DUDRESNAYA PATULA SP. NOV., AN UNUSUAL DEEP-WATER RED ALGA FROM FLORIDA1

Dudresnaya patula sp. nov. is described from 30–60 m depth on the east coast of Florida. The plant grows to a height of at least 10 cm, has flattened axes and main branches to 2 cm wide and 3 mm thick, and has unusually long female reproductive branches. The new species is compared to other Dudresnaya species in habitat, vegetative structure, and reproductive morphology.     

Movements and Site Fidelity of two Juvenile Fish Species Using Surf Zone Nursery Habitats Along The Southeastern North Carolina Coast

We examined the extent of movements of juvenile Florida pompano, Trachinotus carolinus, and gulf kingfish, Menticirrhus littoralis, along an open ocean beach. Fishes were collected by seine at three sites along Masonboro Island and Carolina Beach, NC between 7 June and 7 July 1995. All specimens 40 mm standard length (SL) were tagged with coded wire tags and released at the capture sites. Between 7 July and 9 August and on 15–16 September Masonboro Island and northern Carolina Beach were surveyed for tagged fish. A controlled tag mortality/retention study was conducted for both species. Overall, 1569 Florida pompano (40–135 mm SL) were tagged. Sixty-one (3.9%) of these were recaptured, and only eight moved away from the original tagging sites. The largest movements by two Florida pompano were 2.1 and 10.5 km. Many fish remained at their original tagging sites for 21–27 days. Of 488 gulf kingfish (36–158 mm SL) tagged, 16 (3.3%) were recaptured. Gulf kingfish also exhibited little movement away from tagging sites during the study, with individuals remaining at original tagging sites up to 21 days. Stock size estimates for Florida pompano ranged from 3354 to 4670 among the tagging sites, with densities ranging from 1.9 to 2.6 fish m^–2. The remarkable site fidelity exhibited by these two species suggests that resources were not limiting or that predation pressure was not high enough to cause large scale movements during the study. This implies that local disturbances could impact behavior or survival of juvenile fishes in the surf zone.     

Granilin and ivasperin from Ambrosia polystachya. 13C-NMR spectra of hydroxylated isoalantones

The eudesmanolides granilin and ivasperin were isolated from Ambrosia polystachya DC. ¹³C-NMR spectra are reported for these and other naturally-occurring ring A-hydroxylated isoalantolactones.     

Rhizophora mangle L. Seedling Development into the Sapling Stage across Resource and Stress Gradients in Subtropical Florida1

Nutrient, light, salinity, soil redox potentials, and other soil characteristics were determined across a range of mangrove forest heights across the South Florida peninsula encompassing large-stature trees (> 10 m) on the west coast and dwarf forms (< 1 m) in the southeast Everglades. Relationships were established between abiotic factors and Rhizophora mangle seedling growth rates in four height (cm) classes, 25-40, > 40-55, > 55–70, and > 70–85. Light in open canopy gaps was an important determinant of seedling growth. Growth rates in gaps (0.32 ± 0.04 to 1.89 ± 0.18 mm/d) were two- to five-fold greater than adjacent closed canopy forests (0.14 ± 0.01 to 0.40 ± 0.07 mm/d). Among open canopy sites, labile soil phosphorus and soil redox potentials were significantly correlated to growth (P < 0.05; r= 0.98 and 0.89, respectively). Interstitial salinity ranged from 0 to 27 ppt across sites, well below hypersaline conditions. Thus, under low salinity stress and high light availabiliry, soil fertility is proposed to be the dominant factor controlling R. mangle seedling development to a sapling stage (> 85 cm) in South Florida mangrove forests. In addition, soil anoxia is hypothesized to be an important stressor in lagoonal-bay estuaries and marsh-mangrove ecotones with minimal tidal exchange.     

CENTROCERAS INTERNITENS N. SP. (RHODOPHYCEAE,CERAMIACEAE) FROM THE WESTERN TROPICAL NORTH ATLANTIC OCEAN1

Centroceras internitens n. sp. (Rhodophyceae, Ceramiaceae) was found in the Florida Keys and Bermuda only as an epiphyte on Ceramium nitens (C. Agardh) J. Agardh. It is described on the basis of many collections, including an abundance of reproductive material representing all stages of the life history. Laboratory culture has not been successful. The type locality is a well-known limestone platform on the Atlantic Ocean side of West Summerland Key, Florida Keys. In addition to living material, C. internitens was found on eight herbarium specimens of Ceramium nitens at the United States National Museum, thereby establishing records of its occurrence throughout the Caribbean Sea and dating back to 1887.