Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 24 of 24

Full-Text Articles in Life Sciences

First Record Of Bonefish, Albula Vulpes, From Mississippi Coastal Waters, K.J. Cuevas, James S. Franks, M.V. Buchanan Jan 2004

First Record Of Bonefish, Albula Vulpes, From Mississippi Coastal Waters, K.J. Cuevas, James S. Franks, M.V. Buchanan

Gulf and Caribbean Research

Bonefish (Albula spp.), Family Albulidae, occur worldwide in coastal waters of tropical and warm temperate seas (Crabtree et al. 1997), and 2 species, A. vulpes and A. nemoptera, are recognized from the western Atlantic Ocean (Rivas and Warlen 1967). The normal range of A. vulpes in the western Atlantic extends from Bermuda to Brazil, including the Bahamas, Cuba, Mexico, Central America and the Antilles (Hildebrand 1963), but in US waters, A. vulpes typically occurs off south Florida (Crabtree et al. 1997). In contrast, A. nemoptera has been reported from Panama, Colombia, Venezuela, Jamaica and Hispaniola (Uyeno et al. …


A Characterization Of The Shallow-Water Coral Reefs And Associated Habitats Of Puerto Rico, Matthew S. Kendall, Curtis R. Kruer, Ken R. Buja, John D. Christensen, Ernesto Diaz, Robert A. Warner, Mark E. Monaco Jan 2004

A Characterization Of The Shallow-Water Coral Reefs And Associated Habitats Of Puerto Rico, Matthew S. Kendall, Curtis R. Kruer, Ken R. Buja, John D. Christensen, Ernesto Diaz, Robert A. Warner, Mark E. Monaco

Gulf and Caribbean Research

We mapped bottom types and shelf zones of 1600 km2 or about one fourth of Puerto Rico’s insular shelf from the shoreline to the shelf edge. Overall map accuracy for these bottom types is estimated as 93.6% correct. Maps were produced through visual interpretation of benthic features using orthorectified aerial photographs within a Geographic Information System with customizable software. The maps are one component of an integrated mapping and monitoring program underway by NOAA and its partners in the US Coral Reef Task Force to assess all US reef ecosystems. Maps are currently being used to enhance coastal research …


Artificial Reef Matrix Structures (Arms): An Inexpensive And Effective Method For Collecting Coral Reef-Associated Invertebrates, Todd L. Zimmerman, Joel W. Martin Jan 2004

Artificial Reef Matrix Structures (Arms): An Inexpensive And Effective Method For Collecting Coral Reef-Associated Invertebrates, Todd L. Zimmerman, Joel W. Martin

Gulf and Caribbean Research

Collecting reef-associated invertebrates usually involves disturbance of the reef area, often damaging the habitat and sometimes damaging live corals. We introduce a nondestructive, inexpensive, and effective method for collecting coral reef-associated invertebrates using approximations of small coral heads constructed of concrete, PVC pipes, nylon cleaning pads, and other materials easily obtainable in most tropical (coral-rich) countries. An example showing the effectiveness of the method is presented based on fieldwork in the eastern Caribbean.


Seasonal Occurrence Of Reef-Related Medusae (Cnidaria) In The Western Caribbean Sea, Gloria Ramos, Lourdes Segura-Puertas Jan 2004

Seasonal Occurrence Of Reef-Related Medusae (Cnidaria) In The Western Caribbean Sea, Gloria Ramos, Lourdes Segura-Puertas

Gulf and Caribbean Research

Seasonal fluctuations in composition and abundance of medusae collected in a reef lagoon of the Mexican Caribbean were analyzed. Plankton samples and hydrological data were taken monthly from January to September 1994 at 2 stations: coastal and near-reef. The highest densities of medusae were recorded in March (17,687 ind/100 m3) and August (2,433 ind/100 m3) at the coastal station. Medusae were less abundant at the nearreef station, but diversity indices were higher in comparison to the coastal station. Twenty-five species (24 hydroidomedusae and 1 scyphomedusa) were identified, with Linuche unguiculata (Swartz, 1788) and Eirene lactea (Mayer, …


Formation Of A Stress-Induced Check Mark On The Otoliths Of Juvenile Fishes: Implications For Mesocosm Studies, Thomas R. Reinert, Donald M. Baltz Jan 2004

Formation Of A Stress-Induced Check Mark On The Otoliths Of Juvenile Fishes: Implications For Mesocosm Studies, Thomas R. Reinert, Donald M. Baltz

Gulf and Caribbean Research

Daily otolith increment widths of spot Leiostomus xanthurus and spotted seatrout Cynoscion nebulosus were examined experimentally in field mesocosms for 5 to 7 days in various habitat types. Daily otolith increments were used as a surrogate for daily somatic growth so that growth prior to capture and handling could be examined. For both species, possible effects of habitat types were confounded by an overall decrease in daily increment widths during the experimental period when compared to increment widths prior to capture. Several spotted seatrout inadvertently captured during mesocosm deployment provided a means for assessing if there was a significant mesocosm …


The First Larval Stage Of Microprosthema Semilaeve (Von Martens, 1872) (Crustacea: Decapoda: Stenopodidea) Obtained In The Laboratory, Joel W. Martin, Joseph W. Goy Jan 2004

The First Larval Stage Of Microprosthema Semilaeve (Von Martens, 1872) (Crustacea: Decapoda: Stenopodidea) Obtained In The Laboratory, Joel W. Martin, Joseph W. Goy

Gulf and Caribbean Research

The first larval stage of Microprosthema semilaeve (von Martens, 1872) is described from ovigerous females collected off Sombrero Key, Florida Keys, USA, and Guana Island, British Virgin Islands, Caribbean. The larvae are characterized by a broad, triangular telson bearing posterolateral spines and an “anomuran seta,” a first maxilliped that differs markedly from the very similar (to each other) second and third maxillipeds, and the presence of the first pereiopod as a swimming appendage upon hatching, as is apparently true of all stenopodidean first stage larvae. Characters of the larvae are compared to those described from the Indian Ocean by Raje …


Embryogenesis In The Dwarf Seahorse, Hippocampus Zosterae (Syngnathidae), James T. Wetzel, John P. Wourms Jan 2004

Embryogenesis In The Dwarf Seahorse, Hippocampus Zosterae (Syngnathidae), James T. Wetzel, John P. Wourms

Gulf and Caribbean Research

Embryogenesis of the dwarf seahorse, Hippocampus zosterae, was studied by scanning electron microscopy of a series of developmental stages. Stages ranged from initial cleavage of the egg through term embryos. Embryos hatch from their egg envelopes about midway through development, yet remain nestled in stromal chambers of vascularized epithelium within the male brood pouch until their yolk reserves are consumed. The difference in body shape between the pipefish and seahorse first becomes discernible during mid-development, just before hatching. At this stage, embryos begin to develop their characteristic prehensile tail in contrast to the straight body and typical caudal fin …


Stomatopoda (Crustacea: Hoplocarida) From The Shallow, Inshore Waters Of The Northern Gulf Of Mexico (Apalachicola River, Florida To Port Aransas, Texas), John M. Foster, Brent P. Thoma, Richard W. Heard Jan 2004

Stomatopoda (Crustacea: Hoplocarida) From The Shallow, Inshore Waters Of The Northern Gulf Of Mexico (Apalachicola River, Florida To Port Aransas, Texas), John M. Foster, Brent P. Thoma, Richard W. Heard

Gulf and Caribbean Research

Six species representing the order Stomatopoda are reported from the shallow, inshore waters (passes, bays, and estuaries) of the northern Gulf of Mexico limited to a depth of 10 m or less, and by the Apalachicola River (Florida) in the east and Port Aransas (Texas) in the west. With the exception of the “live bottom” gonodactylid, Neogonodactylus bredini (Manning), these predatory crustaceans usually inhabit burrows in mud, sand-mud, and sand substrata in coastal and shelf waters. The species treated in this paper are Neogonodactylus bredini (Manning), Lysiosquilla scabricauda (Lamarck), Bigelowina biminiensis (Bigelow), Coronis scolopendra Latreille, Squilla empusa Say, and Gibbesia …


Northern Range Extensions For Caprella Scaura Templeton, 1836 (Crustacea: Amphipoda: Caprellidae) On The Florida Gulf Coast And In South Carolina, John M. Foster, Richard W. Heard, David M. Knott Jan 2004

Northern Range Extensions For Caprella Scaura Templeton, 1836 (Crustacea: Amphipoda: Caprellidae) On The Florida Gulf Coast And In South Carolina, John M. Foster, Richard W. Heard, David M. Knott

Gulf and Caribbean Research

Previous northwestern Atlantic records for the caprellid amphipod Caprella scaura Templeton, 1836 were confined to St. Croix (US Virgin Islands), St. Barthélemy, and Puerto Rico, islands bordering the northern Caribbean Sea. Based on recent collections, C. scaura is now reported from the Gulf of Mexico (St. Andrew Bay, Florida) and the US east coast (Charleston Harbor, South Carolina). These constitute the first records for this apparently non-indigenous species in waters of the continental eastern United States, establishing considerable northern range extensions for C. scaura in the northwest Atlantic.


Notes On Aquarium Brood Release And Feeding Of The Opossum Pipefish, Microphis Brachyurus Lineatus, Sarah Frias-Torres Jan 2004

Notes On Aquarium Brood Release And Feeding Of The Opossum Pipefish, Microphis Brachyurus Lineatus, Sarah Frias-Torres

Gulf and Caribbean Research

The opossum pipefish, Microphis brachyurus lineatus, is a migratory syngnathid with a salmon-like life history (Frias-Torres 2002). Adults breed in freshwater and oligohaline habitats associated with emergent vegetation, mostly Panicum sp. and Polygonum sp.; breeding occurs during the wet season (May to November) (Gilmore and Hastings 1983). In southern Mexico, opossum pipefish associate with Ruppia maritima, and reproduction is year-round (Miranda-Marure et al. 2004). Pelagic juveniles are found in the Atlantic Ocean and are associated with Sargassum sp. (Böhlke and Chaplin 1968). Juveniles eventually recruit into oligohaline habitats. The species range is from Sao Paulo, Brazil, to New …


Introduction To Special Section On Research Activities At The Iztacala Campus Of The Universidad Nacional Autónoma De México, México, Mark S. Peterson, Nancy J. Brown-Peterson Jan 2004

Introduction To Special Section On Research Activities At The Iztacala Campus Of The Universidad Nacional Autónoma De México, México, Mark S. Peterson, Nancy J. Brown-Peterson

Gulf and Caribbean Research

In October 2002, we had the opportunity to initiate a long-term collaboration with colleagues from the Iztacala campus of the Universidad Autónoma de México (UNAM), whose research interests focus on coastal and nearshore fishes and decapod crustaceans of Veracruz state, Mexico. This is an undergraduate campus with a strong Biology department whose faculty also maintain research programs despite limited sources of funding and a heavy teaching load. During the course of our initial visit, we realized that there is a wealth of unpublished undergraduate student research on understudied fish species.


Overview Of Study Areas And Unam-Iztacala Student Research, Jonathan Franco-Lopez, Jose Antonio Martinez-Perez Jan 2004

Overview Of Study Areas And Unam-Iztacala Student Research, Jonathan Franco-Lopez, Jose Antonio Martinez-Perez

Gulf and Caribbean Research

The State of Veracruz is located on the east coast of Mexico and consists of many shallow marine systems such as estuaries and coastal lagoons. These estuarine systems are ecological sites of great importance due to the interactions that occur between the intertidal zones and adjacent areas. This importance is reflected in the variety of natural components present in these sites as well as the large number of species that depend on this aquatic zone, such as birds, mammals, molluscs, crustaceans and fishes. Many of the crustaceans and fishes are consumed by the local inhabitants and distributed in commercial areas …


Feeding Habits And Sexual Dimorphism Of The Violet Goby, Gobioides Broussoneti Lacepede (Pisces: Gobiidae), In The Estuarine System Of Tecolutla, Veracruz, Mexico, Sergio Mata-Cortes, Jose Antonio Martinez-Perez, Mark S. Peterson Jan 2004

Feeding Habits And Sexual Dimorphism Of The Violet Goby, Gobioides Broussoneti Lacepede (Pisces: Gobiidae), In The Estuarine System Of Tecolutla, Veracruz, Mexico, Sergio Mata-Cortes, Jose Antonio Martinez-Perez, Mark S. Peterson

Gulf and Caribbean Research

Gobioides broussoneti were sampled in Silveña estuary, a branch of the Tecolutla estuary, Veracruz, Mexico, during 2 trips made between February 1998 and June 1999 to evaluate diet and sexual dimorphism. A total of 65 G. broussoneti ranging from 49–401 mm SL (0.7–124.2 g WW) were collected. There was a 1:1.2 sex ratio in favor of females. Seven food types were noted, with filamentous algae (25.4%) and detritus (21.3%) representing the principal food types. A 24 h feeding study revealed that this species feeds continuously throughout the day. The ovaries of all female G. broussoneti contained previtellogenic oocytes, characteristic of …


Reproductive Biology Of The Opossum Pipefish, Microphis Brachyurus Lineatus, In Tecolutla Estuary, Veracruz, Mexico, Martha Edith Miranda-Marure, Jose Antonio Martinez-Perez, Nancy J. Brown-Peterson Jan 2004

Reproductive Biology Of The Opossum Pipefish, Microphis Brachyurus Lineatus, In Tecolutla Estuary, Veracruz, Mexico, Martha Edith Miranda-Marure, Jose Antonio Martinez-Perez, Nancy J. Brown-Peterson

Gulf and Caribbean Research

The reproductive biology of the opossum pipefish, Microphis brachyurus lineatus, was investigated in Tecolutla estuary, Veracruz, Mexico, to determine sex ratio, size at maturity, gonadal and brood pouch histology, reproductive seasonality, and fecundity of this little-known syngnathid. A total of 345 fish were collected between 1995–1998, with an overall sex ratio of 1:1.35 favoring females. Brooding males made up 45% of the population, resulting in an operational sex ratio of 1:2.45 heavily favoring females. All males > 90 mm SL were considered sexually mature, as this was the size at which the brood pouch was clearly developed. Females > 110 mm …


Helminths From Dormitator Maculatus (Pisces: Eleotridae) In Alvarado Lagoon, Veracruz, Mexico, And Supplemental Data For Clinostomum Complanatum Rudolphi, 1814 From Egretta Caerulea (Aves: Ardeidae), Jesus Montoya-Mendoza, Rafael Chavez-Lopez, Jonathan Franco-Lopez Jan 2004

Helminths From Dormitator Maculatus (Pisces: Eleotridae) In Alvarado Lagoon, Veracruz, Mexico, And Supplemental Data For Clinostomum Complanatum Rudolphi, 1814 From Egretta Caerulea (Aves: Ardeidae), Jesus Montoya-Mendoza, Rafael Chavez-Lopez, Jonathan Franco-Lopez

Gulf and Caribbean Research

Fishes are important hosts of helminths with aquatic life stages, yet little information is available on host-parasite relationships in tropical low salinity ecosystems. In this paper we report helminth parasites of the fat sleeper, Dormitator maculatus, in the Alvarado lagoon system, Veracruz. Mexico. Four parasite species were recorded from D. maculatus, including trematode metacercariae of Clinostomum complanatum, as well as nematode larvae of Spyroxis sp. and Camallanus sp. and adults of Neochinorhynchus golvani. In addition, we obtained adult C. complanatum from the esophagus of the little blue heron, Egretta caerulea. Dormitator maculatus is a new …


Predators And The Distribution And Abundance Of Blennies On Offshore Petroleum Platforms, Tommy J. Rauch Jan 2004

Predators And The Distribution And Abundance Of Blennies On Offshore Petroleum Platforms, Tommy J. Rauch

Gulf and Caribbean Research

Predation may be important in structuring fish assemblages but studies of the intensity of predation on marine fish assemblages are uncommon. Predator avoidance behavior was used to identify the predators of an assemblage of blennies found on offshore petroleum platforms in the northern Gulf of Mexico. The distribution of predators was then compared with the distribution of 3 species of blennies to see if predation intensity was related to the vertical zonation of blennies. Predator approaches and blenniid activity were compared in low and high surface current events. Results did not support a hypothesis of predation controlling the distribution and …


Studies On The Crustacea Of The Turks And Caicos Islands, British West Indies. V. Records Of Mysids From Pine Cay, Fort George Cay, Water Cay, And Adjacent Waters, W. Wayne Price, Richard W. Heard Jan 2004

Studies On The Crustacea Of The Turks And Caicos Islands, British West Indies. V. Records Of Mysids From Pine Cay, Fort George Cay, Water Cay, And Adjacent Waters, W. Wayne Price, Richard W. Heard

Gulf and Caribbean Research

Only 2 species of mysids, Heteromysis spottei and Stygiomysis clarkei, have been previously reported from the Turks and Caicos Islands. Between 1988 and 1990, 21 species of mysids were collected from reef (to 38 m) and shallow non-reef habitats surrounding Pine Cay, Fort George Cay, and Water Cay, Turks and Caicos Islands. One species collected, Anchialina typica, is distributed throughout tropical and subtropical seas. Twelve species (Bowmaniella johnsoni, Dioptromysis paucispinosa, Heteromysis bermudensis, H. guitarti, H. mayana, Mysidium columbiae, M. gracile, M. integrum, Mysidopsis bispinulata, M. brattstromei, Parvimysis …


Spatial Patterns Of Estuarine Habitat Type Use And Temporal Patterns In Abundance Of Juvenile Permit, Trachinotus Falcatus, In Charlotte Harbor, Florida, Aaron J. Adams, David A. Blewett Jan 2004

Spatial Patterns Of Estuarine Habitat Type Use And Temporal Patterns In Abundance Of Juvenile Permit, Trachinotus Falcatus, In Charlotte Harbor, Florida, Aaron J. Adams, David A. Blewett

Gulf and Caribbean Research

The life history of many marine fishes is a 2-phase cycle: juveniles and adults make up a demersal phase, whereas larvae are planktonic. Determining ontogenetic patterns of habitat type use of the demersal phase has important management and habitat conservation implications for species that use coastal habitat types as juveniles. Juvenile permit, Trachinotus falcatus, are presumed to be limited to beaches exposed to open ocean, but few studies have addressed juvenile permit use of estuarine habitat types. Ten years of fisheries-independent monitoring data from a subtropical estuary were analyzed to determine habitat type use patterns and seasonality of juvenile …


Gonadal Development And Sexual Dimorphism Of Gobiomorus Dormitor From The Estuarine System Of Tecolutla, Veracruz, Mexico, Raquel Hernandez-Saavedra, Jose Antonio Martinez-Perez, Nancy J. Brown-Peterson, Mark S. Peterson Jan 2004

Gonadal Development And Sexual Dimorphism Of Gobiomorus Dormitor From The Estuarine System Of Tecolutla, Veracruz, Mexico, Raquel Hernandez-Saavedra, Jose Antonio Martinez-Perez, Nancy J. Brown-Peterson, Mark S. Peterson

Gulf and Caribbean Research

The bigmouth sleeper, Gobiomorus dormitor, is a benthic, euryhaline species, and is very abundant in river mouths, coastal lagoons, and sites away from marine influence from south Florida to Dutch Guyana. There are few studies of its life history, ecology, and abundance, particularly within Mexican waters. Nine trips to Tecolutla estuary, Veracruz, Mexico, were taken between October 1995 and May 1998 to estimate the gonadal development and sexual dimorphism of G. dormitor. A total of 94 individuals ranging from 15–260 mm SL and 0.05–181 g were captured. Seventy-two specimens were adults (60 females, 12 males) and 22 were …


Range Extensions And Review Of The Caprellid Amphipods (Crustacea: Amphipoda: Caprellidae) From The Shallow, Coastal Waters From The Suwanee River, Florida, To Port Aransas, Texas, With An Illustrated Key, John M. Foster, Brent P. Thoma, Richard W. Heard Jan 2004

Range Extensions And Review Of The Caprellid Amphipods (Crustacea: Amphipoda: Caprellidae) From The Shallow, Coastal Waters From The Suwanee River, Florida, To Port Aransas, Texas, With An Illustrated Key, John M. Foster, Brent P. Thoma, Richard W. Heard

Gulf and Caribbean Research

Eight species of the amphipod family Caprellidae sensu Myers and Lowry, 2003 are currently known to occur in the shallow, near shore waters of the northern Gulf of Mexico (GOM), from the Suwannee River, Florida, to Port Aransas, Texas, and to depths of 10 m. They include: Phtisica marina, Hemiaegina minuta, Paracaprella pusilla, Paracaprella tenuis, Deutella incerta, Caprella equilibra, Caprella penantis, and Caprella scaura. Another species, Caprella andreae, is also suspected to occur in this region due to its close association with sea turtles, which nest on the sand beaches of …


Morphological Characteristics Of The Carapace Of The Hawksbill Turtle, Eretmochelys Imbricata, From Cuban Waters, Mari Kobayashi Jan 2004

Morphological Characteristics Of The Carapace Of The Hawksbill Turtle, Eretmochelys Imbricata, From Cuban Waters, Mari Kobayashi

Gulf and Caribbean Research

Hawksbill turtles, Eretmochelys imbricata (Linnaeus, 1766), from Cuban waters of the Caribbean were analyzed to determine the relationships between straight carapace length (SCL) and either straight carapace width (SCW) or body weight (Wt). The regression equations were SCW = 0.9136(SCL)0.951 (R2 = 0.923, n = 315) and Wt = 4.17 x 10–4(SCL)2.68 (R2 = 0.798, n = 289), respectively. The regression equations between the first costal width (C1W) and either SCW or Wt were SCW = 3.223(C1W)0.847 (R2 = 0.919, n = 156) and Wt = 1.416 x 10–2(C1W)2.426 …


A New Species Of Protanaissus Sieg, 1982 (Crustacea: Tanaidacea: Peracarida), From South Florida, Kim Larsen, Richard W. Heard Jan 2004

A New Species Of Protanaissus Sieg, 1982 (Crustacea: Tanaidacea: Peracarida), From South Florida, Kim Larsen, Richard W. Heard

Gulf and Caribbean Research

A new nototanaid species, Protanaissus floridensis, is described from Biscayne Bay in southeastern Florida. Specimens were collected at a depth of 7 m in muddy sand substrata with associated aquatic vegetation (Thalassia testudinum). Protanaissus floridensis, which represents only the 4th species referable to the genus, is the first species of Protanaissus Sieg, 1982, known from the northern hemisphere. The new species is distinguished from the other 3 species of Protanaissus by 1) the dactylus of pereopod 1 shorter than combined length of propodus and carpus, 2) the dactylus of the cheliped with proximal spine on inner …


Trophic Comparison Of Two Species Of Needlefish (Belonidae) In The Alvarado Lagoonal System, Veracruz, Mexico, Daniel Arceo-Carranza, Jonathan Franco-Lopez, Gretchen L. Waggy, Rafael Chavez-Lopez Jan 2004

Trophic Comparison Of Two Species Of Needlefish (Belonidae) In The Alvarado Lagoonal System, Veracruz, Mexico, Daniel Arceo-Carranza, Jonathan Franco-Lopez, Gretchen L. Waggy, Rafael Chavez-Lopez

Gulf and Caribbean Research

We compared the diets of Atlantic needlefish, Strongylura marina, and redfin needlefish, Strongylura notata, in the Alvarado lagoonal system, Veracruz, Mexico, and analyzed diet breadth and trophic overlap between the species. All fishes were collected monthly from June 2000 to July 2001 at twelve sampling stations. A total of 74 intestinal tracts from S. marina were analyzed. The diet of S. marina consisted of 25 prey types with fish being the dominate prey. In eighty-nine digestive tracts examined from S. notata, the diet consisted of 29 prey types with the dominant prey including fishes, penaeid shrimp, polychaetes, …


Reproductive Structures And Early Life History Of The Gulf Toadfish, Opsanus Beta, In The Tecolutla Estuary, Veracruz, Mexico, Alfredo Gallardo-Torres, Jose Antonio Martinez-Perez, Brian J. Lezina Jan 2004

Reproductive Structures And Early Life History Of The Gulf Toadfish, Opsanus Beta, In The Tecolutla Estuary, Veracruz, Mexico, Alfredo Gallardo-Torres, Jose Antonio Martinez-Perez, Brian J. Lezina

Gulf and Caribbean Research

Although the Gulf toadfish, Opsanus beta, is an abundant member of the nearshore Gulf of Mexico ichthyofaunal assemblage, little information exists regarding the ecology of the species, especially for southern Gulf of Mexico populations. We added to the existing knowledge of this species by describing the reproductive structures and examining the early life history of this species in the Tecolutla estuary, Mexico. Macro- and microscopic examination of 7 males showed spermatogenesis to be similar to other teleost species except for the occurrence of biflagellate spermatozoa. Histological examination of the male accessory gland showed 3 tissue layers, but their functions …