Different Symptoms for Different Causes of Pain. Orchialgia caused by infection is severe and even in cutting pain accompanied by fever with chilliness, reddened and swollen scrotum, and apparent tenderness. Most bacterial orchitis is caused by adjacent epididymal inflammation, so it is also called epididymo-orchitis.
From Wikipedia, the free encyclopedia. Agnatha (Greek, no jaws) is a superclass of jawless fish in the phylum Chordata, subphylum Vertebrata, consisting of both present (cyclostomes) and extinct (conodonts and ostracoderms) species. The group excludes all vertebrates with jaws, known as gnathostomes.he Agnatha are ectothermic or cold blooded, with a cartilaginous skeleton, and the heart contains 2 chambers.
Idealized body plan of the Agnatha. Agnatha (Greek, no jaws), often considered a superclass within the subphylum Vertebrata, comprises the jawless fishâthe oldest known vertebrates. The two extant groups of jawless fish (sometimes called cyclostomes) are the lampreys and the hagfish. They are descendants of extinct armored agnathans that were once widespread and were the precursors also of the jawed vertebrates, which includes the bony fish, tetrapods, and humans.