Chaetarthriomyces spiralis Santam.

MB#474853

Fig. 22C–D

Nova Hedwigia 72 (3–4): 379 (Santamaria 2001a). –

Type: “ Spain. Jaén: Santiago–Pontones, Parque Natural de Cazorla, Segura y Las Villas, río Aguamulas, below the head of Chaetarthria seminulum (Herbst) ( Coleoptera, Hydrophilidae), 12.V.1990, leg. S. Santamaria, BCB–Mycotheca SS·0945 [Holotypus]”; BCB.

Diagnostic features

Primary appendage strongly arcuate, consisting of up to 12 isodiametric cells culminated with a rounded uppermost cell. Perithecium with a blunt apex, with the wall cells spirally arranged and distinctively brown-pigmented (Fig. 22D). [Detailed description: Santamaria 2003]

Distribution and hosts

Grows on the underside of the head of Chaetarthria (Col. Hydrophilidae) in Spain (type) and Poland (Majewski 2008).

Collections examined from Denmark

On Chaetarthria seminulum (Herbst, 1787) (Col. Hydrophilidae)

DENMARK – Nordvestsjaelland (NWZ) • Flyndersø ved Dybesø; 55°58.151′ N, 11°45.621′ E; PH60; 4 Nov. 2017; JP 722; JP det.; ZMUC C-F-123214 .

Remarks

First record from Denmark. This species is much larger and significantly less frequent than C. crassiappendicatus . The development of two viable perithecia on the same thallus is exceptional (Fig. 22D).