Chitonomyces elongatus Speg.

Santamaria, Sergi & Pedersen, Jan, 2021, Laboulbeniomycetes (Fungi, Ascomycota) of Denmark, European Journal of Taxonomy 781, pp. 1-425 : 101

Chitonomyces elongatus Speg.

MB#163977

Fig. 20E–F

Anales del Museo Nacional de Historia Natural de Buenos Aires 27: 44 ( Spegazzini 1915b). –

Type: “Conegliano, on Laccophilus poecilus (as L. virescens ), VII.1914, slide C. Spegazzini 46–1915 ( LPS–61915 , type)”; LPS. [according to Santamaria 2001b: 345] [ Italy]

Diagnostic features

Dimorphic. Thalli on female hosts ( Fig. 20E ) are zigzagged, with cell I up to seven times as long as broad; cell Ia similar to I, abruptly turning back; cell IIIa laterally diverging from the perithecial axis. Thalli on male hosts ( Fig. 20F ) are straight, with cell I up to ten times as long as broad; cell Ia trapezoidal, ± isodiametric; cell IIIa 2–3 times as long as broad, distinctly darker than the surrounding cells. [Detailed descriptions: Santamaria 2001b, 2003]

Distribution and hosts

This species can be seen only thanks to the translucency of last abdominal sternite of its hosts, where the brownish thalli and their darkened feet can be distinguished; otherwise they would be invisible because they are nearly hidden from eye, with only the upper parts being slightly perceptible sometimes. On Laccophilus (Col. Dytiscidae ) from Italy (type), USA? ( Seymour 1967, this record should be verified), and Spain ( Santamaria 2001b).

Collections examined from Denmark

On Laccophilus minutus (Linnaeus, 1758) (Col. Dytiscidae )

DENMARK – Vestjylland (WJ) • Simmelmose ; 55°46.299′ N, 9°3.519′ E; NG08; 2 Jun. 2019; JP 1478; JP det.; ZMUC C-F-124060 , C-F-124061 .

Remarks

First record from Denmark. Spegazzini (1915b) only described the form found on female hosts, without specifying its origin, mentioning the thorax as its growing location and Laccophilus poecilus as the host; all is quite doubtful.

Figures

Fig. 20. Chitonomyces spp. A–B. C. aculeifer Speg. Mature thalli with labelling of cells and other parts of the thallus, i.e., cells I, Ia, II, IIa, III, IIIa, VI, antheridium (an), primary appendage (pa) and perithecial outgrowth (arrow). A. From Graptodytes. B. From Haliplus. –C–D. C. bidessarius (Thaxt.) Thaxt. Mature thalli with labelling of cells of the thallus, i.e., cells I, Ia, II, IIa, III, and IIIa. – E–F. C. elongatus Speg. E. Thallus from a female host. F. Thallus from a male host. – G. C. ensifer Speg. Mature thallus showing prominent cell VI and perithecial outgrowth (arrow). Scale bars: 50 µm. Photographs from slides ZMUC C-F-123553 (A), ZMUC C-F-124083 (B), ZMUC C-F-122816 (C–D), ZMUC C-F-124060 (E), ZMUC C-F-124061 (F), ZMUC C-F-123670 (G).