Recent additions to the list of German sawflies (Hymenoptera, Symphyta)

Two tenthredinid sawfly species are newly recorded in Germany: Pristiphora krausi (Lacourt, 2006) and P. melagonia sp. nov. The latter is also recorded from Greece and Spain. These species belong to the Pristiphora depressa group, as confirmed by genetic data. Additional data are presented for seven other tenthredinid species which have only rarely been recorded in Germany and for which previously-published data are incomplete. Identification keys to the West Palaearctic species of Eurhadinoceraea and the Pristiphora depressa group are included. Other species of Symphyta, first recorded in Germany since the publication of the most recent checklist, are listed in a table, with references to literature which describes identification characters.


Introduction
During the early stages of revision of the Red List of German sawflies, we realised the need to place on permanent record the still partly unpublished specimen data for some species first found or identified in Germany in recent years. Only one of the species mentioned below is included in the "Fauna Germanica" checklist of sawflies (Blank et al. 2001) and only a few of them in the most recent national list by Liston et al. (2012). Nevertheless, except for Pristiphora krausi and P. melagonia sp. nov., all these species have already been stated to occur in Germany in published works. Such data, for example in Schmidt et al. (2017), has sometimes been relegated to the "supplementary material", where it may easily be overlooked. Furthermore, the hitherto published data for German specimens of the species mentioned below are, in various respects, incomplete. As all have, so far, only rarely been found in Germany and accordingly might be considered to be in some way endangered, short notes are given on their wider range and what is known of their biology.
Identification characters of some species are described and illustrated. To complete the picture, other species first recorded in Germany since around 2012, but which have a better documented occurrence here, are listed in Table 1. This table also cites the source of the original record and sometimes additional works which contain descriptions of useful identification characters. In the list by , Athalia longifoliae Kontuniemi, 1951 was inadvertently omitted, although it was, at that time, already reliably recorded from Germany (Mol 2009).
It seems likely that taxonomic research still in progress will make further name changes necessary before the next list of all German species is published. For this reason, we do not list here the very many nomenclatural and taxonomic changes which have been made since publication of the most recent German checklist ). Most of these changes result from the treatment of several genus names as synonyms of Euura, as proposed by Prous et al. (2014). We recommend the online presentation "ECatSym" (Taeger et al. 2018) for checking on currently valid names and synonyms.
The decimal degree latitude and longitude coordinates are generally given to a precision of three decimal places, but for trapped specimens up to five decimal places are given if these are recorded on the labels of specimens.
As described in Prous et al. (2019), we sequenced three gene fragments (1078-1087 bp of CO1, 1654 bp of NaK and 2480-2696 bp of POL2) for selected Pristiphora depressa group specimens to complement previously-available data from this group. The three gene fragments were newly sequenced for one specimen each of P. depressa, P. cretica, P. krausi and P. melagonia sp. nov. In addition, for one specimen of P. tetrica, POL2 was newly sequenced to complement previously-obtained CO1 and NaK data (GenBank accessions KY698202 and KY698122). The new sequences obtained here have been submitted to NCBI GenBank (accession numbers MT385398-MT385410).
The single currently-known German specimen, above, has already been mentioned by Schmidt et al. (2017). In Europe, this circumpolar species has long been known to occur in the Alps, as well as in Scotland and Fennoscandia (Benson 1961). Its presence in the Carpathians and the Giant Mountains (Czech Republic, Bohemian Massif) was detected more recently (Zombori and Ermolenko 1999;Beneš 2013). As for all Dolerus yukonensis specimens examined from Switzerland and Scotland, the abdomen of the Bavarian specimen is completely black. Fennoscandian D. yukonensis have a well-developed red girdle on the abdomen. Morphologically, D. yukonensis is very similar to D. cothurnatus. According to Dr Mikk Heidemaa, occasional specimens of D. cothurnatus lack the red girdle which is typical of this species. However, we have not, so far, seen any such specimens. Apart from the body colour of central European specimens, characters which distinguish D. yukonensis from D. cothurnatus are: abdominal terga 2 and 3 with fine, transverse sculpture contrasting with largely unsculptured tergum 1, Fig. 1 (in cothurnatus terga 1-3 equally unsculptured and shiny, Fig. 2); hyaline wing membranes (in cothurnatus smoky) and less strongly diverging apical setae of sawsheath in dorsal view, Fig. 3 (cothurnatus, Fig. 4). Benson (1961) wrote that D. yukonensis is scarce in Central Europe: he knew of only three records from Switzerland. Kofler and Schedl (2012) indicated that D. yukonensis is also rarely re-  Lacourt, 1990 Birka alpina Lacourt, 1990 BW Jansen (2017) Lacourt (1990) Calameuta punctata (Klug, 1803) Calameuta punctata (Klug, Benson, 1960 Xyela menelaus Benson, 1960BW Jansen et al. (2018) Blank et al. (2013 corded in Austria. However, in the collection of the late Bruno Peter are approximately one hundred specimens of this species collected from localities in many areas of Switzerland, at altitudes of 800-2065 m above sea level. The host plant is almost certainly one or more species of Equisetum, based on observations of adults and because the known hosts of related Dolerus species are Equisetum. However, neither details of its biology nor a description of the larva appears to have been published.
Morphological identification of this species is possible using the characters described by Prous (2012). The larval host plant is unknown. Lacourt (1993) speculated that it could be Alchemilla vulgaris L., but gave no explanation for his comment.
In Germany, previously only recorded from the Rosenau Nature Reserve, which, like Sammern, supports a Mesobrometum community, growing on calcareous shingle of the River Isar. Liston et al. (2019a) commented adversely on the suitability of the ovipositor characters described by Lacourt (1998) for separating Endelomyia filipendulae from the only other known European species in the genus, E. aethiops (Gmelin, 1790). Subsequent examination of a larger number of specimens suggests that the appearance of the sawsheath (i.e. valvulae 3) in dorsal view will, in fact, separate them. In E. filipendulae, the longest setae are nearly as long as the breadth of the sheath (Fig. 5), whereas in E. aethiops, they are much shorter (Fig. 6). (Zombori, 1977) Germany Eurhadinoceraea amauros is currently only known in Germany from the Rosenau Nature Reserve, where it occurs together with E. ventralis. There, larval development of both species is only on Clematis recta. At present, E. amauros is known from a rather small number of specimens collected at a few localities in central and southern Europe (Germany, Switzerland, Slovakia and Italy south into the Abruzzi). Males of E. amauros have been recorded at some southern and eastern European localities, whereas most populations of E. ventralis are entirely parthenogenetic, according to Müller et al. (2004), although Lønnve (2009) recorded males in Norway. Eurhadinoceraea amauros seems only to inhabit semi-natural, steppe-like habitats. By contrast, E. ventralis has become a nuisance in gardens, also far outside its original range, damaging numerous cultivated species (Severin 1997;Lønnve 2009).

Eurhadinoceraea amauros
Superficially, because of their similar size and largely black colouration, adult E. amauros (Fig. 7) resemble Phymatocera aterrima (Klug, 1816)  The key to the five West Palaearctic (and European) Eurhadinoceraea Enslin, 1920 species by Zombori (1977;as Sterigmos Zombori, 1977) works adequately, but could have been simplified by making more use of colour characters, which are very constant in the European species. The following key is offered as an alternative.
Only the European distribution of the species is given. Eurhadinoceraea amauros is only known in Europe, whereas the other species were all mentioned in older literature as having been recorded in the East Palaearctic. However, the presence of E. ventralis and E. fulviventris in the East Palaearctic requires checking, because several other similarly coloured species are now known there (Wei 1999). Zombori (1990) mentioned that he had captured large numbers of males and females of E. sanguinicollis at Kerecsend, but omitted any morphological description of the male, which was not previously known. We examined two males in the collection of the Hungarian Natural His- Body and legs completely black, except sometimes for small brown flecks on pronotum (Fig. 7) Enslin (1920). The differences in punctation of the mesoscutellum are evident between females of these species and probably also apply to males.

3
Abdomen entirely black or dark brown; whole thorax reddish, except for black mesosternum; legs mainly black with bases of tibiae and apices of femora obscurely paler (Fig. 8) -Thorax nearly entirely black (Fig. 11), except at most for propleuron and small fleck on posterior pronotum or, if extensively yellow, then mesepisternum entirely black (Fig. 10) Mesonotum, pronotum and mesoscutellum red-orange (Fig. 10); upper head behind eyes entirely black. Sawsheath viewed dorsally with apical setae almost straight and directed outwards (Fig. 12)  -Thorax entirely black (Fig. 11); upper head behind eyes marked with yellow-brown. Sawsheath viewed dorsally with apical setae strongly curved and directed more backwards (Fig. 13) Klug (1816) gave "Deutschland" as the type locality in the original description, which was based only on a female holotype, now apparently lost. Prous et al. (2019) remarked on the unclear label data of the single known male specimen, previously sometimes considered to have been collected in Germany, but possibly really from Denmark. Thus, the above record refers to the only extant specimen of definite German provenance.
Male: unknown. Variability. The Spanish specimen is the palest and the German specimen the darkest, with the two very similarly coloured Greek specimens intermediate.
Genetics. Mitochondrial CO1 has been sequenced from three specimens, two of which were published by Prous et al. (2017). Sequences of the specimens from Spain and Germany are identical, while the specimen from Greece (holotype) differs by 0.1-0.2%. Three nuclear genes have been sequenced from two specimens, TPI from DEI-GISHym20784 (KY698317, see Prous et al. 2017) and NaK and POL2 from the holotype DEI- GISHym80284. Closest species are P. krausi, P. tetrica and the specimen DEI-GISHym20783 from Spain (possibly an undescribed species, see Prous et al. 2017), with a minimum CO1 distance of 6.7% (P. tetrica) and a minimum nuclear DNA distance of 1.5% (P. krausi).
Host plant. The Spanish specimen was swept from Acer monspessulanum. As the known hosts of other species in the Pristiphora depressa group are all Acer species , it is likely that the larva of P. melagonia also feeds on Acer. Hosts other than A. monspessulanum must be used, because this maple species does not occur in the region of Germany where one of the paratypes was collected.
Etymology. Melagonia, a Latinised noun in the nominative singular, is derived from parts of the Greek words melas (black) and gonia (angle, corner) and refers to the angled black marking on the pronotum.
Diagnosis. In the key to north-western Palaearctic species of Pristiphora by Prous et al. (2017), P. melagonia runs to the couplet containing P. tetrica and P. depressa, but not clearly to either of these, because the supraclypeal area of P. melagonia can be partly pale or entirely black and the upper head may be marked with pale or entirely black. Externally, P. melagonia is most similar to P. depressa. External differences between these and other described West Palaearctic species are summarised in a key, below. The lancets of P. melagonia (Fig. 26) and P. depressa (Fig. 27)  Forewing costa and stigma largely brown to black (Fig. 18)

Discussion
The new data which we present are only for some species of Tenthredinidae (Tenthredinoidea). This is not because we deliberately selected this taxon from amongst the six superfamilies which comprise the German fauna of Symphyta, but merely reflects the authors' focus of interest on the Tenthredinidae, which, in the Palaearctic, is by far the largest tenthredinoid family. It can be seen from Table 1, that additional German species of other superfamilies have also been recently detected. Several of the German records, which we mention, are currently the most northern of these species in Europe, i.e. Empria granatensis, Endelomyia filipendulae, Eurhadinoceraea amauros, Pristiphora krausi and Pristiphora melagonia. However, we consider it more likely that these were previously overlooked in Germany, rather than that they are present here as the result of a recent northwards range extension caused by climate change. It may be significant, that, with the exception of P. krausi, these are species which are difficult or impossible to identify using published morphological characters. One wonders how long it might have taken to recognise their true identities, had not unexpected barcoding results drawn attention to them.
Five species of the Pristiphora depressa species group are now recorded in Germany. This is a remarkable increase, considering that only two of them were included in the checklist by Blank et al. (2001). On the other hand, many gaps exist in our knowledge of these species. Four of them are known only from specimens of a single sex and, because of previous taxonomic confusion, we also know little or nothing about their host plant ranges or biology. Although adults of most species are clearly associated with Acer species, which are certainly the main (or only?) host plants, few larvae have yet been reared or identified by DNA sequencing. Most previous studies have tended to name only single Acer species as hosts of Pristiphora depressa group species. This is at least partly caused by lack of data and probably gives a false impression of a greater degree of monophagy in these species than really exists. For example, Liston and Späth (2008) indicated that only Acer campestre is a host of Pristiphora subbifida, whereas Stankevičienė and Šabūnaitė (2016) identified four distantly-related Acer species as its hosts in Kaunas Botanical Garden, Lithuania. As the geographic range of P. tetrica and P. melagonia in Europe is not congruent with that of any single European Acer species, we conclude that they must also use more than one species of Acer as hosts. Perhaps more important than host specificity in understanding the diversity of the group, is the synchronisation of the sawfly species' phenology with that of its host, as discussed for P. tetrica and P. cretica by Liston et al. (2015). At present, CO1 barcoding, using the standard barcode region of the animal kingdom (Hebert et al. 2003), clearly separates the known West Palaearctic species of the depressa group, so that it should be rather easy to gain improved data on their host plant ranges.