Dendronotus nanus

Image courtesy of Herb Gruenhagen
La Jolla Shores,San Diego, Calif

Dendronotus nanus Marcus & Marcus, 1967

The coloration of this Dendronotid is similar to Dendronotus iris but the dorsolateral appendages appear stubby and there may be numerous white spots on the body. In all color forms there is an opaque white line around the foot.

The maximum size is unknown. The original description was from a 13 mm specimen (hence 'nanus' indicating its small size) but we suspect specimens can be much larger. It ranges north from its type locality of Puerto Penasco, Sonora, Mexico. Photographs of this "stubby" form are found from at least Puget Sound to Baja California.

Some internal differences in the reproductive systems have been noted between Dendronotus iris and D. nanus, so until genetic analysis is performed on both forms, we consider the two species to be separate.

Dave Behrens
Sammamish, WA 98074
Oct., 2022
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Herb at La Jolla Shores

This week I want to introduce you to Mr. La Jolla Shores-the goto guy with any questions regarding La Jolla Shores diving-Herb Gruenhagen

Herb made his first appearance on the site back in 1999 as a finder for Garry McCarthy's presentation on Cerbrilla sp. Herb was also the genesis for a later BOW featuring unusual behavior by Navanax inermis

Herb has been diving for some 53 years since 1968, a record few of us are going to equal in this life time! Compared to Herb I am a late bloomer having certified back in 1977 and jumping into U/W photography around 1982.

Herb has been San Diego Underwater Photography (SDUPS) past president for five years and a PADI Divemaster since 2005. Herb in his spare time teaches REEF citizen Scientist classes at Ocean Enterprise Dive Shop here in San Diego for both inverts and local inshore fishes.( Herb has donated images for the Walter Monk Foundation La Jolla Shores image exhibition in addition for making at least a dozen short image presentations for past SDUPS Film Festivals. Herb was master of ceremonies twice for the yearly SDUPS Film Festivals.

Hey, want to dive with Herb? Herb dives the shores three times a week as part of his citizen scientist participation! Drop Herb a note if interested!

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Mike Miller
San Diego, Calif 92113
Oct., 2022
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