Laboulbeniales (Ascomycetes) from Latvia

This contribution presents new and historical data on the Laboulbeniales of Latvian Coleoptera. An annotated checklist of 26 taxa is given, 13 are new for Latvia. Only six taxa (accepted names) from Briedis’ historical list were found again and six more need to be conﬁrmed as Briedis’ material was lost. A neotype is indicated here for the extremely rare Laboulbenia elaphricola Siemaszko et Siemaszko. Its morphology is discussed and compared with Laboulbenia elaphri Spegazzini and Laboulbenia vulgaris Peyr.


INTRODUCTION
Laboulbeniales (Ascomycetes) are strictly parasitic on Arthropoda, mainly insects. Although widespread, information concerning their distribution in Europe is unequal and, as yet, a reflection of the distribution of laboulbeniologists in Europe (We i r , Ro s s i 1995). The most exhaustive studies were carried out in Spain and Poland, followed by France, Finland, Britain, Italy, Belgium, Germany and Hungary. From other European countries, including the Baltic countries, only very few and isolated reports or collections are available. Records from Estonia and Lithuania have been published in S i e m a s z k o and S i e m a s z k o (1928,1932), H u l d é n (1985) and M a r k o v s k a j a (2000) respectively. In Latvia 16 species of Laboulbeniales have been recorded in the literature (B r i e d i s 1932; H u l d é n 1985). All species were found on ground beetles (Coleoptera, Carabidae) and all, but one Misgomyces, belong to Laboulbenia. A thorough study of Briedis' material and notes was not possible as it could not be located; we consider it lost.

MATERIALS AND METHODS
Carabidae and Staphylinidae (Coleoptera) were captured by hand or by means of pitfall traps. Sampling sites are situated in Latvia and mainly include river associated forests, riverine marshes and banks along the river Gauja and Abuls (Valmiera raijons). Samples were also taken in the plant debris zones along the shorelines of the Baltic Sea, near Jurmala (Majori) and Pabazi (Balta Kapa). Hosts were killed and stored in 70 or 90% denaturated ethanol. Screening hosts for infections and preparing of thalli was done using a stereomicroscope at high magnification (25-50x). The thalli were mounted and stained in permanent slides using a medium based on Arabic gum with cotton blue and a trace of glycerine (D e K e s e l 1998). Field data (locality, GPS-coordinates, date and habitat), host data (taxon, gender and infection site) and parasite data (taxon, number of specimens and development) were recorded. Slide(s) from the Laboulbeniales and the corresponding hosts were given the same number (i.e. DKK-number); all material and notes are deposited at BR (Herbarium National Botanic Garden of Belgium). When specific identity of a host was doubtful only the generic name of the host was used, followed by sp. The generic taxonomy of Staphylinidae follows L o h s e (1964) and L o h s e et al. (1974), for Carabidae L i n d r o t h (1974) or Fr e u d e (1976).
Nomenclature and identification of all Laboulbeniales found in Latvia is largely based on 'The Laboulbeniales of Poland' by T. M a j e w s k i (1994). We consider it a key reference work for the study of the Laboulbeniales from the Baltics. To avoid redundancy we refrained from giving exhaustive species descriptions and comments, unless complementary to the information given in M a j e w s k i (l.c.) or elsewhere.

RESULTS
Annotated and preliminary checklist of the Laboulbeniales from Latvia In the following checklist we placed species in bold when they correspond with verified records, i.e. species found by us in [2004][2005] Fig. 2). It was found in Eastern Poland, Pulawy, on Elaphrus riparius L. The original description is very short and the drawing of the type represents a damaged and incomplete outer appendage. The type material was unfortunately lost during WWII (M a j e w s k i 1994). Since its description only B à n h e g y i (1950) reported L. elaphricola, but stated later that his material belongs to L. elaphri (B à n h e g y i 1964). L. elaphricola seems to be a very rare species, because very intensive screening of suitable habitats in Eastern Poland, Bialowieza (M a j e w s k i 2003) did not supply new material. Today it is a species with an uncertain status. In the absence of information on its full morphology and eventual posi-tion related variations, B à n h e g y i (1964) and M a j e w s k i (1994) suggested that it could just be a growth form of the more common Laboulbenia elaphri Spegazzini.
The numerous specimens we could collect on Elaphrus riparius from Latvia correspond with L. elaphricola. Our material confirms that this species is not a growth form of L. elaphri as its typical short and stout thalli occur invariably on different parts of the hosts' integument. L. elaphricola is indeed a small and dark species and no forms, even closely resembling L. elaphri, were seen on the studied hosts. We consider S i e m a s z k o and S i e m a s z k o ' s L. elaphricola a good species. It is very distinct from L. elaphri and actually close to L. vulgaris, as already stated by S i em a s z k o and S i e m a s z k o (1928). The following diagnosis and figure 1 should help to separate it from L. vulgaris.
-All thalli of L. elaphricola are small and stout, invariably of their origin on the host. They are never longer than 220μm (foot-ostiolum).
-Already in an early stage of development L. elaphricola shows a deep pigmentation of the receptaculum. Except for the poorly and uniformly pigmented cell I, cell II and septum I-II, all adult specimens have a deeply pigmented to blackish thallus. In L. vulgaris the septum I-II is often darker, a feature that lacks in L. elaphricola.
-The perithecium is more free in L. elaphricola than in L. vulgaris, i.e. the insertion cell and cell V always being slightly below the middle of the perithecium in L. elaphricola.
-Cell II of L. elaphricola almost immediately widens upwards, forming a strikingly long septum with cell VI and a short septum with cell III. Cell VI is much broader than high. In most cases the septum II-VI is at least twice the length of septum II-III.
-The upper receptacle, i.e. the complex of cells III, IV and V, is delimited or demarcated from the rest of the thallus by a very deeply pigmented line, even in very young thalli. This darkened line starts at the anterior side of the insertion cell (close to the perithecium). It continues downwards along the adaxial septa of cell V, cell IV and cell III, makes a curves along the basal septum of the latter, to finally end at the posterior (dorsal) side of the receptacle.
-The outer appendage is not branched and relatively long. In many cases, but not always, the three basal cells of the outer appendage tend to be slightly inflated.
Specimens with a branched outer appendage occur very rarely and only as a result of damage and subsequent atypical regeneration of the appendage. The inner appendage is branched once or twice and never exceeding the ostiolum.
-The insertion cell is constricted, sometimes strongly. The name bearing type material of L. elaphricola is lost and since its description L. elaphricola was not found again in Poland or elsewhere (Majewski pers. comm.  Thallus very slender, hyaline to yellowish, up to 390 μm long. Receptaculum slender, 210 μm high. Cell I and II three to four times higher than broad, without pigmentation. Base of cell I not pigmented; foot hyaline, with one or two small brownish spots. Cell III and IV about the same height (20-25 μm), two times higher than broad. Adaxial side of cell V free from the perithecium. Cell V triangular, slightly rounded, half as high as cell IV. Insertion cell amber to dark brown, moderately constricted. Abaxial (outer) appendage straight, not branched, up to 80 μm long, probably longer in undamaged specimens, not pigmented and without dark septa; parafysopodium (basal cell of outer appendage) similar to other cells, up to 20 μm high. Adaxial (inner) appendage hardly pigmented, up to 80μm long; andropodium up to 8μm long, bearing two simple appendages. Antheridia not seen. Cell VI smaller than cell III, easily distinguished as is the rest of the perithecial basal cells. Perithecium long, slender and slightly asymmetrically curved, 180 × 32 μm, widest below the middle, hyaline, without or almost without pigmentation at the abaxial side; perithecial apex is differentiated in a 70 μm long and slender abaxially bent neck. Ostiolum hyaline, consisting of 4 strongly inflated cells (lips), the most adaxial cell (lip) up to 20μm shorter than the others.
Laboulbenia luxurians Thaxt.   (1932) The species listed below represent historical records from B r i e d i s (1932). All these taxa were either reduced into synonymy (S a n t a m a r i a et al. 1991 or M a j e ws k i 1994) or should be considered as doubtful records in the studied area. • On Agonum assimile (as Platynus assimilis Payk.), near Valka 7. Laboulbenia polyphaga Thaxt., i.e. var. calathicola probably to be considered a record of L. calathi CONCLUSIONS -Twenty six species are reported for Latvia, 13 are new for the studied territory. -Six species reported by B r i e d i s (1932) were confirmed.
-The presence of six more species, reported by B r i e d i s (1932) and H u l d é n (1985), needs to be confirmed with new material as Briedis' original material from Latvia is untraceable.
-Laboulbenia elaphricola Siemaszko et Siemaszko is reported for Latvia. This taxon is extremely rare and not reported, with certainty, since its discovery. It has an uncertain status because of a very short original diagnosis. The name bearing type was unfortunately lost and L. elaphricola is currently considered a growth form of L. elaphri. The Latvian material, however, provides enough evidence that L. elaphricola is a good species.