Edward Avery Richmond (1887-1970)

Memorial of Dr. E.A. Richmond

Marine Fishes of Panama as Related to the Canal

Recent papers by Eskinazi, compared to studies made on the Texas and Louisiana coasts 35 to 45 years ago and on the south Atlantic coast 15 years ago, show remarkable similarities of the estuarine fishes of northeastern Brazil and the northern Gulf of Mexico. Forty-five of 48 families of the two areas are in common and about 35% of the species are in common. On the west coast even greater correspondence might be expected between fishes of Peru and southern California, were it not for the restriction of tropical fishes by the Humboldt and California currents. When the lithospheric plate under North America pulled away from Pangaea, strong swimmers and pelagic fishes maintained connections. Thus, the marine fishes have had strong connections for the last 70 million years. Further, the Pacific and Atlantic faunas were connected until the mid-Pliocene when Isthmus America became continuous about 5.7 million years ago. Marine euryhaline fishes are much more abundant than their freshwater counterparts. Thus large numbers of marine fishes are found in the fresh waters of Panama. One hundred thirty-seven (137) marine fishes have been found there and 57 species have taken up more or less permanent residence. No freshwater fish have taken up residence in the seas of Panama. The freshwater fishes of Central America came from the south and their movement has been very slow. Isthmus America was a ridged mountainous area with short, small rivers and small basins. The estuaries were small or nonexistent. Thus, one avenue for spread of fishes from fresh water was generally nonexistent. There are 32 river basins in Panama and fish have little access from one to the other. So the river basins have an insular aspect. The Canal runs through only three river basins. There are generally no problems to the passage of freshwater fishes in the Canal but they are stopped by even low salinity and, if back pumping becomes necessary to maintain the lakes used in the operation of the locks, most freshwater fishes will not traverse the Canal. Thus, it may be said that there is little chance of transfer of freshwater fishes from one coast to the other. However, the tarpon has already crossed the isthmus and eight other species, including blennies, gobies and pipefishes, have made the passage according to ichthyological collectors. Actually only four fishes are indubitable crossers. Back pumping will increase the potentiality a great deal but no foreign process of gene flow or heredity other than what is present all over the world today and which was present when the Pacifi\u27c and Atlantic were connected, is to be expected. Thus a sea level canal would present a new situation but nothing that could be antibiological or deadly

Marine Fishes of Panama as Related to the Canal

Recent papers by Eskinazi, compared to studies made on the Texas and Louisiana coasts 35 to 45 years ago and on the south Atlantic coast 15 years ago, show remarkable similarities of the estuarine fishes of northeastern Brazil and the northern Gulf of Mexico. Forty-five of 48 families of the two areas are in common and about 35% of the species are in common. On the west coast even greater correspondence might be expected between fishes of Peru and southern California, were it not for the restriction of tropical fishes by the Humboldt and California currents. When the lithospheric plate under North America pulled away from Pangaea, strong swimmers and pelagic fishes maintained connections. Thus, the marine fishes have had strong connections for the last 70 million years. Further, the Pacific and Atlantic faunas were connected until the mid-Pliocene when Isthmus America became continuous about 5.7 million years ago. Marine euryhaline fishes are much more abundant than their freshwater counterparts. Thus large numbers of marine fishes are found in the fresh waters of Panama. One hundred thirty-seven (137) marine fishes have been found there and 57 species have taken up more or less permanent residence. No freshwater fish have taken up residence in the seas of Panama. The freshwater fishes of Central America came from the south and their movement has been very slow. Isthmus America was a ridged mountainous area with short, small rivers and small basins. The estuaries were small or nonexistent. Thus, one avenue for spread of fishes from fresh water was generally nonexistent. There are 32 river basins in Panama and fish have little access from one to the other. So the river basins have an insular aspect. The Canal runs through only three river basins. There are generally no problems to the passage of freshwater fishes in the Canal but they are stopped by even low salinity and, if back pumping becomes necessary to maintain the lakes used in the operation of the locks, most freshwater fishes will not traverse the Canal. Thus, it may be said that there is little chance of transfer of freshwater fishes from one coast to the other. However, the tarpon has already crossed the isthmus and eight other species, including blennies, gobies and pipefishes, have made the passage according to ichthyological collectors. Actually only four fishes are indubitable crossers. Back pumping will increase the potentiality a great deal but no foreign process of gene flow or heredity other than what is present all over the world today and which was present when the Pacifi\u27c and Atlantic were connected, is to be expected. Thus a sea level canal would present a new situation but nothing that could be antibiological or deadly

Notes on Sea Beach Ecology. Food Sources on Sandy Beaches and Localized Diatom Blooms Bordering Gulf Beaches

Food production along sandy beaches is much different from that of rocky beaches. No large algae grow on sand beaches. Small filamentous green algae find footholds upon molluscs, mole crabs, strands of Leptogorgia and logs. Basic food along the sand beach is made up of diatoms, bacteria, unicellular algae and detritus; diatoms are probably the most abundant autotrophic organism; the beach bacteria are largely heterotrophic. Most food on sandy beaches comes from the sea. The sandy shore seems to be barren, but it swarms with plant and animal life. Food production has a seasonal aspect. Food strands more abundantly on sandy beaches because the force of water returning to the sea is much less than that coming in. Beach materials are concentrated in a strand line. All organic materials are returned to the food cycle. Beached animal remains are consumed immediately until their breakdown products ooze away to enrich the sand substrata. The materialof logs may not be redistributed until a number of years have passed. Food producing algae are diatoms, green algae, peridinians and blue-greens. Many of them are quite small and must be detected by bacteriological methods. They are probably quite significant. Food production from autotrophic algae appears to be relatively steady compared to drifting materials, which may vary enormously. Various types of food drift in as a result of dinoflagellate blooms, catastrophic cold kills and stranding cetaceans. Seasonal drifting materials such as sargassum, Leptogorgia and jellyfish come in at particular times of the year. The river mouth floods bring in material. The artificial jetsam of ships washes up on the beaches. Nutrients and salts are also concentrated on beaches from organic remains. As a result, a type of beach-hugging planktonic bloom has been noted on the Texas coast when the sea is calm following heavy rains. It consists of a yellowish-brown conglomeration of diatoms of the species Chaetoceras sp., 15 to 20 feet wide along the shore for many, many miles. It follows heavy rains and the event is parallel to some aspects of the Florida red tide which occurs in calm weather, often following heavy rains, which are thought to bring chelating substances from the land

Specific Names of the Atlantic American White Shrimp (Family Penaeidae)

Penaeid shrimp are of special interest to zoologists for several reasons, one being the fact that they are unique among the decapod Crustacea in having a nauplius larval stage, which is otherwise found only in lower groups. The shrimp catch of the south Atlantic and Gulf coasts in 1360 amounted to one-fifth of the total value of all fishery products of the United States (Power, 1961), and the shrimp fishery is the most valuable one in the country. The catch depends almost wholly upon three species, Penaeus aztecus Ives, P. duorarum Burkenroad and P. setiferus (Linnaeus) , according to current usage. Up to about fifteen years ago the whole fishery depended upon the latter species, the North American white Because of their commercial importance, the penaeid shrimp are being studied increasingly in the Americas and other parts of the world. The literature, museum records and certain other information show that the name Penaeaeus setiferus has been misapplied for the past twenty-six years. The matter should be rectified now rather than later. The questions involved depend upon established rules of zoological nomenclature. The following account will be easily understood if it is remembered that there are two species of Atlantic American white shrimp. This fact was ascertained by Burkenroad (1936) and prior to that time all workers assumed that there was only one species, which was referred to uniformly as Pelzaelcs setiferus (Linnaeus). The northern species has been recorded only from the continent of North America. The southern species has been recorded throughout much of the West Indies and the east coasts of Middle and South America to southern Brazil

Studies of the Southern Oyster Borer, Thais haemastoma

Original work was carried on at the U.S. Bureau of Fisheries Laboratory on Apalachicola Bay from August 1935 to April 1936. Since then observations have been made in Texas, Louisiana and Mississippi. Five papers on specific aspects of the biology of the animal have been written since on this and other predatory gastropods. Here all commentaries are drawn together and unpublished matter is presented. The name Thais haemastoma is used because separations based upon the rugosity of the shells do not hold up. Perfectly smooth and very rugose specimens are found in the same bays, with various shell characteristics being related to various oyster reefs on which they grow. Radular movement is by the band-over-pulley method suggested by Husley (1853), Herrick (1906) Gunter (1936) and Carriker (1943). Evidence is presented showing that Thais can kill oysters without mechanical injury, presumably by some paralytic material. About one-third of the oysters are opened by large Thais without any boring whatsoever. Smaller Thais are more prone to bore complete holes into the shell cavity of the prey. In Apalachicola Bay large Thais may eat one oyster about every 8 days and it was calculated that on St. Vincent’s Bar 24 million adult oysters could be killed in a year. The resting gonads consist of a thin layer of tissue on the body over the liver and they are lavender-grey in the males and yellowish-orange in the females. They begin to thicken in January and the color intensifies. Egg laying takes place from April to July on the Gulf coast. No young or small Thais were seen in Apalachicola Bay probably because of heavy freshwater drainage in the springs of 1934 and 1935. Several hundred Thais were measured and each month the length frequency mode was at 80.0 mm. The largest known specimen of Thais, a Louisiana specimen, was 103 mm long. A heavy kill of Thais took place in the spring of 1935 and no adults survived in Apalachicola Bay except on Hiles’ Bar near Indian Pass, which is close to the ocean. The Thais seemed to perish when salinity dropped to 9‰ and stayed that way for several weeks. Both oysters and mussels survived at salinities lower than Thais could withstand. Thais shells are extremely hard and are difficult to break with a hammer. Nevertheless, they are cracked by stone crabs. They are also invaded by commensals such as the boring clam Diplothyra smithii, the annelid worm Polydora websteri, and the boring sponge Cliona. In Louisiana a so-called conch line was established by St. Amant (1938) when it was found that adult conchs did not get much beyond the area n Barataria Bay where the salinity fell to around 20‰. This was confirmed later by J. G. Mackin and Gunter at about 18‰, but has not been published. It has also been found that baby conchs are found landward of this line. It was found by experiments that conchs were generally killed by water registering 9‰ salinity and, additionally, that snails taken from low-salinity water survived transfer to still lower salinities or lived longer even in lethally low salinities than those coming from higher salinities. Attempts to trap conchs on oyster beds were unsuccessful because no baits more attractive than the surrounding oysters and mussels could be found. The conchs’ activity stopped at temperatures of 10°C and below

Studies of the Southern Oyster Borer, Thais haemastoma

Original work was carried on at the U.S. Bureau of Fisheries Laboratory on Apalachicola Bay from August 1935 to April 1936. Since then observations have been made in Texas, Louisiana and Mississippi. Five papers on specific aspects of the biology of the animal have been written since on this and other predatory gastropods. Here all commentaries are drawn together and unpublished matter is presented. The name Thais haemastoma is used because separations based upon the rugosity of the shells do not hold up. Perfectly smooth and very rugose specimens are found in the same bays, with various shell characteristics being related to various oyster reefs on which they grow. Radular movement is by the band-over-pulley method suggested by Husley (1853), Herrick (1906) Gunter (1936) and Carriker (1943). Evidence is presented showing that Thais can kill oysters without mechanical injury, presumably by some paralytic material. About one-third of the oysters are opened by large Thais without any boring whatsoever. Smaller Thais are more prone to bore complete holes into the shell cavity of the prey. In Apalachicola Bay large Thais may eat one oyster about every 8 days and it was calculated that on St. Vincent’s Bar 24 million adult oysters could be killed in a year. The resting gonads consist of a thin layer of tissue on the body over the liver and they are lavender-grey in the males and yellowish-orange in the females. They begin to thicken in January and the color intensifies. Egg laying takes place from April to July on the Gulf coast. No young or small Thais were seen in Apalachicola Bay probably because of heavy freshwater drainage in the springs of 1934 and 1935. Several hundred Thais were measured and each month the length frequency mode was at 80.0 mm. The largest known specimen of Thais, a Louisiana specimen, was 103 mm long. A heavy kill of Thais took place in the spring of 1935 and no adults survived in Apalachicola Bay except on Hiles’ Bar near Indian Pass, which is close to the ocean. The Thais seemed to perish when salinity dropped to 9‰ and stayed that way for several weeks. Both oysters and mussels survived at salinities lower than Thais could withstand. Thais shells are extremely hard and are difficult to break with a hammer. Nevertheless, they are cracked by stone crabs. They are also invaded by commensals such as the boring clam Diplothyra smithii, the annelid worm Polydora websteri, and the boring sponge Cliona. In Louisiana a so-called conch line was established by St. Amant (1938) when it was found that adult conchs did not get much beyond the area n Barataria Bay where the salinity fell to around 20‰. This was confirmed later by J. G. Mackin and Gunter at about 18‰, but has not been published. It has also been found that baby conchs are found landward of this line. It was found by experiments that conchs were generally killed by water registering 9‰ salinity and, additionally, that snails taken from low-salinity water survived transfer to still lower salinities or lived longer even in lethally low salinities than those coming from higher salinities. Attempts to trap conchs on oyster beds were unsuccessful because no baits more attractive than the surrounding oysters and mussels could be found. The conchs’ activity stopped at temperatures of 10°C and below

Harry J. Bennett (1904-1983)

Memorial of Harry J. Bennett, Louisiana State University

Reply to Dr. L.B. Holthuis on the Names of White Shrimp

As an explanation to the reader it should be stated that my paper was submitted to Doctor Holthuis for Crustaceana. He asked me to withdraw it and I did so saying that I would publish it elsewhere. He then asked me to publish his remarks along with it, to which I agreed, and they are given above. However, his interpretations and ideas in this instance are contrary to the International Code of Zoological Nomenclature. Therefore, I have prepared the following rebuttal

Harry J. Bennett (1904-1983)

Memorial of Harry J. Bennett, Louisiana State University