Neckera andina

Neckera andina View in CoL ( Fig. 5A–D)

This species has abundant paraphyllia, and their arrangement in many parts of stem is irregular. Paraphyllia are more numerous closer to branch primordia and some clusters of them occur in the place where the bud typically develops but is not always apparent. The pellucid area around branch primordia is inapparent. The transitions between branch leaves on the base of branch, compound proximal branch leaves and paraphyllia are gradual, thus in many cases separation of these structures is arbitrary. This can be demonstrated by a series shown in Figs. 5A–D. In buds with proximal branch leaves broadly ovate, the paraphyllia are often fewer and their arrangement more or less agrees with the usual phyllotaxis of proximal branch leaves ( Fig. 5A). The bud with the narrower proximal branch leaves is shown in Fig. 5B. The proximal branch leaves have an apparent phyllotaxis and they are situated somewhat apart from the ‘inner’ part of the bud. A moderately abundant subfilamentous paraphyllia are situated mostly behind the large lanceolate proximal branch leaves ( Fig. 5B). Further variant looks as a rather large cluster of thin filamentous to narrowly lanceolate paraphyllia, with broadest of them being in central position ( Fig. 5C); sometimes a raised structure, apparently equivalent of the inner part of bud, is discernable between these broadest foliose structures, but sometimes it is hard to say if it exists. The phyllotaxis of such broadest foliose structures is usually inapparent, thus their identity and terminology are losing a rational explanation: such cases represent simply an intermediates between proximal branch leaves and paraphyllia. Finally, the area between corners of the leaves N+1 and N+2 possesses a number of filamentous structures ( Fig. 5D). Sometimes some of them in the centre are slightly larger, while often they are all subidentical. A characteristic feature of such assemblages is that some paraphyllia are pointed upwards and some downwards. The same pattern is characteristic also for Neckera californica Hook. & Arn. (not shown here, but illustrated by Ignatov & Hedenäs, 2007), and sometimes for another genus of the Neckeraceae , Leptodon smithii (Dicks. ex Hedw.) F. Weber & D. Mohr ( Fig. 6). Also worthy is a comparison with the case shown for Exsertotheca in Fig. 3A, where short filamentous structures appear in between corners of the leaves N+1 and N+2 (where N is mother leaf of the area, cf. Fig. 4B).