Dolichopodidae of Portugal - dataset 2009-2018

Study Extent

Samples were retrieved from all 11 Portuguese provinces, and all districts except for Évora. In terms of number of municipalities, localities and locations, the districts of Bragança, Guarda and Faro were best covered. Next to Bragança and Guarda, the largest number of sampling sites was situated in the Porto and Coimbra districts. Over 1/3 of all samples were gathered in the Porto district, whereas more than 5% originated from (in decreasing order) Braga, Bragança, Coimbra, Guarda, Aveiro and Faro. More than 30% of the sampling sites were situated between 501 and 1,000 m a.s.l., with about 15% of them in or near the littoral zone (0–10m), and between 201 and 500 m a.s.l. The surveys in mainland Portugal were mainly conducted by Portuguese researchers between 2009 and 2016. Belgian researchers contributed to a far smaller extent: Marc Pollet (Belgium) and Anja De Braekeleer (Belgium) visited Portugal in May 2014, and Jonas Mortelmans (Belgium) added a few samples from 2018. The general aim of this project was to get a first comprehensive account of the dolichopodid fauna of mainland Portugal (thus far only 34 species had been recorded from the country). A total of 789 samples were ultimately investigated, 761 of which contained Dolichopodidae. Not taking the 53 samples collected by Marc Pollet & Anja De Braekeleer into account, between 2009 and 2016 on average 88 samples were collected per year, with peaks of 150 and 146 in 2011 and 2013 respectively, and a minimum of 46 in 2012.

Sampling

The following sampling strategy was applied by Rui Andrade and Ana Gonçalves (together they gathered about 88% of the samples): the focus of collecting during fieldwork was on various dipteran families with Dolichopodidae as one of the target taxa. Both researchers aimed at collecting all over Portugal to fill gaps in the known distribution of species. For practical reasons, a large number of sites were visited near Porto, and some of them were investigated on multiple occasions and/or during longer periods of time. For more distant collecting trips, mostly protected areas were selected on the assumption that good habitat types for Diptera were present. Rui Andrade steadily sampled Diptera in humid sites; e.g., along banks of streams and rivers, but also visited drier places in order to get a reliable idea of the extant Diptera richness. Collecting was carried out throughout the year with samples taken during every month. Most samples were collected in June, May and September (in decreasing numbers), whereas the first two and last two months of the year each produced 10 or fewer samples. About 72% of the samples and more than 86% (including those collected by Marc Pollet and Anja De Braekeleer) of the specimens were collected by sweep net which was used to gather flies from all kinds of surfaces; e.g., rocks, muddy and sandy soil, but also from tree trunks. Yellow pan traps and hand collecting accounted for 12% and 11% of the samples respectively, and produced about 6% and 7% of the specimens respectively. The other collecting methods (light trap, Malaise trap, observation, pan trap of unknown colour, pooter, rearing) together contributed about 2% (= 17) of the samples and only 0.7% (n = 47) of the specimens.

Quality Control

There was little need for any quality control during the sampling phase of this project. Collecting was mainly executed in promising sites for Diptera. A subsample of representative Diptera species (incl. Dolichopodidae) was systematically retrieved from the sweepnet by Rui Andrade and Ana Conçalves (principal collectors), whereas all Dolichopodidae were retained by Marc Pollet and Anja De Braekeleer. All samples were stored in 75% alcohol solution in cool and dark conditions.

Method steps

1. Data for this dataset are retrieved, unified and standardized from source data through a series of RMarkdown scripts and Openrefine scripts that are versioned on GitHub (https://github.com/inbo/data-publication/tree/master/datasets/portugal-dolichopodidae-occurrences) and which include the following steps:
2. Standardize the dataset to Darwin Core, sampling event dataset type. Containing a sample core and a occurrences extension.
3. Conversion of the original coordinates to decimal coordinates, WGS84
4. The resulting Darwin Core data files are uploaded to the INBO IPT and documented with metadata.
5. The dataset is published and registered with GBIF.

The collection contains 6,680 specimens of 200 different species, with 142 recognized (known), 40 new (undescribed) and 18 doubtful species of Dolichopodidae. The published dataset holds 2,137 occurrences of 145 different species (144 species and Pelastoneurus sp.) with 5,805 specimens.

1. Insecta
   common name: insects rank: class
2. Diptera
   common name: flies rank: order
3. Brachycera
   common name: true flies rank: suborder
4. Empidoidea
   rank: superfamily
5. Dolichopodidae
   common name: long-legged flies rank: family
6. Acropsilus
   rank: genus
7. Anahydrophorus
   rank: genus
8. Anepsiomyia
   rank: genus
9. Aphrosylus
   rank: genus
10. Argyra
    rank: genus
11. Campsicnemus
    rank: genus
12. Ceratopos
    rank: genus
13. Chrysotimus
    rank: genus
14. Chrysotus
    rank: genus
15. Diaphorus
    rank: genus
16. Dolichopus
    rank: genus
17. Gymnopternus
    rank: genus
18. Hercostomus
    rank: genus
19. Hydrophorus
    rank: genus
20. Liancalus
    rank: genus
21. Machaerium
    rank: genus
22. Medetera
    rank: genus
23. Muscidideicus
    rank: genus
24. Neurigona
    rank: genus
25. Orthoceratium
    rank: genus
26. Ortochile
    rank: genus
27. Parathalassius
    rank: genus
28. Pelastoneurus
    rank: genus
29. Peloropeodes
    rank: genus
30. Poecilobothrus
    rank: genus
31. Rhaphium
    rank: genus
32. Schoenophilus
    rank: genus
33. Sciapus
    rank: genus
34. Sybistroma
    rank: genus
35. Sympycnus
    rank: genus
36. Syntormon
    rank: genus
37. Systenus
    rank: genus
38. Tachytrechus
    rank: genus
39. Telmaturgus
    rank: genus
40. Teuchophorus
    rank: genus
41. Thinophilus
    rank: genus
42. Thrypticus
    rank: genus
43. Xanthochlorus
    rank: genus

All mainland Portuguese provinces and all districts but one (Évora) were investigated.