Since my parents live in southern California, I figured I'd make the most of my Spring Break by scheduling a visit to the Ichthyology-Herpetology
department at the LA County Museum of Natural History
(LACM). In this visit, I had the pleasure of meeting the Collections Manager (and all-around great guy), Rick Feeney. Very much like the Cal Academy
, the LACM houses many, many specimens that are organized in shelves -- reminiscent of most libraries. According to Rick, the collection contains over 5 million specimens.
|Each of these rows contains hundreds of jars of fish specimens.|
|You're not a true ichthyologist unless you come up with jokes like this.|
|Found this little gem lying around. Quality entertainment!|
In my ongoing quest to build ontogenetic series for Labrid fishes, I took advantage of the LACM's beautiful collection. Rick Feeney was quite generous with the number of specimens he was willing to loan to me -- he let me get away with 91 little fishies. Here are the spoils!
First up, we have Thalassoma bifasciatum
, also known as the bluehead wrasse. This Caribbean species is probably most well-known for being a protogynous hermaphrodite, although many other wrasses exhibit this condition as well. Thus, the largest individuals in a population tend to be terminal-phase males, who exhibit a distinct coloration. If they leave or die, large females will often change sex secondarily. Bluehead wrasses often eat zooplankton and small benthic crustaceans, but can also consume echinoderms and molluscs. This species is also a facultative (juvenile) cleaner of ectoparasites.
|A size series of Thalassoma bifasciatum (LACM 54098-040). |
Next, we have Halichoeres bivittatus
. I already have a few specimens of this species from the Cal Academy, which I highlighted in a previous post
. Another protogynous hermaphrodite from the Atlantic, this species also forms leks during breeding. Also unlike T. bifasciatum
, this species can undergo sex reversal. Whether any of this helped inspire the common name of "slippery dick wrasse" is a mystery to me. Anyway, this species is a gastropod-eater and occasional piscivore. As I mentioned before, this species is also a facultative (juvenile) cleaner!
|A size series of Halichoeres bivittatus (a.k.a H. bivittata, LACM 2479-000).|
These weird fellows below are specimens of Gomphosus varius, the bird wrasse. This Indo-Pacific species uses its elongate jaws to pick off small benthic invertebrates from coral or rocky crevices. Interestingly, this species does not clean, even though it possesses jaws that are conducive to a "picking" feeding mode. I guess it goes to show that there's a lot more to cleaning than having (presumably) adequate morphology -- behavioral ecology plays a huge role in determining the evolutionary trajectory of mutualistic behavior.
|Size series of Gomphosus varius (LACM 57407-001).|
|Some more specimens of Gomphosus varius (LACM 37434-005).|
Another familiar face: Halichoeres nicholsi
, the spinster wrasse. This facultative (juvenile) species is found in the eastern Pacific. Although it may be hard to really notice by looking at faded museum specimens, this species has very distinct coloration patterns for the juvenile and adult phases. Juveniles have a more blotchy/spotted coloration whereas adults are more uniform in color with a broad bar behind the head.
|A size series of Halichoeres nicholsi (LACM 32499-027).|
|Two juvenile specimens of Halichoeres nicholsi (LACM 43924-005).|
The tubelip wrasse, Labrichthys unilineatus
, is the most closely-related non-cleaning species to the obligate Labroides
and facultative Labropsis
cleaners in Labridae. Members of this monophyletic group, called the "labrichthynes", are known for having tube lips. Unlike its sister taxa, L. unilineatus
does not clean, and instead feeds on coral polyps.
|A few specimens of Labrichthys unilineatus (LACM 42489-026). |
Back to the world of Thalassoma
: next we have Thalassoma hardwicke
. This species, known as the sixbar wrasse for its characteristic stripes, can be found in the Indo-Pacific. It is not a cleaner, but rather a benthic invertivore.
|A size series of Thalassoma hardwicke (a.k.a. T. hardwickei, LACM 51859-049).|
|A few larger specimens of Thalassoma hardwicke (a.k.a. T. hardwickei, LACM 38210-004).|
The final species I will highlight tonight is Halichoeres dispilus
, the chameleon wrasse. Found in the eastern Pacific, this species feeds on benthic and pelagic invertebrates, but is not a cleaner. Large individuals have been observed to be piscivorous.
|A size series of Halichoeres dispilus (LACM 8104-000).|
|More specimens of Halichoeres dispilus (also from LACM 8104-000).|
|Two additional juveniles of Halichoeres dispilus (LACM 43822-001).|
I was fortunate enough to be able to borrow all of the specimens I have shown here, plus a few more. Much to my delight, Rick Feeney was fine with having me clear & stain these specimens, which is a pretty tall order. As such, I am very thankful to Rick and the rest of the staff at the Museum of Natural History. They run an amazing Ichthyology-Herpetology department, and made me feel very welcome working there for the day.
|A great group of folks -- the Ichthyology-Herpetology staff at the LA County Museum of Natural History.|