Yes, I think its a matter of phrasing. We did find several new records for Guam and the Marianas and also new species, too much to summarize in a short article.

Check out what we have been up to on our latest expedition!

(5) We hypothesise that gall crabs are able to offset negative effects of disturbances via increased reproductive output. Their high population turnover further suggests that they contribute to reef energy cycling by converting host-derived resources into forms accessible to higher life forms.

(4) By calculating turnover and mortality rates, we show that some reefs maintained reproductively active and resilient populations despite extensive bleaching, while compounded stressors at one site led to a population collapse.

(3) Fate-tracking revealed surprisingly high population turnover with steady colonisation and extinction events as well as settlement preferences for already inhabited hosts.

(2) We fate-tracked nearly 800 crabs for 2 years, capturing the 2023 Red Sea bleaching event. In addition, we performed belt transect surveys for comparison. These surveys showed that reef-specific effects drive gall crab abundance and prevalence over cross-shelf gradients.

Temporal Dynamics and Disturbance Responses in Coral‐Dwelling Decapods Provide a Novel Perspective on Their Ecological Role in Coral Reef Systems Our study investigates the temporal dynamics and disturbance responses of coral-dwelling gall crabs (Cryptochiridae), an overlooked yet ecologically significant group of obligate coral symbionts. By ....

Stoked to share the publication of another of my PhD chapters! This time we investigated the temporal dynamics of gall crab populations, representing the first data set of its kind for any coral-associated invert. (1) 🦀 🧪🪸
onlinelibrary.wiley.com/doi/10.1002/...

Unprecedented heat in the North Atlantic Ocean kickstarted Europe’s hellish 2023 summer. Now we know what caused it Parts of the Atlantic Ocean are again much warmer than normal, priming Europe for more extreme heat this summer.

Read the story behind our new study published yesterday in Nature, unfiltered straight from the scientists: 🌊
theconversation.com/unprecedente...

Saudi Arabia’s KAUST study finds gall crabs use fluorescence to blend into coral homes JEDDAH: Marine researchers from the King Abdullah University of Science and Technology have discovered that gall crabs use highly evolved fluorescence to help conceal themselves within coral hideouts....

Super excited that my PhD research made it on the national news of my chosen home for the past four years! @royalsocietypublishing.org 🦀🧪🪸🌍
arab.news/bvtne

(4) Our findings emphasize the need to better understand the ecological roles of cryptic symbionts on coral reefs, as these invertebrates are integral parts of multisymbiotic systems, yet their contributions to reef functioning remain largely unquantified. Huge thanks to everyone involved!

(3)The results were surprising: no consistent negative impact of gall crabs on photosynthetic efficiency.
In some cases, we even observed slight increases.
These findings suggest that crabs take a neutral role toward the algal symbionts of stony corals.

(2) Here we applied this technique—a method typically used to assess stress responses in coral algal symbionts—to coral-crab associations for the first time. This allowed us to look for potentially concealed local effects the crabs might have on the zooxanthellae in their hosts' tissue.

What would a PhD be without a side quest? 🦀🪸
Super excited our study is out in Frontiers in Marine Science!
We tested if gall crabs affect coral algal symbionts using Imaging PAM fluorometry.
Turns out—these tiny tenants don’t stress out the algae.
🔗 doi.org/10.3389/fmar... (1)

(6) Differences in fluorescence expression may be linked to variations in their microhabitats. Crabs living in enclosed galls don't fluoresce, while others inhabiting more open dwellings show vivid fluorescence. Fluorescence may play a role in camouflage on the fluorescent coral host background.

(5) By performing ancestral state reconstruction and combining the morphology results with a phylogenomic reconstruction, we show that fluorescence is phylogenetically widespread in the family. It evolved once in the genus Opecarcinus and was subsequently retained with varying expression levels.

(4) This analysis revealed four distinct fluorescent morphologies (Fluotypes). Each of these fluotypes has distinct characteristics, such as cheliped or abdominal fluorescence.

(3) We developed a fluorescent imaging technique for a multivariate trait analysis based on 27 morphological characters.

(2) We found gall crabs to display a vivid orange fluorescence that is visible without an excitation light source (A). Based on these observations, we hypothesised that it may be an adaptive trait for this family of decapods.

Proud PhD Moment 🦀 My third PhD chapter is finally released to the world, and the cherry on the cake: My photo made the cover of the current #ProcB issue @royalsocietypublishing.org 🪸 check it out here: doi.org/10.1098/rspb...

#CoralReefs #Biodiversity #Fluorescence #Symbiosis #Decapods

Dissertation writing break well spent although Red Sea February water temps are 🥶 #coralsky

Hey, never apologize for asking random questions about crabs! This is literally my career haha

the crabs perish. They can not survive long without a living host. They feed on coral mucus, so their food source disappears... I'm currently preparing the results of a long-term study on their response to bleaching for publication so stay tuned!

Hello Erick, *almost Dr :) Thanks for your interest in these critters. They can not leave their hosts; the females, especially, are almost forced to stay within their dwellings. When the coral bleaches they can persist, I found them to be actually quite resilient. However, if the host dies

Currently there are nearly 60 described gall crab species that settle on a really diverse set on host families. They are host specific though, to varying degrees. Some species settle on a single host species only, some others are a bit more flexible.

So far we have no strong evidence that their presence has any significant negative effects on their hosts but stay tuned for more research about this soon! 🦀
They do feed on coral mucus but since thats continously produced by the coral it doesn‘t seem to be very energy draining.

A shallow reef flat in August 2023 covered with branching corals. About half of them are live and yellow, while the rest are dead from natural mortality over the years.

A few bright white coral colonies in the reef flat that are undergoing bleaching in August 2024.

The same reef flat after the bleaching event. Photo taken December 2024. All colonies are grey and dead.

I started surveying the shallow reef flats in front of KAUST for my PhD in 2020. I was impressed that corals could live in such extreme conditions - the water hits 38ºC in the summer! However, heatwaves in '23 and '24 were too much even for these corals. Today's survey had nearly 100% mortality 😞 🌊🦑

Wow it looks like it's fluorescent and red fluorescence is not very common in decapods :O

Shoving the #crustmas cookies in my mouth like this porcelain crab

Had to dig for a bit but I found it! You can see it in front of it's claw floating through the water. @jopabinia.bsky.social in case you are interested too!

Pseudocryptochirus viridis indeed! Awesome find and cool photos :) @jopabinia.bsky.social