Stephanopachys linearis (Kugelann, 1792) is formally protected at EU level, being listed in Annex II of the Habitats Directive (cf. Brustel et al. 2013; Trizzino et al. 2013). Its presence in Italy was considered doubtful (cf. Audisio et al. 1995; Trizzino et al. 2013; Genovesi et al. 2014; Nardi et al. 2014, 2015; Audisio et al. 2015), since based only on an old literature record from South Tyrol. In reality, this literature record refers to a congeneric species (see further on), so the aim of this paper is to provide the first true Italian records of S. linearis.
Material and methods
The beetles were identified following the works of Borowski & Węgrzynowicz (2012), McCaffrey (2012) and Brustel et al. (2013). The distribution pattern of the species is expressed also by a chorotype, following Vigna Taglianti et al. (1999). The conservation status of this species in Italy was evaluated according to IUCN (2014). The botanical systematics and nomenclature follow The Plant List (2013). Interpolations are given in square brackets. The following abbreviations are used in the text: ex = specimen/s; tff = translation from French; tfg = translation from German; tfi = translation from Italian.
Acronyms of specimen depositories:
F. Angelini collection, c/o Museo di Storia Naturale, Sezione di Zoologia “La Specola”, Università degli Studi di Firenze, Florence, Italy
P. Luigioni collection, c/o Museo Civico di Zoologia, Rome, Italy
Museo Civico di Storia Naturale, Genoa, Italy (R. Poggi, pers. comm., 2016)
Material examined. Italy: Friuli [(Udine)], Carnia, Tolmezzo, XI.37, A. Falzoni [leg.], ex coll. Fiori [= former collection Fiori], 2 ex (MCSG); [(Udine), Carnia], Tolmezzo, XI.1937, unknown collector, 1 ex (CFA).
Chorotype and distribution. Sibero-European (boreo-alpine in Europe). This species occurs in: Armenia, Austria, Azerbaijan, Belarus, NE China (Heilongjiang), Denmark, Estonia, Finland, France (Corsica, Hautes-Alpes, Pyré- nées-Orientales), Georgia, Germany, NE Italy (mainland), Iran, Latvia, Lithuania, Mongolia, Norway, Poland, Czech Republic, Russia (Central European Territory, Northern European Territory, West Siberia, East Siberia, Far East), Slovenia, Sweden, Switzerland and Ukraine (cf. Sainte-claire Deville 1902; Lesne 1903, 1909; Sainte-Claire Deville 1910; Lundberg 1995; Köhler & Klausnitzer 1998; Nardi 2004; Borowski 2007; Brustel et al. 2013; Müller et al. 2013; Brustel 2014; Brustel & Aberlenc 2014; Ranius et al. 2014; Audisio et al. 2015; Liu et al. 2016). According to Borowski & Węgrzynowicz (2007), this species may be introduced with timber into various regions of the world, but it needs of low temperature for its development, so its acclimatization in warm countries is improbable.
Ecology. Stephanopachys linearis develops on coniferous trees, usually damaged by fire but still living; all host plants belong to the family Pinaceae: Abies alba Mill., Larix europaea DC. (= L. decidua Mill.), L. gmelinii (Rupr.) Kuzen., Picea abies (L.) H.Karst., and Pinus sylvestris L. (cf. Lesne 1901, as S. elongatus Paykull; Simon 1952, as S. elongatus Payk.; Geis 2002; Johansson et al. 2011; Borowski & Węgrzynowicz 2012; Brustel et al. 2013; Ranius et al. 2014; Liu et al. 2016). The larvae of the Stephanopachys species are specialized feeders on gymnosperms (Liu et al. 2008); nevertheless, those of S. linearis may exceptionally feed also in old Quercus wood (Koch 1992). Asmuss (1836, as Apate elongata Payk.) recorded a specimen of this species in Estonia, together with a specimen of S. substriatus (Paykull, 1800) in an opening on a Sorbus domestica L. tree (Rosaceae); this record is very probably accidental and this tree has since never been recorded as a host of these beetles.
Notes. Tyrol is a historical region of Eastern Alps, now split between Western Austria and Northern Italy (South Tyrol). Stephanopachys linearis was not recorded from Tyrol by Gredler (1866), who recorded only the closely related S. substriatus from a site of South Tyrol (Gredler 1866: 265, as Dinoderus substriatus Payk.). In spite of this, some subsequent authors included Tyrol in the distribution of S. linearis, attributing these records to Gredler as follows:
“according to Gredler in Tyrol [tfg]” (Kiesenwetter 1877: 31, as D. elongatus);
“and from Tyrol (Gredler sec. [= according to] Kiesenwetter [(1877)]. These indications need to be confirmed [tff]” (Lesne 1897: 335, footnote, as S. elongatus Paykull);
“Tyrol (Gredler sec. [= according to] Kiesenwetter [(1877)]” (Lesne 1901: 92, as S. elongatus Paykull);
“Hamburg, Styria and Tyrol [tfg]” (Schilsky 1899: XXX-VI. 99);
“species that is known to occur in Tyrol and Corsica [tff]” (Lesne 1909: 103, as S. linearis Kug.);
“St [= Styria (Brancsik, Grimmer, Kodermann, R. Weber)] Ti [= Tyrol (Gredler, Halbherr, Rosenhauer)] Ha [= Hamburg (Endrulat and Tessin, Koltze, Preller, v. Sydow, Wimmel)] Pr [= Prussia (East- and West Prussia) (Lentz, Vorbringer)] [tfg]” (Schilsky 1909: 115, as S. elongatus Payk.);
“Tyrol [tfi]” (Porta 1929: 413, as S. elongatus Payk.);
640, as S. elongatus Payk.), S. linearis was never recorded from South Tyrol or Tyrol.
Horion (1961), as mentioned above, attributed records of S. linearis from South Tyrol to Gredler (1866) and Porta (1929), but this is an error (see also Di Santo & Biscaccianti 2004: 105) since these two authors (see above) did not mention S. linearis from this region. Also later, this species was never reported from South Tyrol (cf. Peez & Kahlen 1977; Kahlen 1987; Kahlen et al. 1994; Kahlen & Hellrigl 1996). Paill (2005) was also in error in attributing a record of S. linearis from South Tyrol to Schilsky (1909) (see above), who recorded this species only from Tyrol (see above).
The above-listed erroneous records for South Tyrol were the source of the subsequent doubtful citations of S.linearis for Italy (cf. Audisio et al. 1995; Nardi 2004, 2005, 2007; Trizzino et al. 2013; Genovesi et al. 2014; Nardi et al. 2014; Audisio et al. 2015; Nardi et al. 2015). Borowski (2007) also recorded this species for Italy (without further data), but his record was probably based on those of Horion (1961).
In this framework, Stephanopachys linearis was ultimately considered absent in Italy and it was not included in the recent Italian handbook on animal species of Community Interest (Stoch & Genovesi 2016). However, based on the above, recently examined specimens from Friuli (NE Italy), this species must be added to the Italian fauna.
Stephanopachys linearis is unrecorded from Slovenia (Borowski 2007; Vrezec et al. 2011), but its Italian record suggests that, as its close relative S. substriatus, it could occur in the neighbouring Slovenian conifer forests (cf. Jurc et al. 2008; Podlesnik & Jurc 2012).
Moreover, recent records from SE France by Brustel et al. (2013) report the presence of this species in SW Alps, in a mountain area (Hautes Alpes, upper portion of the Guil river valley) just a few kilometers west of the Pellice Valley, NW Italy (Piedmont, Torino Province, Bobbio Pellice municipality).
In the IUCN Red List of European saproxylic beetles (Nieto & Alexander 2010), S. linearis is classified as “Least concern”, whereas in the Italian Red Lists its status was initially indicated as “Vulnerable” (Bologna 2005; Nardi 2005, 2007) and later as “Endangered” (Nardi et al. 2014, 2015). S. linearis is thus far known in Italy only from the above cited locality in Friuli (Tolmezzo), but absence of recent data and of specialized research aimed to collect again the species in this area suggests us to tentatively evaluate it as “Data Deficient (DD)” at Italian regional scale. However, when collected again in the next future in the same locality only, S. linearis could be probably considered at the same regional scale as “Critically Endangered (CR)” following the IUCN criteria B1ab(i,ii,iv) (IUCN 2014).
The area of Tolmezzo includes mountain conifer forests where some of the known host trees of S. linearis occur (cf. Gasparini & Tabacchi 2011; Nimis et al. 2013). Some of these forests are included in the EU Habitats Directive (cf. Poldini et al. 2006; Biondi et al. 2009; Angelini et al. 2016), and the locality of collection is near some protected areas (Musi 2005; Regione Autonoma Friuli-Venezia Giulia 2015; http://www.parks.it/regione.friuli.venezia. giulia/map.php?prov=UD). All of these factors combined have probably allowed the local survival of the species, but this needs to be confirmed by an adequate field survey using the methods (direct collecting, light traps, intercept traps, ex situ emergence traps) usually adopted in the monitoring of the closely related S. substriatus and other saproxylic Bostrichidae (cf. Mairhuber & Paill 2005; Paill 2005; Brustel et al. 2013; Trizzino et al. 2013; Redolfi De Zan et al. 2014; Macagno et al. 2015; Mifsud & Nardi 2016; Nardi et al. 2016).