. Bulletin of the Natural History Museum Zoology. REVISION OF SIMOCEPHALUS DAPHNIIDAE 33. Fig. 34 S. congener, parthenogenetic female. A. postabdominal claw, B, lateral view. Diagnosis. Measurements. 9 9 ad.: Female (Fig. 38). General body shape ovoid. Frons with small obtuse prominence not separated above and below by depressions. Dorso-posterior valve prominence distinct, separated above and below by deep depressions. Dorsal margin with denticles. Diameter of circle inscribed in it small. Proximal and distal supra-anal angles small, embayments of postabdomen shallow, proximal angl
. Bulletin of the Natural History Museum Zoology. REVISION OF SIMOCEPHALUS DAPHNIIDAE 33. Fig. 34 S. congener, parthenogenetic female. A. postabdominal claw, B, lateral view. Diagnosis. Measurements. 9 9 ad.: Female (Fig. 38). General body shape ovoid. Frons with small obtuse prominence not separated above and below by depressions. Dorso-posterior valve prominence distinct, separated above and below by deep depressions. Dorsal margin with denticles. Diameter of circle inscribed in it small. Proximal and distal supra-anal angles small, embayments of postabdomen shallow, proximal angle rounded. Distribution. (Fig. 32) , Canada. Remarks. The original description of this species is not provided with an illustration (Herrick, 1884). It is evident from the descrip- tion that it is closely related with S. acutirostratus. 'The spine is as in S. americanus' (S. serrulatus) and 'the head is produced below the eyes in an angle, like a right angle, which is not spiny'. I had serious doubt about the taxonomical state of this taxon (Orlova- Bienkowskaja, 1993), because there were no other records of S. (acutirostratus) species group from North America. The examina- tion of specimens from Canada has shown that they belong to this group and differ from S. acutirostratus, S. victoriensis and S. brehmi in the shape of the dorso-posterior valve angle. Obviously, they belong to S. rostratus. There is one undescribed species of S. (acutirostratus) group in North America. I have about forty specimens of this species from California and Washington, but I do not name this new species. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Natural History Museum (London). Andover : Intercept
Size: 1372px × 1820px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bhlconsortium, bookcentury1900, bookcollectionbiodiversity, bookl
