Checklist of British and Irish Hymenoptera - Sawflies, ‘Symphyta’

The superfamilies Cephoidea, Orussoidea, Pamphilioidea, Siricoidea, Tenthredinoidea, Xiphydrioidea and Xyeloidea are combined as one checklist section, as the sawflies represent a distinctive assemblage of phytophagous (except Orussidae) Hymenoptera. More than fifty years have passed since the publication of the final part of Robert B. Benson’s three part identification key to the “Symphyta” of the British Isles (Benson 1935, Benson 1952, Benson 1958). Whilst the first two parts were based substantially on the acute monography by Eduard Enslin (Enslin 1912, Enslin 1913, Enslin 1914, Enslin 1915, Enslin 1916, Enslin 1917 and Enslin 1918), Benson’s treatment of the Nematinae represented an original and significant step forward in our knowledge of this subfamily. The results of subsequent research on the British and Irish sawfly fauna were collated by Quinlan (1978). Since then, renewed investigation of the taxonomy of West Palaearctic sawflies has led to a great number of taxonomic and nomenclatural changes, affecting many taxa occurring in the British Isles. 
 
Of particular value in accessing the extensive but widely scattered literature on sawflies, is the online database “Electronic World Catalog of Symphyta (ECatSym)” (Blank et al. 2012). Unfortunately, the only identification guide to the European “Symphyta” published since 1958 with a more than local geographical scope, by Zhelochovtsev (1988), suffers from weaknesses, such as the reliance placed on the opinions and illustrations of E. Lindqvist in its treatment of the Nematinae. Mistakes in translation from Russian make the later English language edition of this work even more difficult to use. 
 
Special problems are attached to the interpretation of records for some species not found in the British Isles since their inclusion in the works of Leach (1817) and Stephens (1835). Some of these are probably extinct, but their presence in the British Isles has in many cases never been unequivocally proved: see for example Benson (1943). We therefore maintain the practice, as in Fitton et al. (1978), of marking names of such taxa with a preceding “?”. Further, the taxonomic status of some of the nominal taxa described from the British Isles by Hill, Stephens, Newman and Cameron is still unclear, particularly where no type material has been located. The number of confirmed British sawfly species now stands at 537, compared to 471 in the 1978 checklist (Quinlan 1978; Broad 2014). Note that, since the publication of the introduction section (Broad 2014) a further family, Heptamelidae, has been recognised (Malm and Nyman 2014), including two British species previously included in Tenthredinidae. 
 
Authorship and date of publication of original descriptions by various authors follow mainly the bibliographic research of Taeger and Blank (1996), Taeger and Blank (2006), Blank and Taeger (1998), Blank et al. (2009) and Taeger et al. (2010). 
 
The classification of genera used here is largely based on the system of Benson (1951-1958). This has the advantages of being relatively simple and widely known. Detailed phylogenetic studies on several major lineages of Tenthredinidae are still lacking. However, some definite conclusions on generic groupings were reached by Nyman et al. (2006) on the Nematinae and Leppanen et al. (2012) on the Fenusini of the Blennocampinae. For the higher Nematinae, the full taxonomic and nomenclatural consequences of the recently proposed phylogeny have not yet been drawn. Far fewer genera will in future be recognised. For the present, we revert here to a generic classification that is similar to that used by Benson (1958), even though we are aware that Pachynematus, for example, is not monophyletic. 
 
Genus and species group names are included selectively in the synonymy. For a complete current synonymy of all these, including important misidentifications, see ECatSym (Blank et al. 2012). A name is only included as a synonym when it fulfils one or both of the following criteria: 
 
 
has at some time been used for a taxon occurring in the British Isles; 
 
 
is used in widely consulted works on taxonomy or distribution, or in original accounts of biological characters / descriptions of immature stages. 
 
 
 
The general scope and rationale for the checklist are covered by Broad (2014). As for the rest of the checklist, the Channel Islands fauna is excluded: see Sheppard (1990) on the sawfly fauna of the Channel Islands. There is a lack of data on the sawflies of the Isle of Man. It should be noted that several species were mistakenly listed as occurring in Scotland by Liston (1995). 
 
Some of the diversity of British sawflies is illustrated in Figs 1, ​,2,2, ​,3,3, ​,44. 
 
 
 
Representative British sawflies, superfamilies Cephoidea, Pamphilioidea and Siricoidea. 
 
Figure 1a. 
 
 
 
 
 
Cephidae, Phylloecus xanthostoma (G. Knight)


Introduction
The superfamilies Cephoidea, Orussoidea, Pamphilioidea, Siricoidea, Tenthredinoidea, Xiphydrioidea and Xyeloidea are combined as one checklist section, as the sawflies represent a distinctive assemblage of phytophagous (except Orussidae) Hymenoptera. More than fifty years have passed since the publication of the final part of Robert B. Benson's three part identification key to the "Symphyta" of the British Isles (Benson 1935, Benson 1952, Benson 1958. Whilst the first two parts were based substantially on the acute monography by Eduard Enslin (Enslin 1912, Enslin 1913, Enslin 1914, Enslin 1915, Enslin 1916, Enslin 1917and Enslin 1918), Benson's treatment of the Nematinae represented an original and significant step forward in our knowledge of this subfamily. The results of subsequent research on the British and Irish sawfly fauna were collated by . Since then, renewed investigation of the taxonomy of West Palaearctic sawflies has led to a great number of taxonomic and nomenclatural changes, affecting many taxa occurring in the British Isles.
Of particular value in accessing the extensive but widely scattered literature on sawflies, is the online database "Electronic World Catalog of Symphyta (ECatSym)" ). Unfortunately, the only identification guide to the European "Symphyta" published since 1958 with a more than local geographical scope, by Zhelochovtsev (1988), suffers from weaknesses, such as the reliance placed on the opinions and illustrations of E. Lindqvist in its treatment of the Nematinae. Mistakes in translation from Russian make the later English language edition of this work even more difficult to use.
Special problems are attached to the interpretation of records for some species not found in the British Isles since their inclusion in the works of Leach (1817) and Stephens (1835). Some of these are probably extinct, but their presence in the British Isles has in many cases never been unequivocally proved: see for example Benson (1943). We therefore maintain the practice, as in , of marking names of such taxa with a preceding "?". Further, the taxonomic status of some of the nominal taxa described from the British Isles by Hill, Stephens, Newman and Cameron is still unclear, particularly where no type material has been located. The number of confirmed British sawfly species now stands at 537, compared to 471 in the 1978 checklist Broad 2014). Note that, since the publication of the introduction section (Broad 2014) a further family, Heptamelidae, has been recognised (Malm and Nyman 2014), including two British species previously included in Tenthredinidae.
Authorship and date of publication of original descriptions by various authors follow mainly the bibliographic research of Taeger and Blank (1996), Taeger and Blank (2006), , Blank et al. (2009) and .
The classification of genera used here is largely based on the system of Benson (1951Benson ( -1958. This has the advantages of being relatively simple and widely known. Detailed phylogenetic studies on several major lineages of Tenthredinidae are still lacking. However, some definite conclusions on generic groupings were reached by Nyman et al. (2006) on the Nematinae and Leppänen et al. (2012) on the Fenusini of the Blennocampinae. For the higher Nematinae, the full taxonomic and nomenclatural consequences of the recently proposed phylogeny have not yet been drawn. Far fewer genera will in future be recognised. For the present, we revert here to a generic classification that is similar to that used by Benson (1958), even though we are aware that Pachynematus, for example, is not monophyletic.
Genus and species group names are included selectively in the synonymy. For a complete current synonymy of all these, including important misidentifications, see ECatSym (Blank et al. 2012). A name is only included as a synonym when it fulfils one or both of the following criteria: • has at some time been used for a taxon occurring in the British Isles; • is used in widely consulted works on taxonomy or distribution, or in original accounts of biological characters / descriptions of immature stages.
The general scope and rationale for the checklist are covered by Broad (2014). As for the rest of the checklist, the Channel Islands fauna is excluded: see Sheppard (1990) on the sawfly fauna of the Channel Islands. There is a lack of data on the sawflies of the Isle of Man. It should be noted that several species were mistakenly listed as occurring in Scotland by Liston (1995). bimaculata (Donovan, 1808, Sirex) cedrorum (Smith, 1860, Sirex) fantoma (Fabricius, 1781) Distribution: England, Scotland, Ireland Notes: Established in Ireland. Urocerus augur, U. fantoma and U. tardigradus have at times been recorded as introductions to the British Isles, but only U. augur is regarded as established (O'Connor et al. 1997). All were treated as valid species by Smith (1978), although U. tardigradus had for a long time been placed as a synonym of U. fantoma. Benson 1958 (ii, supplement to section a) added U. tardigradus to the British list with "fantoma Fabricius auctt. nec Fabricius" as its synonym and separated this in a key from "U. fantoma fantoma (= augur augur Klug)". The reasons for this treatment are not clear. No type specimens are known to exist for either U. fantoma or U. tardigradus, but Fabricius (1781) in his short original description of Sirex fantoma describes the legs as yellow, whereas U. augur has extensively black tibiae. European specimens previously identified as U. tardigradus have so far all proved to belong to U. fantoma (A. Taeger, pers. comm.). We revert here to treating U. tardigradus as a synonym of U. fantoma.

Distribution: ?England
Notes: Presence in the British Isles uncertain: see Gibbs (2006).
Phyllotoma aceris was described on the basis of specimens "bred by Mr Healy from larvae which make great blotches in the leaves of Acer campestre, and occasionally in Acer pseudo-platanus" McLachlan (1867). According to present knowledge on distribution and hostplants, the syntype series probably consisted of more than one species. The description is not sufficiently detailed to determine the identity of the specimens which McLachlan examined. No type material has been located, as already stated by Altenhofer and Zombori (1987). Nevertheless, Altenhofer and Zombori (1987)  Kaliofenusa altenhoferi Liston, 1993 Nomenclature: carpinifoliae Liston, 1993 Distribution: England, Scotland Notes: Added by Liston (1994). Synonymy with K. carpinifoliae according to Liston (1996). Dolerus pusillus Serville cannot at present be placed as conspecific with K. ulmi or K. altenhoferi, and must be treated as an unplaced species (Blank et al. 2001 Placed by Konow (1905) as a synonym of Pristiphora leucopodia (Hartig, 1837), a species which has never been found in the British Isles. Konow probably did not examine the type of N. placidus, which according to Benson (1943b), is lost. Notes: Regarded as a group of sibling (biological) species by Kopelke (1996), Kopelke (2000). These are very difficult, perhaps impossible, to distinguish using adult morphological characters. According to records of galls on various identified Salix species, at least the following three species belonging to the group occur in the pallens (Enslin, 1916, Lygaeonematus) vernalis (Lindqvist, 1937, Pteronidea)  kriegeri (Konow, 1903, Pteronus) spurcus (Konow, 1904, Amauronematus) absimilis (Lindqvist, 1939, Pteronidea) Distribution: England, Scotland, Wales, Ireland

Distribution: Scotland
Notes: Added by Knight and Liston (in prep.). Some differences between Scottish individuals and the Estonian lectotype require further investigation.
arcticola Dalla Torre, 1894 forsiusi (Enslin, 1915, Pontania) alsius (Benson, 1935, Amauronematus)  fuscarima (Benson, 1933, Pteronidea) pallescens Hartig, 1837: Cameron, 1877 misident. Notes:  regard P. clitellatus and P. fallax as morphologically highly variable species, which together include most of the previously described W. Palaearctic taxa. Their arguments for this are well reasoned, but at present it seems prudent to continue to regard several of the more distinctive morphological segregates, treated as species by Benson (1958), as separate taxa, because morphologically intermediate specimens are rare (at least in the male sex). The taxonomy of the whole group requires further intensive work, including genetic analysis. According to   coriacea (Benson, 1953, Nematus) Distribution: England, Scotland, Wales, Ireland Notes: According to Kopelke (2007c) P. coriacea is a synonym of P. leucapsis (as stated in the abstract and table 1, whereas the synonymy with P. alienata on p. 153 is wrong; J.-P. Kopelke, pers. comm.). The concept of P. leucapsis in Kopelke (2007c) is different to that of Benson (1958) and most other previous taxonomists.  .