Lichens in New Zealand - Observation of the Week 2018-11-24

This group of Placopsis lichens, seen in New Zealand by linda_johnson, is our Observation of the Week!

Since she joined the Royal Forest & Bird Protection Society of New Zealand, Inc. (Forest & Bird  for short) a dozen years ago, Linda Johnson says “My interest and knowledge [in nature] has grown a lot.” She’s a coordinator for the Kiwi Conservation Club, a junior section of Forest & Bird, and “preparing nature-based activities for the KCC children has been a significant contributor to my increased knowledge about nature.” She also take part in pest control initiatives and restoration work.

Linda recently spent five days and four nights hiking The Old Ghost Road (OGR), an abandoned mining road in New Zealand’s Kahurangi National Park, and recounts

Whenever I'm out hiking I'm taking notice of what is around me and regularly stopping to get a better look around without falling over. The first day of the OGR was in beautiful beech forest and there was an abundance of bird life, especially NZ robins. On the second day we got up above the tree line and I was seeing plants I don't usually have an opportunity to see. The day was sunny and a section of the track had a rocky bank with grass and other low growing vegetation on it. There were some big boulders not covered by vegetation. The colours and shapes of the lichen on the rocks were eye catching so I stopped to take a photo.

The lichens she photographed are in the genus Placopsis, which are often referred to as “bullseye lichen” due to the their appearance. A crustose lichen, they grow tightly to their substrate (in this case a rock) and their more conspicuous structures are often grouped toward the center, with the thallus extending outward. Lichens can reproduce both sexually and asexually, and it looks like sexual reproductive structures called apothecia are the dark red dots fringed by lighter tissue. I’m not sure what the striking structures in the middle are - if you know, write in the comments!

Linda (above, on the OGR), mainly uses iNat for ID help and to make sure there are records for particular places. “For instance, I uploaded photos from my visits to the Chatham Islands (800km east of New Zealand), and subsequently was told I was the first person to submit data from there,” she says. “I actually started taking more photos on the OGR with iNaturalist in mind after taking the lichen photo.”

- by Tony Iwane

- Lichens have long been thought to be a symbiosis between a fungus and algae or cyanobactera, but recently a third partner has been found.

- Do lichens age? A Harvard mycologist has been studying lichens in a cemetery in an attempt to answer that question.

Posted on August 28, 2020 01:41 PM by hannahsun99