The collection of a lifetime

Curator Dr Nancy Mercado Salas is standing at a laboratory workbench in the LIB’s crustacean collection of the Museum der Natur in Hamburg, unscrewing the yellow cap of a plastic tube with crustaceans and a handwritten note inside. A sharp, fishy smell of alcohol rises briefly when she removes the latter with tweezers to spread it out on a plastic sheet to take a picture. “This says ‘Geograpsus lividus. Mulegé Lighthouse, Baja California’. This coastal crab species was collected at a lighthouse near the small Mexican town of Mulegé in Baja California. It is part of the collection of Christoph Schubart, one of the world’s most important crustacean researchers of recent decades. “This may even be his own handwriting,” says Nancy Mercado Salas, who also manages the LIB’s crustacean research group.
After Christoph Schubart’s death on a study trip to Jamaica in 2023, his family and the University of Regensburg bequeathed his scientific legacy to the LIB. 27 years had given him plenty of time to build a collection of about 5,000 crustacean specimens and 35,000 DNA and tissue samples from 85 countries around the world. Mercado Salas and her technical assistant Kathrin Philipps-Bussau helped Schubart’s colleagues at the University of Regensburg, where he taught before his death, to pack the physical specimens into crates for the ride to Hamburg, where they are about to become an integral part of the local crustacean collection.

Valuable expansion

Volunteer research assistant Dr Detlef Thofern is pouring 70% alcohol from a silver ethanol tank into a small screw-top jar to hand to Mercado Salas. “I transfer the crustaceans and their original labels to this jar with fresh alcohol, apply an inventory number, and shelve them over there to complete the transfer. Detlef then merely needs to enter the metadata and the photo taken of the label into our digital database," explains Mercado Salas. She and Thofern walk along the rows upon rows of shelves with screw-top jars of all sizes, containing crustaceans preserved in ethanol. Thofern says: “We have integrated about 4,000 specimens into our collection since May 2024. Our colleague Julia Eisermann has been helping us. Even now, there are about 1,000 to 2,000 samples left to rehouse.”
A range of about 850,000 specimens of some 7,200 species makes the LIB’s Crustacea collection the largest crustacean collection in Germany and one of the most important collections in the world. “We are adding about 1,000 new species to our collection right now. We haven’t had the opportunity to expand by such a leap in the last century. The scientific value of this work is enormous,” says Mercado Salas. She also considers this collection to be a space filled with stories. “All these animals serve as windows that afford us some glimpses of distant places and eras of the far-distant past. They also tell us about the people who collected them.”

The rows of his Excel frame the life of the researcher he has been tracking around the world for almost two years now. “I’m reconstructing Christoph Schubart’s academic life to digitise his collection. He took many trips to Jamaica and his native Spain, collecting extensively along the Mediterranean coast there. He was often accompanied by colleagues, students, and frequently by his children.” Some days make Thofern feel like he’s working as a P.I. “We are trying to compile maps to reflect the precise locations in which the specimens were found. When rain or intense heat in tropical regions have rendered labels hard to read, I need to work hard to find things such as missing coordinates.”

Travelling with friends

Schubart visited 85 countries on his collecting expeditions – with Afghanistan, Cabo Verde, Cuba, Syria, and China numbering amongst them. His longtime friend and colleague, Dr Jose A. Cuesta, accompanied him on some of these trips. A marine biologist at the Andalusian Institute of Marine Sciences (ICMAN-CSIC), Dr Cuesta wrote his dissertation on Grapsids, a family of decapod crustaceans, in the early 1990s just like Schubart.
Following an exchange by email in 1996, Schubart invited him along on a trip through Panama and Costa Rica. For ten days, the two scientists travelled together, taking samples from rivers, beaches, and mangrove forests. “It was an intense experience that, I am happy to say, marked the beginning of our friendship of 27 years,” says Cuesta.
“Christoph had great discipline. He never lost sight of his goal.” In the evenings, whatever hotel bathroom they had at the time became their lab. “We would label samples, fill the sink with ice to cool down the collected DNA samples and our specimens kept in ethanol,” Cuesta tells us.

Jose A. Cuesta confirms that Schubart would display a child-like glee when he found what he was looking for.
“We once took a boat across the rivers of Tortuguero National Park with our captain Tino back then. Christoph suspected that he would be able to find a Sesarma crassipes specimen there that he needed for his dissertation, later published in the scientific journal “Nature”. We were about ready to head back when a crab came crawling out of a tree trunk and I said, ‘How about taking that one?’ He threw himself at the animal with both hands outstretched like a goalkeeper saving the day. Once he saw what he was holding, he shouted with joy,” Cuesta recounts.
Cuesta deeply misses their personal interactions as well as their professional collaboration. “We would talk a lot once work was done, also about world events. We had shared values. We saw no borders. Animals aren’t Spanish or German after all. They live on a continent and are constantly on the move. Nature knows no nationalities,” Cuesta says. Schubart was fluent in many languages and believed in the inherent goodness of humankind. “That might be what had him go through life so openly and fearlessly,” Cuesta muses. He always felt safe with Schubart by his side, whether they were travelling together through the dangerous Darién Gap jungle or hitchhiking to Baja California in Mexico at a later time. Just nine days before his death, the two were talking about upcoming projects and his retirement. Cuesta continued, “I’ll be retiring in six years. Christoph wouldn’t even think of that. He had so many projects he still wanted to complete. I sincerely hope that the collection will be used and that his work will be continued by others.”

A living heritage

Jonas Astrin and the biobank team have teamed up with Nancy Mercado Salas and Detlef Thofern to process queries from scientists around the world. “The collection is already being used in projects,” says Mercado Salas. “Once we have finished rehousing all of these crustaceans at LIB Hamburg, the metadata of the physical specimens will be linked to the data from the DNA samples in the biobank and made available online in the LIB catalogue.” Integration of the collection is expected to be completed by 2028.
When working in the office, Detlef Thofern periodically checks on the crustacean collection to monitor ethanol levels in the wet specimens and tend to animals not yet sorted into their final places. Thofern has been involved in this process from the outset. He says: “I want my ‘children’ here in the collection properly cared for. They are to get a good home where they will always go out into the world in good condition.” He and Mercado Salas consider their work a tribute to every individual animal and to the person who travelled the world to collect them at the same time. The Schubart Collection is to turn into a living legacy that future generations of researchers can also utilise. Thofern says: “We are doing work for the future here.”