(redirected from nephridia)
Also found in: Dictionary, Encyclopedia.
Related to nephridia: Malpighian tubules, parapodia


, pl.


(ne-frid'ē-ŭm, -ă),
One of the paired, segmentally arranged excretory tubules of invertebrates such as the annelids.
[G. nephros, kidney, + Mod. L. -idium, dim. suffix, fr. G. -idion]
Farlex Partner Medical Dictionary © Farlex 2012


n. pl. nephrid·ia (-ē-ə)
1. A tubular excretory organ in many invertebrates, such as mollusks and earthworms.
2. The excretory organ of a vertebrate embryo from which the kidney develops.

ne·phrid′i·al adj.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.


(pl. nephridia) a primitive excretory organ present in many invertebrates (e.g. the earthworm) in the form of a tube which opens at one end to the exterior. The other end may open into the COELOM or may terminate in a FLAME CELL.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005
References in periodicals archive ?
One or two pairs of anterior nephridia, in 6/7-8/9, with compact spindle-shaped postseptale (up to 90 [micro]m x 40 [micro]m) tapering into short (35 [micro]m) ectal duct in its posterior end.
In particular, Acidovorax-like symbionts of earthworms colonize the nephridia (excretory organs) and degrade peptides and amino acids, facilitating the reabsorption of nitrogen by the worms before it is excreted as waste (Schramm a al., 2003).
Benham (1888: 72) reported on a specimen from an unknown type locality, with two pairs of nephridia per segment and the gizzard in segment 6, and named it Brachydrilus [sp.].
Oblique transverse sections, approximately 5 mm thick and including mantle, gills, gonad, digestive gland, nephridia, and foot were taken from each specimen.
These cells appear to be the larval mesoderm, which we suspect will form larval muscles such as the dorsal levators, and possibly the larval nephridia. At the opposite side of the archenteron, the surface of the embryo protrudes just below the mesodermal pockets (Fig.
Nephridia, in posterior segments two pairs per segment, coiled; the dorsal pair larger and the ventral smaller, this varying between segments, in some the dorsal smaller and the ventral larger.
Remacha-Trivino (2002) found a parallel disorganization and subsequent reorganization of nephridia and gonads in S.
Based on nephridia characteristics, Korniushin (1998) suggested that all African Sphaerium spp.
Tissue samples were embedded in Paraplast, and oblique transverse sections, approximately 5-mm thick, were taken from each specimen including mantle, gills, gonad, digestive gland, nephridia and foot.
Females with single pair of ciliated ducts (oviducts, nephridia, or both) opening on ventral surface of segment 11, with external opening only 10 [micro]m in diameter (Fig.
They mature to metaphase of meiosis I in the coelomic fluid, are collected by the nephridia, and spawned (Daly, 1972).
Antidiuretic and diuretic activities of FMRFamide and GDPFLRFamide respectively have been demonstrated in nephridia of a leech (Salzet et al., 1994).