View source for Epilobium sect. Xerolobium

{{Treatment/ID
|accepted_name=Epilobium sect. Xerolobium
|accepted_authority=P. H. Raven
|publications={{Treatment/Publication
|title=Ann. Missouri Bot. Gard.
|place=63: 334. 1977
|year=1977
}}
|basionyms=
|synonyms=
|hierarchy=Onagraceae;Onagraceae subfam. Onagroideae;Onagraceae tribe Epilobieae;Epilobium;Epilobium sect. Xerolobium
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Onagraceae]]</div><div class="higher-taxon"><small>subfamily</small>[[Onagraceae subfam. Onagroideae]]</div><div class="higher-taxon"><small>tribe</small>[[Onagraceae tribe Epilobieae]]</div><div class="higher-taxon"><small>genus</small>[[Epilobium]]</div><div class="higher-taxon"><small>section</small>[[Epilobium sect. Xerolobium]]</div></div>
|volume=Volume 10
|mention_page=
|treatment_page=
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--><span class="statement" id="st-d0_s0" data-properties="herb duration"><b>Herbs </b>annual, with taproot.</span> <span class="statement" id="st-d0_s1" data-properties=""><b>Stems:</b> epidermis peeling proximally.</span> <span class="statement" id="st-d0_s2" data-properties="leaf arrangement;leaf duration;leaf arrangement;leaf architecture or arrangement"><b>Leaves </b>opposite and early deciduous in proximalmost pairs, alternate and sometimes fasciculate distally.</span> <span class="statement" id="st-d0_s3" data-properties="flower architecture"><b>Flowers </b>actinomorphic;</span> <span class="statement" id="st-d0_s4" data-properties="base architecture">floral-tube without bulbous base or scales inside;</span> <span class="statement" id="st-d0_s5" data-properties="petal coloration;petal coloration;petal coloration;petal coloration">petals rose-purple to pink or white;</span> <span class="statement" id="st-d0_s6" data-properties="tetrad arrangement">pollen usually shed singly, rarely in tetrads;</span> <span class="statement" id="st-d0_s7" data-properties="stigma architecture or shape;stigma shape;stigma shape;stigma shape">stigma entire and clavate to deeply 4-lobed.</span> <span class="statement" id="st-d0_s8" data-properties="capsule shape;capsule shape;capsule architecture or dehiscence;central column duration"><b>Capsules </b>narrowly cylindrical or fusiform, splitting to base, central column persistent, pedicellate.</span> <span class="statement" id="st-d0_s9" data-properties="seed quantity;seed shape;seed shape;seed shape;seed size;row quantity;coma presence"><b>Seeds </b>numerous, in 1 row per locule, obovoid to broadly obovoid, prominently constricted near micropylar end, coma present.</span><!--

-->{{Treatment/Body
|distribution=w North America;in sw South America;Europe
|discussion=<p>Species 1.</p><!--
--><p>Section Xerolobium consists only of the annual species Epilobium brachycarpum, with n = 12, a unique chromosome number apparently derived by aneuploidy from the tribal base number of × = 18. It differs from the other annual taxa in sects. Epilobiopsis (n = 15) and Pachydium (n = 9, 10, 19) not only in chromosome number, but also by flowering in summer, whereas the other taxa are primarily spring-flowering.</p><!--
--><p>Section Xerolobium shares with sects. Cordylophorum and Zauschneria the apomorphic features of the so-called incised compound pollen viscin threads (J. J. Skvarla et al. 1978; also found in sect. Pachydium and in Epilobium minutum of sect. Crossostigma) and in having seeds prominently constricted at the micropylar end (S. R. Seavey et al. 1977; also found in E. rigidum of sect. Macrocarpa and E. foliosum of sect. Crossostigma). In addition to its autapomorphic chromosome number, E. brachycarpum is marked as phylogenetically distinct by virtue of shedding its pollen in monads (Skvarla et al. 1975). All but a few exceptionally large-flowered populations in a small area of northern California (sometimes designated as E. jucundum) have monads, a feature otherwise found in Epilobieae only in Chamaenerion. The feature of shedding pollen as monads was clearly derived independently within E. brachycarpum.</p>
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|references=
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-->{{#Taxon:
name=Epilobium sect. Xerolobium
|authority=P. H. Raven
|rank=section
|parent rank=genus
|synonyms=
|basionyms=
|family=Onagraceae
|distribution=w North America;in sw South America;Europe
|reference=None
|publication title=Ann. Missouri Bot. Gard.
|publication year=1977
|special status=
|source xml=
|subfamily=Onagraceae subfam. Onagroideae
|tribe=Onagraceae tribe Epilobieae
|genus=Epilobium
|section=Epilobium sect. Xerolobium
|base architecture=bulbous
|capsule architecture or dehiscence=splitting
|capsule shape=fusiform;cylindrical
|central column duration=persistent
|coma presence=absent
|flower architecture=actinomorphic
|herb duration=annual
|leaf architecture or arrangement=fasciculate
|leaf arrangement=alternate;opposite
|leaf duration=deciduous
|petal coloration=rose-purple;pink or white
|row quantity=1
|seed quantity=numerous
|seed shape=obovoid;broadly obovoid
|seed size=constricted
|stigma architecture or shape=entire
|stigma shape=clavate;deeply 4-lobed
|tetrad arrangement=singly
}}<!--

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