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This view shows the same individual from the dorsal aspect.
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In this ventral view of the anterior half of the body, the gnathopods present at the anterior end of pereonite 1 and at the posterior end of pereonite 2 are visible. It has no gills on either of these pereonites.
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In this ventral view of the posterior half of the body (head is to right), the flat leaflike gills can be seen on midsections of pereonites 3 and 4 (part of the second gnathopods can be seen at the right on pereonite 2). Ahead of each gill is a small bump which is the vestigial pereopod for that pereonite. Pereonites 5-7 on the left have well-developed pereopods which act as claws to attach the animal to the eelgrass.
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This view shows pereonites 3 and 4 closer up (the end of pereonite 2 with ghathopod 2 is visible to the right). On each of pereonites 3 and 4 a small, 1-article vestigial pereopod can be seen projecting from near the front of the article and a leaflike gill projects from farther back. Note the large dorsal, forward-directed spine on both pereonite 3 and 4.
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In this lateral view of the head and antennae 2, the long setae on antennae 2 can be seen. The next to last article of antenna 2 is about 6x as long as wide and has setae at least 2x as long as the article is wide. Notice also the large, single dorsal spine on the head and the small first gnathopods at the anterior end of pereonite 1. The large first antennae are extending upward out of the picture.
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This dorsal view of the head shows more clearly the first and second antennae.
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Tritella pilimana found on eelgrass on March Point, Padilla Bay June 2007. Total length not including antennae = 2.4 cm. (Photo by: Dave Cowles July 2007)
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In gammarid amphipods the last three abdominal legs are uropods. This view shows a dorsal view of uropods 1 (lowest) to 3 on the left side of the animal. Above the base of uropod 3 the telson can be seen, then uropod 3 on the right side of the animal is visible at the very top. Uropods 1 and 2 have two similar rami composed of flattened blades with setae along the edges. Uropod 3 has a paddlelike inner ramus (seen on edge on the left, close uropod and from the flat side on the right, far uropod). The outer ramus of uropod 3 is less flattened and has two apical teeth, as seen below.
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This closeup view of left uropod 3 seen from the dorsal aspect of the left side shows the two apical teeth on the lateral ramus, and also shows the paddlelike inner (medial) ramus.
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This ventral view of the right uropod #2 shows the spine which extends from the base (peduncle) out between the two rami.
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In this dorsal view of the tail all three uropods plus the telson can be seen. The telson is short and evenly rounded.
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Neither antenna has an accessory flagellum, which would be a short branch based beside the main flagellum (the flagellum is the flexible, whiplike distal portion of the antennae, with many short articles which allow it to bend easily). The articles at the base of the flagellum of the second antenna are not fused together. In this photo the first antennae are to the left and the second antennae are to their right, curled around the first two pereopod legs (called gnathopods)
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This is a view of the left gnathopods (#1 is to the left, #2 next to it to the right). Gnathopods have 7 segments, the last two of which form a (usually subchelate) claw. In this view the 7th segment (the movable tip of the claw) is folding away from the view plane. Segment 5 of gnathopod 1 is longer than segment 6.
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In this view it can be seen that the last two pereopods (walking legs), # 6 and 7, are of similar length, but #7 is slightly longer. A live video of this individual can be viewed here.
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This female was carrying at least 11 larvae in her oostegite brood bpouch, Two of the larvae are shown above. They are about 3 mm long plus the antennae. The young appeared to be sticking their heads (cephalon) out and peering out from the pouch as the mother moved around, so I am guessing they are nearing the time when they can safely leave the mother.
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Peramphithoe humeralis, a large adult female about 3 cm long + antennae. Found in late October under a stone at extreme low tide (-3) at Sares Head. This female is carrying babies between her oostegites. Two babies can be seen peeking out from below her body behind leg 5 (angled forward) and in front of leg 6 (angled backward). (Photo by: Dave Cowles, October 2007) Identified with the help of Craig Staude
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Mayerella banksia (Laubitz, 1970) Common name: Skeleton Shrimp Mayerella banksia collected at Rosario Bay among drift algae. Photo by: Christina Smith, June2002
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This closeup shows pereonites 5-7 with their appendages, pereopods 5-7. Pereopods 5-7 arise from the posterior end of their segment (pereonite) and are used for gripping the substrate such as this eelgrass blade. The left pereopod 7 is missing.
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The propodus of gnathopod 2 is less than 2/3 as wide as it is long. Note also the gill on the segment behind.
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This ventral view shows there is no spine between the large gnathopods 2 and shows the location of the gills.
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This view of the head (animal is looking to the left) shows the very large second antennae to the left, then the head with sessile eyes and prominent, forward-directed head spine. Below the head can be seen the first gnathopods which are on the anterior end of the first thoracic segment (pereonite), which extends out of view to the right.