Finally, more studies of aquaporins in the kidneys of agnathans
and elasmobranchs would allow comparative hypotheses to be tested regarding the role and evolution of aquaporins in fish kidneys.
The Early Devonian armoured agnathans
of Podolia, Ukraine.
The list of agnathans
of the Himmiste Beds in the Himmiste-Kuigu quarry contains thelodonts Thelodus laevis (Pander), T.
Origins of the descending spinal projections in petromyzontid and myxinoid agnathans
According to him, no real sensory line canal or groove was visible on the outer surface, but the row of foramina might have affected the conditions of a pit-line and could be the homologue of the ventral longitudinal sensory line of some agnathans
(Janvier 1978, p.
Some marl levels downstream along the Lemovzha River contain well-preserved remains of agnathans
and fishes (Ivanov & Lebedev 2011; Skutschas et al.
Because these sheaths are absent in agnathans
(Bullock et al.
The taxonomy and distribution of agnathans
and fishes in southern Britain have been investigated, the regional vertebrate zonal scheme has been updated and characteristic vertebrate assemblages have been correlated with the conodont zonation (Miller & Marss 1999; Turner 2000; Marss & Miller 2004).
Because the phylogeny, as well as the fertilization, of living agnathans
(hagfish and lampreys) has attracted much attention from biologists (Brodal and Fange, 1963; Hardisty, 1979), we compared these sperm to those of other chordates.
1931), produced additional specimens, exhausting the quarry; in recent decades, no articulated agnathans
have been found apart from a few shields of Tremataspis mammillata Patten and Dartmuthia gemmifera Patten.
The fossil fishes that have so far been used for distinguishing zones are agnathans
, placoderms and acanthodians (e.
Such a very fine pattern has been observed on the scales of both agnathans
and gnathostome fishes (Marss 2006) in the Palaeozoic, and some details of the external surface of scales and tubercles have been illustrated in publications on histology (e.
Such a very fine pattern has been observed on agnathans
(Gross 1967; Blieck 1982; Marss 1986; Long et al.
During the last few decades the palaeontological studies in Estonia have been dealing with corals, stromatoporoids, brachiopods, trilobites, ostracods, conodonts, chitinozoans, scolecodonts, acritarchs, agnathans
, early fishes and tetrapods, and various other groups of organisms.
The nektic, nektobenthic and planktic communities (fishes, agnathans
, conodonts, graptolites, chitinozoans) of the East Baltic Silurian.