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Sandy bottoms are a ubiquitous environment found from sea bottoms to intertidal and freshwater zones. They are inhabited by many invertebrates and vertebrates which have developed morphological and physiological adaptations to sustain life under these particular conditions. Sandy habitats exhibit three potential constraints: abrasion, hypoxia and mechanical resistance. Here, three teleost species living in sandy environments were investigated: Ammodytes tobianus (Ammodytidae), Gorgasia preclara and Heteroconger hassi (Congridae). These teleost fishes were studied for their integument and muscular systems, which are potentially subject to sand abrasion and hypoxia, respectively. Based on histochemistry and transmission electron microscopy, we found the complex mucus system of G. preclara and H. hassi consists of two types of goblet cells and one type of sacciform cell. The secretions of both species are made of complex polysaccharides. In contrast, the scaly integument of A. tobianus has only a few goblet cells and no sacciform cells. We also highlighted, by immunohistochemistry, that the epidermal cell proliferation was much higher for this latter species, potentially resulting from the high rate of sand abrasion when A. tobianus buries itself quickly in the substrate. For all species, the major muscle fibre type was revealed by histoenzymology and corresponds to fast glycolytic fibres followed by intermediate fibres with slow fibres in the lowest proportion. Ammodytes tobianus possesses the highest fast fibre proportion (about 87% for A. tobianus and 75-78% for both garden eels). Our results provide new insights into the previously poorly studied teleost species, such as G. preclara, and allow us to highlight the complex skin histology of both garden eel species. Furthermore, the previously unknown muscle typing of these three species was determined.

Gorgasia punctata Meek & Hildebrand, 1923. Dotted Garden Eel or Peppered Garden Eel. To at least 50 cm (19.7 in) TL (Allen and Robertson 1994). Bah��a Santa Maria (24��46.1���N, 112��16���W), southern Baja California (Personal communication: Scripps Institution of Oceanography Fish Collection, La Jolla, California) to Panama (Smith in Fischer et al. 1995), including Gulf of California (Personal communication: Scripps Institution of Oceanography Fish Collection, La Jolla, California). Benthic; depth: less than 0.3 to 30 m (1���99 ft) (min.: Personal communication: Scripps Institution of Oceanography Fish Collection, La Jolla, California; max.: Robertson and Allen 2002)., Published as part of Love, Milton S., Bizzarro, Joseph J., Cornthwaite, Maria, Frable, Benjamin W. & Maslenikov, Katherine P., 2021, Checklist of marine and estuarine fishes from the Alaska-Yukon Border, Beaufort Sea, to Cabo San Lucas, Mexico, pp. 1-285 in Zootaxa 5053 (1) on page 38, DOI: 10.11646/zootaxa.5053.1.1, http://zenodo.org/record/5578008, {"references":["Allen, G. R. & Robertson, D. R. (1994) Fishes of the Tropical Eastern Pacific. University of Hawaii Press, Honolulu.","Fischer, W., Krupp, F., Schneider, W., Sommer, C., Carpenter, K. E. & Niem, V. H. (1995) Guia FAO para la identificacion para los fines de la pesca. Pacifico centro-oriental. Volume II, Vertebrados, Parte 1. Volume III, Vertebrados, Parte 2. FAO, Rome.","Robertson, D. R. & Allen, G. R. (2002) Shorefishes of the tropical eastern Pacific: an information system. CD-ROM. Smithsonian Tropical Research Institute, Balboa, Panama."]}

Garden eels occur worldwide in the tropics, but little is known about their biology and ecology. We studied Hawaiian garden eel ( Gorgasia hawaiiensis ) colonies near Kawaihae, Hawai‘i, to investigate multiple aspects of basic biology of this species. Colonies of G. hawaiiensis occurred at depths from 16 to 36 m in soft-bottom habitat adjacent to rocky reefs. Highest burrow densities (up to 40 eels m−2) were in shallower water, and large (~10 mm diameter) burrows were more abundant, less dense, and commonly found in pairs in deeper water. Eels emerged around sunrise and withdrew and covered burrow entrances around sunset. Age was estimated from annual rings in sectioned otoliths ( n = 17) and modeled to suggest fast growth to a maximum size of ~600 mm total length and a maximum age of 6 yr. Prey size and eel anatomy suggest that these fish feed by ingesting planktonic prey and processing them in the esophagus. The most common food items were small ( G. hawaiiensis is abundant, has a high population turnover rate, and may enrich sandy-bottom habitat within their beds by facilitating energy flow from the water column to the benthos.

[Figure][1] Garden eels in a current. Photo credit: Alexandra Khrizman. Plankton sure is a popular dining choice amongst aquatic species. Some birds even feast on the tiniest ocean creatures as they plunge through the waves. Yet, garden eels ( Gorgasia sillneri ) seem to go against the

The behavior and reproductive ecology of typically nocturnal marine eels is poorly known but garden eels (Congridae, Heterocongrinae) are familiar tropical marine eels. They live in colonies and protrude their bodies from burrows during the daytime to feed on zooplankton. Apparent daytime courtship/spawning-like behavior has been observed within the colonies but actual spawning and fertilized egg production has not been confirmed. This study describes observations of splendid garden eels (Gorgasia preclara) and spotted garden eels (Heteroconger hassi) spawning in low light at night and producing fertilized eggs in a large multispecies public-display tank in the Sumida Aquarium. Video recordings of 5 of 17 detected spawning or egg or sperm release events documented the spawning behavior of G. preclara, and positively buoyant fertilized eggs of both species were collected. Their spawning behavior while protruding from widely spaced burrows confirms that garden eels likely spawn within their colonies with th...

Gorgasia japonica Abe, Miki & Asai, 1977 R���№�� Gorgasia japonica Abe, Miki & Asai, 1977: 1, pl. 1, fig. 2 (type locality: near Hachijo-Kojima, 33 ��07'N, 139 �� 42 'E, Japan). Shao, 1990: 11. Remarks. This is a rare species and has only been recorded from Lan-yu Island off southeastern Taiwan., Published as part of Ho, Hsuan-Ching, Smith, David G., Mccosker, John E., Hibino, Yusuke, Loh, Kar-Hoe, Tighe, Kenneth A. & Shao, Kwang-Tsao, 2015, Annotated checklist of eels (orders Anguilliformes and Saccopharyngiformes) from Taiwan, pp. 140-189 in Zootaxa 4060 (1) on page 147, DOI: 10.11646/zootaxa.4060.1.16, http://zenodo.org/record/243651, {"references":["Abe, T., Miki, M. & Asai, M. (1977) Description of a new garden eel from Japan. Uo (Japanese Society of Ichthyologists), 28, 1 - 8.","Shao, K. - T. (1990) Garden eels from Taiwan, with description of a new species. Uo (Japanese Society of Ichthyologists), 40, 1 - 16."]}

Background Moray eels (Muraenidae, Pisces) are among the largest benthic predators of littoral habitats, particularly in warm seas and coral reefs. They seek food either by olfaction or visually, moving across the pebbles and rocks. Their skin forms a strong, protective layer. This study examines the comparative morphology and cytology of the skin of moray eels adapted to such lifestyles. Methods The studied eels were collected in the Gulf of Aqaba, Red Sea and sacrificed by an overdose of MS222. Skin selections from different body sites were dissected and fixed for light and electron microscopy. Results The skin of moray eels (Siderea grisea, Lycodontis nudivomer, Gymnothorax undulata, G. hepaticus, Rhinomuraena amboensis) and the heterocongrid garden eel (Gorgasia sillneri) reveal considerable adaptation of the integument to their different lifestyles, on and within the various bottom substrata. All the eels studied featured skin comprising, a multilayered, stratified epidermis and a compact, collagenous dermis, with thickness of up to 2 mm, much thicker than that observed in their free-swimming relatives. The thickness and cytology of the two skin layers differ in the various species on different body sites within the same species and also changes with age. Pronounced differences were observed in the number and type of mucus-producing cells in the epidermis. In S. grisea, the entire body is covered by a multiple layer of goblet cells, whereas in G. sillneri, sacciform cells predominate, particularly on the caudal part of the body where they form an uninterrupted layer, replacing the supporting cells that surround them. These cells are also dominant in R. amboensis. The two latter species are sand-dwelling and the copious production of slime from these cells enables the adhesion of sand granules to their burrow walls. In Gorgasia, a special morphological adaptation was also observed in its pointed tail-end where the very strong dermal collagen forms a rigid device for digging tail-first into the sand. Conclusion The differing thicknesses and cytological developments in the skin of marine eels protect these crawling and digging creatures against abrasive interaction with their sea bottom habitat. © 1996 Wiley-Liss, Inc.

63. Gorgasia taiwanensis Shao, 1990:4, figs. 2–6 Holotype: ASIZP 56584 (538 TL), Wan –li–tung, Hengchun, southern part of Taiwan, 21°58'N, 120°43'E, 22 m, 15 Apr. 1989, coll. K. – T. Shao. Paratype: ASIZP 56585 (6, 454–741 TL), Wan–li–tung, 22 m, 15 Mar. 1989; ASIZP 56586 (9, 534–721 TL), Wan– li–tung, 14 m, 18 Mar. 1986; BPBM 33506 (1, 496 TL), SMF 22498 (1, 638 TL), and ZUMT 56359 (1, 549 TL), sand area at a depth of 20 m, 2 Feb. 1987. Remark. One paratype, ZUMT 56359, is probably still in Abe’s collection (Sakamoto, pers. Comm., Oct. 2007)., Published as part of Ho, Hsuan-Ching & Shao, Kwang-Tsao, 2011, 2957, pp. 1-74 in Zootaxa 2957 on page 23, {"references":["Shao, K. - T. (1990) Garden eels from Taiwan, with description of a new species. Uo (Japanese Society of Ichthyology), 40, 1 - 16."]}

Responses of four species of eels to the venoms of two species of sea snakes, a dietary generalist (Aipysurus laevis) and an eel specialist (Laticauda colubrina), were compared. All eels tested were more resistant to the specialist venom than to that of the generalist. Two muraenid eels (Gymnothorax hepaticus and G. undulatus), both sympatric with both sea snakes and probably their prey, were found to be remarkably resistant to venom. By contrast, two species of garden eels (Heteroconger hassi and Gorgasia maculata), sympatric with the snakes but unlikely to be preyed upon by them, were sensitive, as was an allopatric eel (Anguilla rostrata). Because Anguilla, an eel with good gaseous exchange through the skin, is sensitive to venom, it is unlikely that cutaneous respiration is the sole mechanism of resistance.

Leptocephali of Taenioconger sp. are positively identified and described. Growth, metamorphosis and the distribution of the leptocephali of Taenioconger sp. in the eastern Pacific are studied. A metamorphic leptocephalus of Gorgasia sp. is identified for the first time and described. The occurrence of this leptocephalus indicates the presence of a second species of Gorgasia in the eastern Pacific. The differences between the leptocephali of Taenioconger and Gorgasia, and the heterocongrine and congrid leptocephali are pointed out. Relationships of heterocongrines are discussed. Fricke's hypothesis (1970) that garden eels have no pelagic larval life is refuted.