Hello again Foldscope community! I wanted to share with you all some awesome pictures I took of an amphipod, which a couple of us graduate students from CSU Monterey Bay found out at the intertidal zone at Carmel Point in Carmel, California. The images below are (1) a shot of the intertidal zone at Carmel Point during low tide and (2) a picture of us CSUMB graduate students looking for specimens to look at under our Foldscopes at Carmel Point!


Cherisa Friedlander, Larissa Lemon (two other CSUMB graduate students) and I sat in our classroom looking through a jar of water and algae that we collected while out at the intertidal zone of Carmel Point. It was our lucky day when we realized that we stumbled upon an amphipod in our water sample! The order Amphipoda is within the phylum Arthropoda and the subphylum Crustacea. Amphipods resemble shrimp and consist of both marine and freshwater forms (Lowry and Springthorpe 2001). I am not adversed in my amphipod species identification, but could this specimen potentially be the herbivorous marine species Ampithoe longimana (Duffy and Hay 1991)? Thoughts anyone?
Image of Amphipod exoskeleton and intestine.
Image of Amphipod mouthparts and antennae.
Image of close-up amphipod mouthparts.
In my opinion, it is difficult to identify different species of amphipods because they look very similar. For this reason, amphipods are often identified either by their mouthparts, their antennae, or by dissection (Lowry and Springthorpe 2001). By looking at the mouthpart pictures I’ve taken of this specimen, do any amphipod experts out there have an idea of what species this may be? We are fortunate that we have Foldscopes to help us identify organisms such as this! Being able to use Foldscopes in the field to identify smaller specimens is one big perk of this portable tool.
I am curious as to what this amphipod may have been eating and using as habitat. In the marine environment, amphipods have been documented as herbivores, scavengers, detritivores, and micropredators (Lowry and Springthorpe 2001). Amphipods have also been documented to eat seaweeds (Duffy and Hay 1991; Duffy 1990). In addition, amphipods help to benefit their environment by grazing on filamentous algae, and reducing the growth of competing algae species (Duffy 1990). Duffy and Hay (1991) point out that since amphipods are so small, to reduce the risk of predation, they may choose to eat plants that also provide them with refuge from predators.
We found our amphipod living on a mass of cladophora, a type of green algae we often saw out in the intertidal zone. The cladophora didn’t appear to be the most protective habitat for the amphipod, but maybe it could potentially be a good food source high in nutrient value. I decided to take a sample of the cladophora and put it under my Foldscope to see if I could find anything interesting. Below is the image of the cladophora under my Foldscope.

Any thoughts from anyone as to why we found an amphipod on a sample of cladophora, rather than a more protective plant species?
My Foldscope adventures today taught me several important lessons:

1. We can use Foldscopes to help us identify tiny organisms, which may be hard to identify in the field.
2. Being able to attach your Foldscope to your phone camera allows you to take high quality images of specimens, which can then be shared with the scientific community in order to answer scientific questions.
3. Placing larger objects (such as an amphipod) on a slide and under a Foldscope is a bit challenging. Next time, I may try dissecting the organism first, and then creating multiple slides in order to get better and more informative images.

A big thank you to Cherisa and Larissa for working with me to get these cool photos. Thanks for reading! Keep on exploring!
Just keep swimming,
Erika Senyk
References
Duffy JE. 1990. Amphipods on seaweeds: partners or pests? Oecologia 83: 267-276.
Duffy JE and ME Hay. 1991. Food and shelter as determinants of food choice by an herbivorous marine amphipod. Ecology 72: 1286-1298.
Lowry JK and RT Springthorpe. 2001. Amphipoda: families. Available from http://www.crustacea.net/crustace/amphipoda/index.htm