Guam's Rare Murex

by Jim Rodgers

Guam's first shell news letter would hardly be complete without mentioning one of the island's rarest shells. Murex laqueatus (Sowerby, 1841) (right). This lavender Murex was first identified in 1841 by Sowerby. Few if any specimens were found for the next 130 years. Then in the early 1970's collectors in Guam began gathering a strange unidentified Murex from Orote Point, near Apra Harbor. I believe, in 1972, Dr. Emily Vokes first recognized this shell as Murex laqueatus, from specimens furnished by Larry Saltzgaver. It has subsequently been found along most of Guam's coast line and from Rota and Saipan. Recent records from Kwajalein and Tahiti have shown that the species does have a wide Pacific range.

Perhaps one of the reasons this shell was not rediscovered sooner is its unusual habitat. The Orote cliffs seem to be the most reliable place to find a laqueatus. Several specimens have also been found on the outer slopes of a reef near Cocos Island. A very dead specimen was found near Double Reef. Many other areas have been searched while looking for this elusive Murex but with no luck! Even though habitat and environment seem to be identical to other areas inhabited by Murex laqueatus, none have been found. There are some areas on the North East side of the Island that would be likely spots, but most of them are not accessible because of the lack of places to launch boats. Rough water is also a problem there.

Very seldom if ever is a live Murex laqueatus found out in the open. They are nearly always deep inside natural caves or under large house size boulders. Most of these areas are inhabited by Turkey Fish and usually there is a school of Barracuda in the area. Sometimes the Murex can be seen but not reached because they are so far back under the overhang. Normally they are found between 50 and 100 feet but there have been and always will be exceptions. They seem to be seasonal. We have made as many as 50 dives in a three month period without finding a single shell. Normally in season we make saturation dives with several people. Usually we find at least one per day between all of us. After storms is a lousy time to look for Murex. During the storm they seem to go deep into the caves and crevices to avoid the turbulent water.

Never have I found a laqueatus that had growth marks on it. Some have been found where the fronds have been eroded away. They reach 40mm in size with the average Guam shell being about 1-3/4 inches. The majority of the Murex I have found needed only a little cleaning. When found alive they have a reddish-orange sponge covering. All the cleaning required is to get the animal out first and then drop the shell into a small container of straight bleach for about 5 minutes. Then take the shell out and rinse it with fresh water. Very seldom do you have to pick coral off them as is the case with most other Murexes.

One might think that Murex laqueatus is here to stay but there are some problems. Orote Point is only accessible by boat and there are many times when you cannot get to the area because of rough seas. Another problem is that Orote cliffs are in a location where the Navy periodically runs certain types of tests. When they are doing this you cannot dive nearby. Pollution has affected some of their habitat and is gradually affecting more in this area.

If Orote Point area were to be opened to any kind of construction work I am afraid that the area would really be adversely affected.