alex_shure's Favorites

Holotype (CASIZ 182590), 33 mm long as shown here, on which Terry Gosliner based his 2010 description of this species (as Flabellina goddardi). I found it on a calm and bright overcast morning crawling in the open in a low intertidal pool at Tar Pits Reef. The 2nd image shows the egg mass, 14 mm in diameter, laid by this individual on 10 May 2008. The uncleaved zygotes averaged 65 microns in diameter, were packed one per capsule, and took 7 days at an average of 16 degrees C to develop into hatching planktotrophic veligers. The 3rd image shows, in right ventro-lateral view, one of the veligers just prior to hatching and with a shell 105 microns long.

Unlike most specimens of this species observed subtidally, individuals found intertidally vary in possession of white lines on the body and cephalic tentacles from completely absent (as in this specimen) to incomplete, to complete. With those white lines, subtidal specimens have occasionally been mistaken for Coryphella trilineata.

Not my observation: posted with the permission of Simon Hickman, who is not an iNat user, who found this on Lambert's Cove beach, West Tisbury. Presumably, it arrived at our latitude in a Gulf Stream eddy.

These crabs are quite common on the tidal flats in the North Eastham area, I've been seeing them for many years.

There's a paper, Phylogeny of the genus Pinnixa White, 1846 (Crustacea, Brachyura, Pinnotheridae) and allies inferred from mitochondrial and nuclear molecular markers, with generic reassignment of twenty-one species (By Emma PALACIOS THEIL & Darryl L. FELDER) - Link: https://sciencepress.mnhn.fr/en/periodiques/zoosystema/42/6 that contains a Morphological characteristic chart. The shape of the claws and male pleon align with Pinnixa cylindrica most closely.

There's another paper out there, THE OCCURRENCE OF PINNIXA CYLINDRICA (CRUSTACEA, PINNOTHERIDAE) IN THE TUBES OF THE LUGWORM, ARENICOLA CRISTATA (by John J. McDermott) - Link: https://www.jstor.org/stable/44112124 that describes Pinnixa cylindrica being found frequently alongside the Lugworm. There are many American Lugworm in the area as evidenced by their egg 'jellies'.

There are a few Cape-area Pinnixinae on iNat already, I believe these are also Pinnixa cylindrica:

• https://www.inaturalist.org/observations/113221758
• https://www.inaturalist.org/observations/92703005
• https://www.inaturalist.org/observations/6989329
• https://www.inaturalist.org/observations/131488437

I. Cruzii formerly - as a junior synonym.

These do not exist there in these numbers anymore, owing to - probably - diver numbers and probably bottom dwelling elasmobranchs. They exist elsewhere along the reef system.

Sandbar shark in Nantucket Harbor

Depth approx 7.5 ft
Water temp approx 74 F

View full observation video: https://youtu.be/0fPHQTvw8L8

Part of The Harbors Video Project -- https://www.theharborsvideoproject.org

I decided to dig a little ways down a burrow about 0.5 inches in diameter which felt like it had compacted/slightly cemented walls. Similar burrows in the area were very deep and had multiple entrances. All were in ~4 inches of water at dead low tide. I felt this fish fleeing headfirst down the hole and trapped it with my index finger against the burrow wall, maybe 7 inches down and pulled it out after digging down with my other hand to make some space to maneuver. I think the burrow continued deeper but I did not dig any more after pulling the fish out. I suspect that the burrow was made by the mud shrimp Upogebia affinis. I posted an exoskeleton from that species from the same location a little while ago and found another during this trip. I saw another goby maybe 1.5 cm long later in the day but didn’t catch it.

Observé lors d'un relevé au chalut de fond par MPO-Québec, collection IML no. 12357 / Observed during a bottom trawl survey by DFO-Quebec. MLI museum no. 12357. z = -103 m.
https://www.boldsystems.org/index.php/Public_RecordView?processid=PIMI075-23

Images show two specimens, each about 2 mm long, one found by Larry Harris, the other by JG, both on the ctenostome bryozoan Amathia dichotoma. The egg mass in the 3rd image measured 1.9 mm long and was spotted by Walter Lambert on a piece of drift eelgrass collected from the same site.

Silver Hake in Cape Cod Bay

Depth approx 60' (18 m)
Surface temp: 63 F (17 C)
Est. temp at depth: 49 F (9 C - based on other cameras in the area)

View full observation video: https://youtu.be/NYxxTVVz86s

Part of The Harbors Video Project -- https://www.theharborsvideoproject.org

'Hedgehog' amphipod sampled on the DFO-Quebec northern Gulf of St. Lawrence bottom trawl survey. MLI museum no. 12471 / Un amphipode « hérisson » échantillonné dans le cadre du relevé au chalut de fond du nord du golfe du Saint-Laurent du MPO-Québec. Collection IML no. 12471. z = -87 m.

Three individuals, 7 to 10 mm long, with their egg masses on Obelia, collected from New Harbor on 4 April.

The 3rd image shows an egg mass laid on 9 April, with two of its encapsulated zygotes (95 microns in diameter, in capsules 182 x 129 microns) shown in the last image. Easter eggs!

6 mm long crawling. Sac-shaped egg mass (3rd image) 0.9 mm wide. Zygote (4th image) 85 microns in diameter, shown with three mostly clear polar bodies in an egg capsule measuring 143 x 110 microns; a still swimming spermatozoon is visible at upper right in this image.

Exemple d'une méduse observée par MPO-C. Turcotte lors du relevé du plancton du PMZA-TL au bonnet Flamand, mis en collection IML no. 11974 / Example of a medusa observed by DFO-C. Turcotte from a AZMP-NL plankton survey at Flemish Cap, put in collection IML no. 11974. z=1000 m

Des exemples d'anémone de famille Hormathiidae au même trait de capture lors d'un relevé de chalut de bâton pour MPO-Québec. Gauche (haut et bas): Hormathia digitata, milieu: Hormathia nodosa (2). Aussi visible en haut-droit est Stomphia coccinea / Examples of the Hormathiidae anemone family in one set during a beam trawl crab survey by DFO-Quebec. Left (above and below) is Hormathia digitata, middle is Hormathia nodosa (2). Also visible in above-right is Stomphia coccinea. z = 103 m. Photo: Isabelle Lévesque (MPO-IML).