Visiting Scientist(s) Feature: Echinoderm Edition

(From left) Dr. David Lane, Ms. Ismiliana Wirawati, and Mr. Indra Bayu Vimono in the LKCNHM research lab.

This September, we have yet another bunch of research visitors at the museum to examine specimens from the recent SJADES deep-sea expedition!

This time, we are featuring three researchers who study echinoderms (i.e., marine animals such as sea stars, sea urchins, and sea cucumbers): Ms. Ismiliana Wirawati, Mr. Indra Bayu Vimono, and Dr. David Lane.

Dr. Lane is definitely no stranger to us, being one of our honorary research affiliates, and a frequent visitor. On the other hand, Ms. Wirawati and Mr. Vimono are researchers from the Indonesian Institute of Sciences (LIPI) in Jakarta, Indonesia.

Inner Beauty

Ms. Wirawati’s research focus is on the study of sea cucumbers, which she has studied for about a decade.

The sluggish sea creature’s duality was what drew her to studying them in greater detail. When examining sea cucumbers, taxonomists do not put much focus on their outer morphology (or appearance), focusing instead on microscopic internal structures composed of calcium carbonate, known as ossicles.

Ossicles from a deep-sea sea cucumber, examined under a microscope.

These ossicles come in varying shapes, with some resembling a table, and others resembling a cross, or a star, etc. According to Ms. Wirawati, sea cucumbers are really interesting as contrary to their dull outer appearance, the ossicles within their sluggish bodies are really pretty and fascinating.

“They may not look good on the outside, but it’s what’s inside that matters,” she said.

The shape and composition of these ossicles differ between different sea cucumbers. During this visit, Ms. Wirawati brought from Indonesia microscope slides containing ossicles extracted from deep-sea sea cucumbers in the orders Aspidochirotida, Molpadida, and Elasipodida, to observe under the microscope.

She also compared the ossicles with those in our collection. At this press time, she reckons that 80% of the deep-sea sea cucumbers are new records from Indonesia, but more research has to be done before she can determine if there are any species that are new to science.

Exhilarating Ocean Voyages

While Ms. Wirawati was working on sea cucumbers, Mr. Vimono and Dr. Lane were examining sea stars from the deep sea.

A deep-sea sea star, examined under a microscope.

Before the SJADES Expedition, the last deep-sea expeditions that sampled the Java Sea, and other deep seas around Indonesia, happened at the tail of the 19th century and in the early to middle of the last century, said Dr. Lane.

Thus, to familiarise themselves with the characteristics of deep-sea sea stars, the both of them were looking at old literature, for example Perey Sladen’s massive monograph, describing the specimens collected from the 1872–1876 voyage by the British Royal Navy survey ship, HMS Challenger.

That voyage can be considered to be magnificent effort considering the limited technology for sampling the deep-sea to pick up specimens or sediments, said Dr. Lane.

Even today, despite help from machinery and technology, it was still tough for the crew of the SJADES expedition. Other than battling seasickness, the crew also had to do a lot of tough work, such as sifting out trash from the trawl, recounted Mr. Vimono, who was part of the scientific team.

During their visit, the both of them examined sea star specimens, comparing them to those in the old and new literature. At press time, they reckon that most, if not all of them are new records for Indonesia, with a few potential new species.

We had a great time hosting Ms. Wirawati, Mr. Vimono, and Dr. Lane, and hope to see them again soon! 🙂