taxonID	type	description	language	source
861187FE7879FFE577324B03E079F921.taxon	materials_examined	Material examined. Numerous specimens from Germany, Switzerland, Austria, North and South Italy, Greece and Anatolia were examined for egg structure. Biometry was additionally performed on the following: Germany: Hesse, upper course of river Fulda between Obernhausen and Ried, 11 ♂, 11 ♀; Hesse, Spessart, tributary to river Schmale Sinn, 7 ♀; Lower Saxony, Harz Mts, Hohegeiss, 1 ♀; Northrhine Westphalia, Albaum, 2 ♂, 1 ♀ (det. J. Aubert); Baden-Württemberg, river Kocher at Gaildorf, 2 ♂, 1 ♀; Bavaria, Bavarian Forest, Rotbach at Böbrachmühle, 3 ♂. Austria, Pongau, Eben, 2 ♂. Switzerland, Hochrhein at Sargans, 3 ♂, 2 ♀. Turkey, Armenia, Pülümür Pass, 3 ♂, 1 ♀; North Anatolia, Pass between Terfenni and Korkuteli, 1500 m, 8 ♂, 13 ♀. Assigned to P. microcephalus with doubt: Germany, Lower Saxony, Medingen, 8 ♂, 5 ♀.	en	Zwick, Peter (2011): Polymorphism And Taxonomic Problems In The Perlodes Microcephalus Group (Plecoptera: Perlodidae); Perlodes Mortoni Removed From Synonymy. Illiesia 7 (26): 291-296, DOI: http://doi.org/10.5281/zenodo.4758218
861187FE7879FFE577324B03E079F921.taxon	description	Brachypterism. Males range from strongly to barely brachypterous, several have a RWL similar to females. Wing length variation does not seem to be random but to occur stepwise. Should this be confirmed in larger samples the phenomenon might be related to number of larval instars through which specimens grew before metamorphosis. Egg structure. Sclerites on the anchor disc margin are well delimited and large. They are 2 - 3 times longer in radial direction than they are wide in peripheral direction. Sclerite orientation is oblique, sclerite tips point in a clockwise direction. Variation between specimens from central Germany, Italy (Sila Grande), or Anatolia is normally not greater than between individual platelets of the illustrated specimen (Fig. 5). However, a female from N. Italy and one from Greece, Olympus, had shorter platelets.	en	Zwick, Peter (2011): Polymorphism And Taxonomic Problems In The Perlodes Microcephalus Group (Plecoptera: Perlodidae); Perlodes Mortoni Removed From Synonymy. Illiesia 7 (26): 291-296, DOI: http://doi.org/10.5281/zenodo.4758218
861187FE7879FFE577324B03E079F921.taxon	discussion	Aberrant population. A sample from N. Germany, Medingen near Uelzen, is assigned to P. microcephalus with some doubt. Variation of male wing length (Fig. 2) seems to resemble P. microcephalus but sclerites on the egg anchor are different between specimens and resemble some of the P. mortoni eggs shown in Fig. 5. A single female of P. dispar was taken at the same site. Notes. Types of Perla microcephala are no longer available (Zwick 1972). I regard Berthélemy (1964) as first revisor in the sense of the INTERNATIONAL CODE OF ZOOLOGICAL NOMENCLATURE and follow his interpretation of the name.	en	Zwick, Peter (2011): Polymorphism And Taxonomic Problems In The Perlodes Microcephalus Group (Plecoptera: Perlodidae); Perlodes Mortoni Removed From Synonymy. Illiesia 7 (26): 291-296, DOI: http://doi.org/10.5281/zenodo.4758218
861187FE7879FFE6759C4BFFE0F7FD26.taxon	materials_examined	Material examined. Numerous specimens from Germany and the entire range between Toulouse, Sweden and Armenia were examined for egg structure. Biometry was performed on 12 ♂ and 7 ♀ from Germany, Hesse, river Fulda at Schlitz-Richthof, 10 ♂, 7 ♀ from Hungary, river Raba at Magyarlak, and single males from Rio Lozoya, central Spain; France, Pont du Gard; Sweden, R. Njva; and Armenia, Village Kasach.	en	Zwick, Peter (2011): Polymorphism And Taxonomic Problems In The Perlodes Microcephalus Group (Plecoptera: Perlodidae); Perlodes Mortoni Removed From Synonymy. Illiesia 7 (26): 291-296, DOI: http://doi.org/10.5281/zenodo.4758218
861187FE7879FFE6759C4BFFE0F7FD26.taxon	description	Brachypterism. Male wings are between 1.2 and 1.8 times as long as head width, the distribution peaks at a RLW of 1.4. In a RWL frequency distribution, males are widely separate from females. Egg structure. The anchor disc margin is covered by numerous irregularly shaped polygons which are barely sclerotized and were difficult to draw (Fig. 5). No individual or geographical variation was observed.	en	Zwick, Peter (2011): Polymorphism And Taxonomic Problems In The Perlodes Microcephalus Group (Plecoptera: Perlodidae); Perlodes Mortoni Removed From Synonymy. Illiesia 7 (26): 291-296, DOI: http://doi.org/10.5281/zenodo.4758218
861187FE7879FFE6759C4BFFE0F7FD26.taxon	discussion	Notes. Albarda (1889) studied the types of Rambur's Perlidae in coll. Selys-Longchamps. He identified the single male from Paris as " Dictyopteryx microcephala Pictet, ♂, forma microptera " which supports the present interpretation of the name. All males in samples including P. dispar females were very dark, live specimens appearing almost black and the way in which they moved to hide reminded one of rove beetles (Coleoptera: Staphylinidae).	en	Zwick, Peter (2011): Polymorphism And Taxonomic Problems In The Perlodes Microcephalus Group (Plecoptera: Perlodidae); Perlodes Mortoni Removed From Synonymy. Illiesia 7 (26): 291-296, DOI: http://doi.org/10.5281/zenodo.4758218
861187FE787AFFE076EC4B27E548F921.taxon	materials_examined	Material examined. Syntypes. The complete original material sent by K. J. Morton seems to be in Klap {lek's collection in the Natural History Museum at Praha Kunratice. Most specimens are from " Uddington, 13. iv. 1902, K. J. Morton " or very similar collecting dates, plus several specimens from Carluke, Scotland, K. J. Morton (several dates; one ♀ with " Dictyopteryx microcephala Pict. " in Morton's hand). There are also 1 ♂, 1 ♀ from " 3. v. 80 Gotha Dr. Müller " mentioned in Klap {lek (1906). Several Scottish specimens are labelled " Cotype ", only 2 ♀ from " Uddington, 13. iv. 1902, K. J. Morton " are labelled " Type ". For lack of time, biometry was not performed and only one of the latter two females was studied for eggs. Its abdomen is detached and on a card pinned with the fore body, several eggs are in Euparal on a plastic slide pinned with the specimen, plus a few eggs on a glass slide presently in my collection. Additional material. Scotland: R. Tweed at Innerleithen, 1. v. 2010, D. Pryce, under stones, 25 ♂, 15 ♀; Perthshire, Dunkeld, R. Tay, late April 1990, Andreas Zwick, 1 ♂, 1 ♀; Wales: R. Dee at Pen-y-Lan, Clwyd / Shropshire border, iii. 2004, Malaise trap, D. Pryce, 4 ♂, 3 ♀;	en	Zwick, Peter (2011): Polymorphism And Taxonomic Problems In The Perlodes Microcephalus Group (Plecoptera: Perlodidae); Perlodes Mortoni Removed From Synonymy. Illiesia 7 (26): 291-296, DOI: http://doi.org/10.5281/zenodo.4758218
861187FE787AFFE076EC4B27E548F921.taxon	description	Brachypterism. Very similar to P. dispar, male wings between 1.4 and 1.8 times as long as head width, peaking at a RWL of 1.6 (Fig. 4). Egg structure (Fig. 5). Sclerites on the anchor disc margin differ extremely between specimens taken together, ranging from relatively large plates longer than wide and in one case also with a clockwise twist (mo- 3) to irregularly shaped sclerites placed at distances from each other along the disc periphery, to a single row of short, transverse sclerites (mo- 5), and ultimately, numerous small sclerites which on their medial edge may not be clearly separate from very small sclerotized patches (mo- 6, mo- 7). The spectrum of observed character expressions was similar between British rivers, there were more specimens with relatively small than with large sclerites. There are no clear differences from the presumed aberrant population of P. microcephalus from Medingen, N. Germany. Unlike in P. dispar, brown pigmentation and sclerotization of structures along the anchor disc margin were always expressed.	en	Zwick, Peter (2011): Polymorphism And Taxonomic Problems In The Perlodes Microcephalus Group (Plecoptera: Perlodidae); Perlodes Mortoni Removed From Synonymy. Illiesia 7 (26): 291-296, DOI: http://doi.org/10.5281/zenodo.4758218
861187FE787AFFE076EC4B27E548F921.taxon	discussion	Notes. Illies (1955) formally synonymized P. mortoni with P. microcephalus. Evidence for this decision was not mentioned. Historical specimen labels reveal that K. J. Morton had felt the same. Other students also agreed that the single British - Irish Perlodes is indeed P. microcephalus (for example, Hynes 1967, 1977, Costello 1988 a, Elliott 1992, Ashe, O'Connor & Murray 1998). Short-wingedness of the Irish Plecoptera received special attention but no male P. mortoni was available (Costello 1988 b). I abstain from the originally intended lectotype designation because: 1, not all of the evident syntypes could be adequately studied; 2, fresh material shows that egg anchor sclerites vary too much for any single specimen to represent a reference specimen characteristic of the species.	en	Zwick, Peter (2011): Polymorphism And Taxonomic Problems In The Perlodes Microcephalus Group (Plecoptera: Perlodidae); Perlodes Mortoni Removed From Synonymy. Illiesia 7 (26): 291-296, DOI: http://doi.org/10.5281/zenodo.4758218
