Astronesthes richardsoni chin is ribbon-like and lacks a bulb or swelling at its tip. The dorsal fin has 12 to 14 soft rays and the anal fin has 13 to 18. The origin of the dorsal fin is behind the insertion of the pelvic fins. There is a dorsal adipose fin anterior to the caudal peduncle, and a small ventral adipose fin just anterior to the anus. There are two rows of photophores (luminous spots) on each side of the underside of the fish, numerous other photophores on the head and body and a luminous patch on the edge of the preoperculum;
Caudal cell mass the inhibition of critical elements of morphogenesis, that are found in the extracellular matrix, or due to the presence of an abnormal hox gene. These abnormalities can be predicted ahead of time using ultrasound. Caudal cell mass In humans and other mammals, the caudal cell mass (sometimes tail bud in humans) is the aggregate of undifferentiated cells at the caudal end on the spine.The caudal end of the spinal cord first begins to form after primary neuralation has taken place, indicating that it develops after the cranial portion of the spinal cord has developed. Following neuralation, the caudal tail begins