anepimeron, same colour as scutum; surstylus narrowing sharply in middle in lateral view. Northwestern Nearctic (YT) | Neossos tombstonensis |
Because they are apparently obligate associates of bird nests, specimens of Neossos are rarely collected. Of approximately 130 specimens studied by
The types of N. tombstonensis were collected in two distinct habitats. The North Fork Pass site is a wet tundra meadow north of treeline in the Ogilvie Mountain ranges. Dominant vegetation includes sphagnum mosses, grasses, sedges and ericaceous shrubs over a substrate with extensive permafrost. In contrast, the Robinson Road House site is a mesic meadow with a diverse assemblage of herbaceous plants dominated by Asteraceae, Fabaceae, and Poaceae, on a sand substrate in a clearing surrounded by spruce-pine-aspen forest.
Based on the known habits of the other described species of Neossos, it is likely that N. tombstonensis is also a nest associate. Each of the other three Nearctic species exploits a different microhabitat and host group: Neossos marylandicus in association with cavity-nesting passerines; N. californicus in raptor nests; and N. atlanticus in nests of cliff-nesting seabirds (
The Northern Biodiversity Program field party that collected the holotype included Kathrin Sim and Ruben Cordero, in addition to the authors, and we thank them for their efforts. Fieldwork was carried out under a Scientists and Explorers License from the Yukon Government, and a collecting permit from Tombstone Territorial Park. Major funding was provided by: a Natural Sciences and Engineering Research Council of Canada (NSERC) Strategic Project Grant to CM Buddle, DC Currie and TA Wheeler; NSERC Discovery Grant and Northern Research Supplement to TA Wheeler; and a W. Garfield Weston Award for Northern Research from the W. Garfield Weston Foundation in partnership with the Association of Canadian Universities for Northern Studies to AM Solecki.
AMS and TAW carried out field work, all analyses, and contributed to writing the manuscript.