November 14, Fish Friday 1. Scombroidei 2. Grab bag of small marine fishes 3. We will read the Karieva et al. paper for next Wednesday (not Monday). Life tables next week! Test #2 - Not so good as test #1. Grand Average = 37.9 (76%) Undergraduate Average = 34.4 (68.8% - ouch!) Graduate Average = 44.5 (89%) If necessary, there might be a scale at the end. I prefer to let the extra-credit bring the grades up. Trachinoidei - sand divers, sand lances, weeverfishes, stargazers Callionymoidei - dragonets Gobiosocoidei - clingfishes Blenniodei - All sorts of blennies, sand stargazers, and kelpfishes Were here. Trachinoidei - sand divers, sand lances, weeverfishes, stargazers Callionymoidei - dragonets Gobiosocoidei - clingfishes Blenniodei - All sorts of blennies, sand stargazers, and kelpfishes Trachinoidei weaverfish sand divers Stargazers -live life under the sand - pectoral fins as shovels -eyes, nostrils, and mouth placed above sand -eyes capable of protruding a short distance -some have internal nares (inhale water through nostrils) - some can produce electric current through specialized pouch in the eye --> for defense Stargazers -spawn eggs on the bottom, but they float to the surface -have venomous spines on pectoral f in and behind opercle - can supposedly be fatal under the right circumstances stargazer video The developmental stages of the northern stargazer larvae. Note the migration of the eyes. in Development of Fishes of the Mid-Atlantic Bight - U.S. Fish and Wildlife Service Stargazers -eyes on the sides of head of juveniles, but migrate to top in adults. Weeverfish -Very similar to stargazers -eyes dorsal, mouth verticle, fringes to prevent sand getting in mouth - Also live in sand - Also have venomous spines --> associated with gill cover spine and first dorsal spine --> people get stung when they step on them filleting weever fish Sandeels and Sandlances -small, slender marine fish - protruding lower jaw - forked caudal fin -long dorsal fin -lacks a swim bladder -burrows in sand -common in temperate to cool seas -pelvic fins reduced or absent sanddivers - 6 species - indo-West Pacific -dorsal fin with anterior ray extended in males and used for display -hover in groups in shallow water, but diver into sand when alarmed Blennies The term blenny can refer to any of the following groups: triplefin blennies, pikeblennies, tubeblennies, and combtooth blennies. The family Bleniidae refers to the combtooth blennies spp. - Blennies have male (or rarely, bi-) parental care and have sticky, demersal eggs. blenny video Combtooth Blennies -Single continuous dorsal fin -- often w/flexible spines in front and soft rays in back. -Pelvic fins right under throat and proceed the pectoral fins. -Long anal fin. -Fringes (cirri) on heads of most. -Combtooth refers numerous, loosely packed teeth over jaw. -Pelagic larvae -Diets quite diverse (algae, aquatic invertebrates, plankton, skin/scales of others). -Small, benthic fish Butterfly blenny - max size 8 in. Tompot blenny - max size 12 in. Tasmanian Blenny Barnacle Blenny Bicolor blenny -lives in rocks/holes in coral reefs - comes out to eat algae -supposedly, both males and females have two-toned color Clingfishes -120 spp. - family Gobiesocidae - designed for clinging to rocks in the intertidal -small, tadpole-like fishes with pelvic fin united into a large sucking disc -lack scales, spines, and a swimbladder - tend to be small -lays eggs in a clump under a boulder -guarded by a parent -larvae and young fish planktonic -soon settle on seabed dragonet breeding Dragonets - highly colored fish w/ showy fins - often sexually dimorphic - eggs and young are pelagic - elaborate courtship Review Questions. 1. Describe the position of the pectoral and pelvic fins for the following groups: stargazers, weeverfish, sanddivers, blennies, clingfish, dragonets. Which of these fish have venom associated with spines? Where are these venomous spines located. 2. Describe the mating systems of stargzers, blennies, clingfishes, and dragonets. 3. Describe the adaptations of stargazers and weeverfish that allow them to live submerged in the sand. 4. Where do clingfish live and how does the morphology of their pelvic fins reflect this? 5. Who are the sabre-toothed blennies and what do they eat? Describe their strategy for eating.