Walter J. Harman

Ecophenotypic Variation in Setae of Naididae (Oligochaeta)

Specimens from a clone of Pristina aequiseta Bourne were found to lose and regain giant setae characteristic of the species when cultured in varying ionic concentrations of an artificial pond water. Pristina foreli (Piguet) is declared a junior synonym of P. aequiseta. Species of Dero, Nais, and Pristina were found to produce morphologically different setae in response to environmental changes in field and laboratory situations.

Capilloventer atlanticus gen. et sp.n., a member of a new family of marine Oligochaeta from Brazil

Specimens of a previously undescribed oligochaete from the Bay of Rio de Janeiro, Brazil were determined to belong to a new family of microdiles within the order Tubificida, suborder Enchytraeina. The specimens are characterized by dorsal and ventral hair setae, spermathecae in VII, testes in XI, ovaries in XII, and a clitellum. The number of primitive characters present in the new species indicate that it is a primitive member of the order that diverged early from the evolutionary line leading to the Enchytraeidae.

New Species of Oligochaeta (Naididae) with Additional Distributional Records from Oklahoma and Texas

The distribution of aquatic oligochaetes in Texas and Oklahoma is discussed. Nais magnaseta is described from Texas and Pristina unidentata is described from Oklahoma. Morphometric characteristics of specimens from these states are compared with those from other regions. Among several collections of aquatic oligochaetes obtained over the years, or sent to me from Oklahoma and Texas, there appear two undescribed species and some distributional data worthy of record. Of the 15 species discussed, 11 are new to the fauna of this area and most of these extend the known range into the southwestern United States.

THE AQUATIC OLIGOCHAETA (AEOLOSOMATIDAE, OPISTOCYSTIDAE, NAIDIDAE) OF CENTRAL AMERICA

Twenty species of aquatic oligochaetes are reported from Costa Rica, El Salvador, Guatemala, Nicaragua, and Honduras. Species are in the families Aeolosomatidae, Opistocystidae, and Naididae. Setal measurements are cited for each species and compared with measurements from other parts of the range. Seven of the species are cosmopolitan and seven show neotropical affinities, while only two show nearctic relationships. Two species, Pristina menoni and Dero plumosa, are reported for the first time from the Western Hemisphere. The Central American republics have very few recorded species of aquatic oligochaetes, although some of the terrestrial species have been studied. Over a decade has been spent in gathering these few collections, and since no additional effort is anticipated in the near future, it is deemed appropriate to publish these records.

AQUATIC OLIGOCHAETA NEW TO NORTH AMERICA WITH SOME FURTHER RECORDS OF SPECIES FROM TEXAS

Presented herein are accounts of 12 species of Naididae and three of Tubificidae now known to occur in western Texas. Dero (D.) pectinata and Pristina americana are new to the North American fauna, having previously been reported only from neotropical regions. Nais communis, N. variabilis, Para- nais litoralis, Pristina synclites, and Monopylephorus sp. are new to Texas. Chae- togaster diastrophus, Dero (Aulophorus) furcata, Dero (D.) digitata, Pristina aequiseta, P. leidyi, Slavina appendiculata, Limnodrilus hoffmeisteri, and L. udekemianus are known from elsewhere in the state, but their presence in western Texas considerably extends their known ranges.

Dero (Aulophorus) Intermedia Nomen Novum for Aulophorus Pectinatus Stephenson, 1931 (Oligochaeta: Naididae)

Aulophorus pectinatus Stephenson, 1931, is renamed Dero (Aulophorus) intermedia nomen novum because of its congeneric relationship with Dero pectinata Aiyer, 1930. The species is recorded from Pennsylvania and Louisiana in North America.