Abstract:
:The silk production systems of several specimens representing at least three species of the mygalomorph genus Euagrus were examined by dissection and by a variety of absorption and fluorescent histochemical techniques. The intrageneric variation is primarily restricted to gland number, with larger numbers of glands in the larger-bodied species. The silk glands are arranged in four groups each serving one of four spinnerets. Spigot morphology is uniform, consisting of a long, slender shaft of slightly variable length emerging from an enlarged sac-shaped base. Only one gland type is identified histochemically, although a considerable range in size and shape is observed. Each gland has three secretory zones, a distal one that produces a largely hydrophobic protein core and medial and proximal zones that produce distinct charged protein coatings. Amino acid analysis of the silk indicates a composition very similar to the frame threads and draglines of araneomorph spiders. The high percentage of short side-chain amino acids implies a polymer structure able to support the suspended entrapment web found in Euagrus and its relatives (but which is rare in most other nonaraneomorph families). Dry silk examined under high magnification appears smooth and homogenous. The fact that in the web larger threads appear to fibrillate suggests that Euagrus silk is polyfilamentous.
journal_name
J Morpholjournal_title
Journal of morphologyauthors
Palmer JMdoi
10.1002/jmor.1051860205subject
Has Abstractpub_date
1985-11-01 00:00:00pages
195-207issue
2eissn
0362-2525issn
1097-4687journal_volume
186pub_type
杂志文章abstract::Astroblepidae or "climbing catfishes" encompass a single genus of species living in high altitude rivers in the Andes of South America. They are characterized by a specialized head morphology closely resembling their better known, widely radiated sister family Loricariidae, or armored suckermouth catfishes. Existent d...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20169
更新日期:2013-10-01 00:00:00
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journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051900305
更新日期:1986-12-01 00:00:00
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journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/(SICI)1097-4687(199607)229:1<1::AID-JMOR1>
更新日期:1996-07-01 00:00:00
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journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051350309
更新日期:1971-11-01 00:00:00
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journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052070109
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journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10502
更新日期:2007-02-01 00:00:00
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journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051830308
更新日期:1985-03-01 00:00:00
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journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052040103
更新日期:1990-04-01 00:00:00
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journal_title:Journal of morphology
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更新日期:2008-07-01 00:00:00
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journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10787
更新日期:2010-02-01 00:00:00
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journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051540204
更新日期:1977-11-01 00:00:00
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journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052170102
更新日期:1993-07-01 00:00:00
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journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/(SICI)1097-4687(199612)230:3<265::AID-JMOR
更新日期:1996-12-01 00:00:00
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journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10186
更新日期:2004-03-01 00:00:00
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journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051760306
更新日期:1983-06-01 00:00:00
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journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.21138
更新日期:2020-06-01 00:00:00
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journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051880104
更新日期:1986-04-01 00:00:00
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journal_title:Journal of morphology
pub_type: 杂志文章
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更新日期:1995-02-01 00:00:00
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journal_title:Journal of morphology
pub_type: 杂志文章
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pub_type: 杂志文章
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journal_title:Journal of morphology
pub_type: 杂志文章
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更新日期:2009-05-01 00:00:00
abstract::The functioning of the vertebrate eye depends on its absolute size, which is presumably adapted to specific needs. Eye size variation in lidless and spectacled colubrid snakes was investigated, including 839 specimens belonging to 49 genera, 66 species and subspecies. Variations of adult eye diameters (EDs) in both ab...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20028
更新日期:2012-08-01 00:00:00
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journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/(SICI)1097-4687(199604)228:1<1::AID-JMOR1>
更新日期:1996-04-01 00:00:00
abstract::The Puerto Rican tree frog, Eleutherodactylus coqui, has internal fertilization and direct development on land. In light of these reproductive adaptations, the events of fertilization and early development were studied. Cytological examination of just-fertilized eggs showed that sperm entry is restricted to about 10% ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051930208
更新日期:1987-08-01 00:00:00
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journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10135
更新日期:2003-12-01 00:00:00
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journal_title:Journal of morphology
pub_type: 杂志文章
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更新日期:1979-08-01 00:00:00
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journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/(SICI)1097-4687(199807)237:1<33::AID-JMOR3
更新日期:1998-07-01 00:00:00
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journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051980110
更新日期:1988-10-01 00:00:00
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journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051540106
更新日期:1977-10-01 00:00:00