Observations on the Genus Psammina, Including the Description of Two New Algicolous and Lichenicolous Species

Abstract

Psammina inflata Earland-Bennett & D. Hawksw. and P. simplex Earland-Bennett & D. Hawksw. are described as new species from coccoid green algae and crustose or leprose lichens in lowland Britain. Additional records and hosts for P. stipitata are reported, and a key to the four species now known in the British Isles is presented. Psammina simplex is the more strongly pathogenic of the species, eventually destroying its hosts. The discovery of these new species adds weight to the view that the genus is more appropriately regarded as a hyphomycete rather than an acervular coelomycete. The size, shape and septation dimensions of the conidial arms were found to be the most reliable characters for species separations in the genus. Pycnopsammina lobariae Diederich & Etayo is also cited from the British Isles for the first time.

A newPsamminaspecies with exceptionally long conidial arms, with a key to the ten known species of the genus

“…2). The dimensions of the conidial arms of P. stipitata thus overlap with the dimensions of those originally reported for P. simplex , (7–)15–25(–29) × (1.5–)2–4 μm (Earland-Bennett & Hawksworth 1999). The number of septa in the conidial arms was originally described as the main difference between P. stipitata and P. simplex , but later Earland-Bennett & Hawksworth (2005) considered that feature less reliable.…”

“…Psammina inflata, characterized by the short and inflated conidial arms, was originally described from the UK (Earland-Bennett & Hawksworth 1999), and has also been reported from France (Roux et al 2018), Germany (Eichler et al 2010a) and Luxembourg (Eichler et al 2010b). We now report it also from three localities in the Netherlands (Figs 2 & 4).…”

“…Psammina inflata , characterized by the short and inflated conidial arms, was originally described from the UK (Earland-Bennett & Hawksworth 1999), and has also been reported from France (Roux et al . 2018), Germany (Eichler et al .…”

The first lichen-forming species of Psammina, P. palmata sp. nov., with notes on the status of Cheiromycina and Pycnopsammina

“…The generic name Psammina was taken up by Hawksworth (1979) for a new lichenicolous species found growing on Schismatomma decolorans in Dorset (UK), and named P. stipitata. That species has subsequently been found on green coccoid algal crusts and a range of crustose and leprarioid lichens on both bark and rarely siliceous substrata in the UK, Denmark, The Netherlands, and Spain (Alstrup 1993;Earland-Bennett & Hawksworth 1999;Aptroot et al 2004). Two futher algicolous and lichenicolous species have also now been described as P. M. Earland-Bennett: 52 Rectory Grove, Leigh-on-Sea, Essex SS9 2HJ, UK.…”