Pericoma rivularis Berdén, 1954

Pericoma rivularis Berdén, 1954
Pericoma rivularis Berdén, 1954
Pericoma (Pachypericoma) bavarica Wagner, 1981 (syn. Wagner 1994)
Pericoma (Pachypericoma) rivularis Berdén, 1954 - Wagner, 1994
Pneumia rivularis (Berdén, 1954) - Omelková & Ježek, 2012

Pericoma rivularis Berdén, 1954 from eastern Norway. Photo: Gunnar Mikalsen Kvifte

Description (based on Norwegian specimens, diagnostic characters in italics):
Eye bridge consisting of 4 rows of facets.
Flagellomere 14 with an unusually elongate apiculus for a Pericoma (see note below).
Gonocoxites very stout without mesal apodemes. Gonostylus with a long narrow part and a thickened base.
Inner lamellae distally terminating behind outer lamellae. Subgenital plate deeply bilobate, aedeagal armature with transverse rows of ridges anterior to edge of subgenital plate.
5-7 spatulate retinacula.

DNA:
COI: JQ349583 (from Kvifte & Andersen 2012)
NADH: JQ767098 and JQ767099 (from Espindola et al. 2012)
cyt B: JQ767036 and JQ767037 (from Espindola et al. 2012)


Distribution:
Czech Republic (Ježek 2003)
England (Withers 1989)
Finland (Berdén, 1954)
Germany (Wagner 1981, as Pericoma bavarica Wagner, 1981)
Ireland (Withers & O'Connor 1992)
Norway (Andersen & Håland, 1995)
Primorye (Russian far East) (Wagner 1994)
Scotland (Withers 1989)
Sweden (Berdén, 1954)

Natural History:
Unknown.

Discussion:
Wagner (1981) described Pericoma bavarica from Germany. The synonymy with Pericoma rivularis is not obvious from the illustrations, but is clear from the actual specimens.
Omelková & Ježek (2012) placed Pericoma rivularis in Pneumia Enderlein, 1935 based on the elongate apiculus on the terminal flagellomere. Kvifte & Andersen (2012) pointed out that Pneumia typically have retinacula with feathery tips and eyebridges of six or seven facets and argued that the elongate apiculus is a plesiomorphy of little value in classification. The placement of Pericoma rivularis is still unclear.

Bibliography
Andersen, T. & Håland, Ø. 1995. Norwegian moth flies (Diptera: Psychodidae). Fauna Norvegica Serie B. 42: 125-130.

Berdén, S. 1954. Taxonomical notes on Psychodidae (Dipt. Nem.) II. Four new species of Pericoma from Fennoscandia. Opuscula entomologica. 19: 33-39.

Espindola, M. A., Buerki, S., Jacquier, A., Ježek, J. & Alvarez, N. 2012. Phylogenetic relationships in the subfamily Psychodinae (Diptera, Psychodidae). Zoologica Scripta. 41: 489-498.

Ježek, J. 2003. New faunistic data and check list of non Phlebotomine moth flies (Diptera, Psychodidae) from the Czech and Slovak republics. Časopis Národního muzea, Řada přírodovědná. 172: 121-132.

Kvifte, G. M. & Andersen, T. 2012. Moth flies (Diptera, Psychodidae) from Finnmark, northern Norway. Norwegian Journal of Entomology. 59: 108-119.

Omelková, M. & Ježek, J. 2012. Two new species of Pneumia Enderlein (Diptera, Psychodidae, Psychodinae) from the Palearctic region. Zootaxa. 3180: 1-18.

Wagner, R. 1981. Über einige Psychodiden (Diptera, Nematocera) aus dem Murnauer Moos. Entomofauna. 2: 47-56.

Wagner, R. 1994. On a collection of Psychodidae (Diptera) from the Far East of Russia. Studia dipterologica. 1: 75-92.

Withers, P. 1989. Moth Flies Diptera: Psychodidae. Dipterists Digest. 4: 1-83.

Withers, P. & O'Connor, J. P. 1992. A Preliminary Account of the Irish Species of Moth Fly (Diptera: Psychodidae). Proceedings of the Royal Irish Academy. Section B: Biological, Geological, and Chemical Science. 92B: 61-77.