Stigmatomyces divergatus Thaxt.

Santamaria, Sergi & Pedersen, Jan, 2021, Laboulbeniomycetes (Fungi, Ascomycota) of Denmark, European Journal of Taxonomy 781, pp. 1-425 : 256-258

Stigmatomyces divergatus Thaxt.

MB#263386

Figs 57G–K , 106B

Memoirs of the American Academy of Arts and Sciences 16: 122 ( Thaxter 1931). –

Type: “ On the superior tip of the abdomen of Leptocera sp. , No. 3479 , Fort de Kock , Sumatra ”; FH.

Stigmatomyces chthonicus Huldén ( Huldén 1983: 65) [MB#108564]

Stigmatomyces subterraneus Huldén ( Huldén 1983: 68) [MB#108570]

Diagnostic features

Basal cell of appendage slightly darker, supporting a series of 3–10 flattened, oblique, dorsally almost inflated cells, each giving rise to rather elongated antheridia on the inner margin. Perithecium with an oval venter, showing distal knobs below the neck ( Fig. 57K ) and a well-distinguished, slightly bent, gradually tapering neck ending in a distinct, asymmetrical tip which shows two protruding lips. [Detailed descriptions: Majewski 1994b – as S. chthonicus and S. subterraneus –; De Kesel & Hanssens 2007]

Distribution and hosts

Reported from Indonesia (type), USA ( Rossi et al. 2013), and some European countries like Finland ( Huldén 1983, as S. chthonicus and S. subterraneus ), Poland ( Majewski 1990a, 1990b as S. subterraneus and S. chthonicus , respectively), Spain ( Santamaria & Rossi 1993), Belgium ( De Kesel & Hanssens 2007), and Portugal ( Rossi et al. 2013). Occurs on Leptocera , Spelobia , Apteromyia , and Limosina ( Diptera Sphaeroceridae ).

Collections examined from Denmark

On Spelobia clunipes (Meigen, 1830) ( Diptera Sphaeroceridae ) DENMARK – Nordøstsjaelland (NEZ) • Stampeskov ved Rådvad ; 55°48.332′ N, 12°33.138′ E; UB48; 14 Apr. 2013; JP 1191; W. Gritsch det.; ZMUC C-F-123715 . – Sydsjaelland (SZ) • Gammel Dyrehave ved Edelesminde ; 55°16.930′ N, 11°58.348′ E; PG83; 27 Nov. 2016; JP 1192; W. Gritsch det.; ZMUC C-F-123716 • Haslev ; 55°19.669′ N, 11°58.206′ E; PG83; 19 Jun. 2016; JP 1190; W. Gritsch det.; ZMUC C-F-123714 .

On Spelobia luteilabris (Rondani, 1880) ( Diptera Sphaeroceridae ) DENMARK – Fyn (F) • Skovsgårds Mølle ; 54°50.339′ N, 10°44.594′ E; PF17; 5 Oct. 2016; JP 1195; W. Gritsch det.; ZMUC C-F-123719 .

On Spelobia palmata (Richards, 1927) / talparum (Richards, 1927) ( Diptera Sphaeroceridae ) DENMARK – Nordøstsjaelland (NEZ) • Indelukket ved Frederiksborg Slot ; 55°56.191′ N, 12°17.861′ E; UC30; 19 Mar. 2017; JP 1194; W. Gritsch det.; ZMUC C-F-123718 . – Sydsjaelland (SZ) • Gammel Dyrehave ved Edelesminde ; 55°16.930′ N, 11°58.348′ E; PG83; 27 Nov. 2016; JP 1193; W. Gritsch det.; ZMUC C-F-123717 .

On Spelobia sp. ( Diptera Sphaeroceridae ) DENMARK – Østjylland (EJ) • Kjellerup ; 56°17.644′ N, 9°25.850′ E; NH23; 16 Feb. 2018; JP 1196; W. Gritsch det.; ZMUC C-F-123720 .

Remarks

First record from Denmark. This species may be difficult to distinguish from S. crassicollis in the absence of the four knobs on the perithecial venter as in S. divergatus .

Figures

Fig. 57. Stigmatomyces spp. A–F. S. crassicollis Thaxt. A–D. Mature thalli, from Leptocera fontinalis (A–B), from Spelobia luteilabris (C), and from Spelobia rufilabris (D). E–F. Primary appendages in detail. – G–K. S. divergatus Thaxt. G–I. Mature thalli. J. Primary appendage in detail. K. Perithecial tip in detail. Scale bars: 50 µm. Photographs from slides ZMUC C-F-124097 (A, E), ZMUC C-F-124017 (B, F), ZMUC C-F-124018 (C), ZMUC C-F-124019 (D), ZMUC C-F-123720 (G–H, J–K), ZMUC C-F- 123717 (I).

Fig. 106. Habitus of hosts with fungi. Some thalli are zoomed in, and others are encircled.A. Corylophus cassidoides with four thalli of Laboulbenia corylophi on the apex of the elytra. B. Spelobia palmata with three thalli of Stigmatomyces divergatus on the left middle coxa. Scale bars: 1 mm. (Photos: Aslak Kappel Hansen).