Laboulbenia ophoni Thaxt.

Santamaria, Sergi & Pedersen, Jan, 2021, Laboulbeniomycetes (Fungi, Ascomycota) of Denmark, European Journal of Taxonomy 781, pp. 1-425 : 186-189

Laboulbenia ophoni Thaxt.

MB#236083

Fig. 39D–G

Proceedings of the American Academy of Arts and Sciences 35: 190 ( Thaxter 1899). –

Type: “ On Harpalus sulphuripes Germ. from Italy ”; FH. [type according to Majewski 2008]

Diagnostic features

Thallus pale yellowish brown. Cell V oval, similar in length to cell IV, connected with septum III–IV ( Fig. 39D–F ) or, very rarely, short and then not connected ( Fig. 39G ). Outer appendage once or twice divided from the suprabasal cell. Inner appendage consisting of a basal cell bearing one to several branches terminated by clustered antheridia ( Fig. 39F ). Basal cell of inner appendage half as long than basal cell of outer appendage. Perithecium with two preostiolar spots merged in a contrasting black ring. [Detailed descriptions: Thaxter 1908; Majewski 1994b; Santamaria 1998]

Distribution and hosts

The typical hosts belong to Col. Carabidae of the genera Ophonus , Carterus Dejean & Boisduval, 1829 and Harpalus , but this fungus has been also reported on Amara , Dolichus Bonelli, 1810 , Scybalicus Schaum, 1862 , Europhilus Chaudoir, 1859 and Agonum ( Majewski 2008) . Known from Europe: Finland, France, Germany, Hungary, Italy, Poland, Romania, Spain, Sweden, Switzerland, Russia ( Santamaria et al. 1991), United Kingdom ( Cannon et al. 1985), Belgium ( De Kesel 1998), Lithuania ( Markovskaja 2000), Sweden ( Huggert 2010), and Slovakia ( Rossi et al. 2010). Also in North Africa from Algeria ( Thaxter 1899).

Collections examined from Denmark

On Amara apricaria (Paykull, 1790) (Col. Carabidae ) DENMARK – Nordøstsjaelland (NEZ) • Botanisk Have i København ; 55°41.214′ N, 12°34.289′ E; UB47; 18–25 Jul. 2013; JP & O. Karsholt 297; JP det.; ZMUC C-F-122776 .

On Harpalus affinis (Schrank, 1781) (Col. Carabidae ) DENMARK – Nordøstsjaelland (NEZ) • Brønshøj ; 55°42.234′ N, 12°30.135′ E; UB47; 18 Aug. 2018; JP 1170; JP det.; ZMUC C-F-123695 .

On Harpalus rubripes (Duftschmid, 1812) (Col. Carabidae ) DENMARK – Sydsjaelland (SZ) • Klinteby Klint ; 55°11.579′ N, 11°32.489′ E; PG61; 19 Apr. 2015; H. Liljehult 27; JP det.; ZMUC C-F-122500 .

On Ophonus melletii (Heer, 1837) (Col. Carabidae ) DENMARK – Fyn (F) • Gyldenstens inddaemmede Strand ; 55°34.447′ N, 10°7.211′ E; NG75; 2 Apr. 2014; JP 700; JP det.; ZMUC C-F-123189 .

On Ophonus puncticeps Stephens, 1828 (Col. Carabidae ) DENMARK – Lolland, Falster, Møn (LFM) • Rødbyhavn ; 54°39.569′ N, 11°21.958′ E; PF55; 18 Aug. 2018; JP 1171; JP det.; ZMUC C-F-123696 .

On Ophonus rufibarbis (Fabricius, 1792) (Col. Carabidae ) DENMARK – Lolland, Falster, Møn (LFM) • Jydelejet, Møns Klint ; 54°59.171′ N, 12°31.954′ E; UA49; 12 May 2018; J. Kypke et al. Dry0049; JP det.; ZMUC C-F-124115 • Vest for Bandholm ; 54°50.303′ N, 11°28.050′ E; PF57; 3 Jan. 2019; JP 1316; JP det.; ZMUC C-F-123852 .

On Ophonus rupicola (Sturm, 1818) (Col. Carabidae ) DENMARK – Sydsjaelland (SZ) • Klinteby Klint ; 55°11,579′ N, 11 32,489′ E; PG61; 19 Apr. 2015; H. Liljehult 26; JP det.; ZMUC C-F-122499 .

Other material examined

Lectotype of Laboulbenia polyphaga (here designated) (MycoBank MBT10002233 ) UNITED STATES • “ Laboulbenia polyphaga , slide from FH, #8460, barcode 00313730, “type”, on Olisthopus parmatus Say. , from York , Maine, York County ( USA), 29–06–1892 ”; lectotype: FH[00313730] (here designated) (MycoBank MBT10002233 ). [consists of six mature thalli in poor condition. ( Fig. 39C )]

Remarks

First record from Denmark. In species of the genus Laboulbenia the trait “septum IV–V connected with septum III–IV” versus “… not connected…” is considered mostly invariable and exclusive, and exceptions to this rule have rarely been documented. However, L. ophoni is one of these species, where in some, but not all specimens septum IV–V does not reach septum III–IV.

Thalli we have found on Amara apricaria [C-F-122777] are relevant for this discussion. The species of Laboulbenia reported on Amara are: L. aubryi , L. flagellata , L. polyphaga , and L. ophoni . The latter was reported on Amara by Weir (1996) from Great Britain and by Rossi et al. (2010) from Slovakia, although in the latter case with the reservation of “to be confirmed” because of the variability observed in septum IV–V. Danish thalli on Amara agree with Slovakian thalli and also vary in this feature but the remaining characters fit very well with the description of typical L. ophoni ( Fig. 39G ).

Of the three remaining species found on Amara , L. polyphaga deserves our special attention because it is significant to the discussion of L. ophoni . The status and distinctiveness of L. polyphaga is a real headache. Laboulbenia polyphaga was loosely described by Thaxter (1893, 1896) who wrote: “this form, although presenting no striking peculiarities of structure, seems sufficiently well defined to warrant its separation as a distinct species”. Furthermore, Thaxter added the sentence “it is nearly allied to L. pterostichi ”, which indeed is highly surprising, even shocking. Thaxter described L. polyphaga from a very diverse material without specifying a type, i.e., on Olisthopus , Stenolophus (including Agonoderus , sometimes treated as a separate genus), Badister , Harpalus , Bradycellus , and Amara . Over the years, the list of records and hosts for L. polyphaga increased significantly, becoming absolutely overwhelming ( Santamaria et al. 1991; Majewski 2008). Balazuc (1974e) also wrote an extensive explanation about the confusion concerning this taxon. Lastly, Majewski (1994b) related this species with others having simple outer appendage like L. benjaminii , L. notiophili (as L. casnoniae ), and L. eubradycelli , and suggested the possibility of a collective species. Although some Polish thalli on Amara show an outer appendage once divided above the second cell, Majewski (1994b) classified his thalli from Amara and Trichotichnus Morawitz, 1863 as L. polyphaga in line with other records ( Bánhegyi 1940; Balazuc 1974e; Sugiyama 1973; De Kesel & Rammeloo 1992), defining its own characteristics in contradiction to some parts of Thaxter’s description but accepting others like that where a ± copiously branched appendage is mentioned. Majewski’s Polish and our Danish thalli on Amara are identical.

Trying to solve this confusion, we decided to request from FH the loan of Thaxter’s original slides (see above under other material examined). According to curatorial staff in that herbarium, only one slide labelled as the “ type ” of L. polyphaga exists. Probably remaining material published by Thaxter has not been registered under the name L. polyphaga . One explanation we can think of is that Thaxter was not absolutely convinced about its determination and never labelled his slides as L. polyphaga , so that these are difficult to find in FH databases. With the single slide received, we decided for the lectotypification of L. polyphaga because some of the included thalli seem to be the same as those illustrated by Thaxter (1896: pl. XV, figs 18–21), especially that of fig. 18 which is similar to, if not the very same that we have photographed from the borrowed slide ( Fig. 39C ).

In conclusion, we suggest that L. polyphaga should be restricted to thalli growing on Olisthopus , with dark brown thalli, unbranched outer appendage, inner appendage bearing a tuft of few antheridia lacking sterile branches, and a small, bright coloured cell V, located in the inner-upper corner of cell IV and separated from this by an oblique septum not reaching the septum III–IV. For comparison of these thalli with L. olisthopi , also on Olisthopus , refer above to the proper paragraph of this species.

Figures

Fig. 39. Laboulbenia spp. A–B. L. oodiphila Huldén. Mature thalli. – C. L. polyphaga Thaxt. Broken mature thallus from type slide kept in FH, collected on Olisthopus parmatus. – D–G. L. ophoni Thaxt. D–E. Mature thalli from Harpalus and Ophonus, respectively. F. Immature thallus showing appendages in detail and labelled basal cell of inner appendage (bc ia). G. Mature thallus from Amara apricaria. Scale bars: 50 µm. Photographs from slides ZMUC C-F-124118 (A–B), FH8460 (C) (lectotype), ZMUC C-F-122500 (D), ZMUC C-F-124115 (E–F), ZMUC C-F-122776 (G).