CARADOC BRACHIOPODS FROM THE SHAN STATES 



13 



Table 1 Affinity indices between eight Caradoc brachiopod faunas. BUR, the present fauna; SCH, Guizhou, South China; NCH, Shaanxi, North China; 

 KAZ. Chingiz, Kazakhstan; ALT. Gorny Altai, Russia; WAL, Bala, Wales; NSW, New South Wales, Australia; BCC, British Columbia, Canada (for 

 stratigraphy and references see text). Three numbers are shown for each relationship following the different formulae discussed by Rong et al. (1995) in 

 the lower left part of the diagram and their averages in the upper diagonal. 





BUR 



SCH 



NCH 



KAZ 



ALT 



WAL 



NSW 



BCC 



BUR 



1 



0.3373 



0.2557 



0.1063 



0.1135 



0.2752 



0.0388 



0.0480 



SCH 



0.3708 

 0.3600 

 0.2810 



1 



0.1842 



0.0222 







0.1726 



0.0580 



0.0165 



NCH 



0.2884 

 0.2800 

 0.1986 



0.2226 

 0.2222 

 0.1079 



1 



0.0800 



0.1039 



0.3156 



0.0997 



0.1138 



KAZ 



0.1391 

 0.1304 

 0.0493 



0.0626 

 0.0625 

 -0.0586 



0.1185 

 0.1176 

 0.0038 



1 



0.0178 



0.0567 



0.0169 







ALT 



0.1437 

 0.1429 

 0.0539 







0.1376 

 0.1364 

 0.0376 



0.0516 

 0.0500 

 -0.0484 



1 



0.1064 



0.1218 



0.1410 



WAL 



0.3036 

 0.3030 

 0.2191 



0.2050 

 0.1923 

 0.1205 



0.3490 

 0.3333 

 0.2645 



0.0873 

 0.0800 

 0.0028 



0.1352 

 0.1333 

 0.0507 



1 



0.0691 



0.0448 



NSW 



0.0691 

 0.0678 

 -0.0207 



0.0907 

 0.0889 

 -0.0055 



0.1325 

 0.1304 

 0.0362 



0.0497 

 0.0476 

 -0.0465 



0.1540 

 0.1538 

 0.0577 



0.0976 

 0.0968 

 0.0131 



1 



0.0517 



BCC 



0.0784 

 0.0769 

 -0.0114 



0.0529 

 0.0526 

 -0.0562 



0.1502 

 0.1500 

 0.0411 







0.1746 

 0.1739 

 0.0746 



0.0738 

 0.0714 

 -0.0107 



0.0840 

 0.0833 

 -0.0122 



1 



was in poor faunal contact with South China and Sibumasu in the 

 Late Ordovician, even though they were both parts of Gondwana. 

 The Caradoc faunas from Kazakhstan and Altai are greatly 

 different from the Naungkangyi fauna; a result which is in 

 contrast with the findings of Zhan & Cocks (1998), which 

 indicated that those two terranes were closely related faunally to 

 the South China terrane in mid Ashgtll time. 

 5 . The comparatively deeper- water Bimuria fauna of North America 

 described by Jin & Norford (1996) from the Advance Formation 

 in the northern Rocky Mountains, British Columbia, has extremely 

 low similarities with any other contemporary faunas compared 

 here, which indicates that all the other seven sites were far away 

 from Laurentia in Caradoc times. 



Thus this brachiopod faunal analysis supports Fortey & Cocks' 

 (1998) conclusions that during the Late Ordovician the Sibumasu 

 terrane was closely related to South and North China, and that 

 Sibumasu was closer to South China, in contrast with the latter's 

 closeness to North China in the Early Ordovician. 



SYSTEMATIC PALAEONTOLOGY 



The figured and cited specimens are deposited in the Natural History 

 Museum, London (BB and BC) and the Sedgwick Museum, Cam- 

 bridge (SMA). Dimensions (in mm) are L = length. W = width. L, = 



length of cardinalia or ventral muscle field, L, = distance of the 

 anterior end of dorsal muscle field away from the umbo, W : = width 

 of cardinalia or ventral muscle field, W, = width of dorsal muscle 

 field, N = number of ribs, <^ = angle between the socket ridges or 

 brachiophores. 



Superfamily LINGULOIDEA Menke, 

 Family LINGULIDAE Menke, 182 



828 



Genus PALAEOGLOSSA Cockerell, 1911 



Palaeoglossa? sp. 



1915 Lingula cf. attenuata Sowerby; Reed: 8, pi. 2, fig. 5. 



Discussion. Lingula cf. attenuata was described by Reed 

 (1915) from the Upper Naungkangyi Group (late Caradoc) of 

 Man-ngai, Northern Shan States, and is tentatively attributed to 

 the genus Palaeoglossa here, since Sowerby's attenuata is now 

 the type species of that genus (Cocks 1978). However, no original 

 material from the Burmese Ordovician is available to us and we 

 are hesitant to identify the species. In addition, Reed (1906: 49, 

 pi. 4, fig. 1) also listed Lingula cf. quadrata Eichwald from the 

 Naungkangyi Group of Palin. Northern Shan States. This latter 

 might be reassigned to the oboloid Lingulella using the differ- 

 ences between Lingula and Lingulella featured in Williams el al. 

 (1965) and Holmer ( 1989). 



