{"id":1407,"date":"2016-01-22T21:18:56","date_gmt":"2016-01-22T21:18:56","guid":{"rendered":"http:\/\/blogs.uakron.edu\/weeks\/?page_id=1407"},"modified":"2025-09-09T14:36:58","modified_gmt":"2025-09-09T14:36:58","slug":"eulimnadia-texana-images","status":"publish","type":"page","link":"https:\/\/blogs.uakron.edu\/weeks\/branchiopod-crustacean-info\/eulimnadia-texana-images\/","title":{"rendered":"Eulimnadia texana Images"},"content":{"rendered":"<figure id=\"attachment_1411\" aria-describedby=\"caption-attachment-1411\" style=\"width: 144px\" class=\"wp-caption alignleft\"><a href=\"http:\/\/blogs.uakron.edu\/weeks\/wp-content\/uploads\/sites\/1287\/2016\/01\/etherm2.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-1411\" src=\"http:\/\/blogs.uakron.edu\/weeks\/wp-content\/uploads\/sites\/1287\/2016\/01\/etherm2.jpg\" alt=\"Fig. 1. Eulimnadia texana hermaphrodite\" width=\"144\" height=\"115\" \/><\/a><figcaption id=\"caption-attachment-1411\" class=\"wp-caption-text\">Fig. 1. <em>Eulimnadia texana<\/em> hermaphrodite<\/figcaption><\/figure>\n<p><i>Eulimnadia<\/i> <i>texana<\/i> are &#8220;clam shrimp&#8221; that inhabit temporary playas, ditches, and many other ephemeral freshwater habitats throughout the southern United States, west of the Mississippi River, and into northern Mexico (Sassaman, 1989). Hermaphrodites (Fig. 1) produce desiccation-resistant cysts (Fig. 2) which they carry in a brood chamber in the crease of their folded carapace (Fig. 3).<\/p>\n<hr \/>\n<div id='gallery-1' class='gallery galleryid-1407 gallery-columns-2 gallery-size-thumbnail'><figure class='gallery-item'>\n\t\t\t<div class='gallery-icon landscape'>\n\t\t\t\t<a href='https:\/\/blogs.uakron.edu\/weeks\/branchiopod-crustacean-info\/eulimnadia-texana-images\/eggs1\/'><img loading=\"lazy\" decoding=\"async\" width=\"150\" height=\"120\" src=\"https:\/\/blogs.uakron.edu\/weeks\/wp-content\/uploads\/sites\/1287\/2016\/01\/EGGS1-e1453496479953.jpg?w=150&amp;h=120&amp;crop=1\" class=\"attachment-thumbnail size-thumbnail\" alt=\"\" aria-describedby=\"gallery-1-1415\" \/><\/a>\n\t\t\t<\/div>\n\t\t\t\t<figcaption class='wp-caption-text gallery-caption' id='gallery-1-1415'>\n\t\t\t\tFig. 2. E. texana eggs (cysts).\n\t\t\t\t<\/figcaption><\/figure><figure class='gallery-item'>\n\t\t\t<div class='gallery-icon landscape'>\n\t\t\t\t<a href='https:\/\/blogs.uakron.edu\/weeks\/branchiopod-crustacean-info\/eulimnadia-texana-images\/eggsbrd2\/'><img loading=\"lazy\" decoding=\"async\" width=\"150\" height=\"120\" src=\"https:\/\/blogs.uakron.edu\/weeks\/wp-content\/uploads\/sites\/1287\/2016\/01\/eggsbrd2.jpg?w=150&amp;h=120&amp;crop=1\" class=\"attachment-thumbnail size-thumbnail\" alt=\"\" aria-describedby=\"gallery-1-1419\" \/><\/a>\n\t\t\t<\/div>\n\t\t\t\t<figcaption class='wp-caption-text gallery-caption' id='gallery-1-1419'>\n\t\t\t\tFig. 3. Close-up of egg brood chamber of hermaphrodites \n\t\t\t\t<\/figcaption><\/figure>\n\t\t<\/div>\n\n<p>The hermaphrodites bury the eggs within the top several millimeters of the soil. These cysts hatch rapidly following hydration under spring and summer conditions (at water temperatures above 18<span style=\"font-family: Symbol\">\u00b0<\/span> C), releasing a nauplius larva (Fig. 4).<\/p>\n<hr \/>\n<figure id=\"attachment_1335\" aria-describedby=\"caption-attachment-1335\" style=\"width: 134px\" class=\"wp-caption alignright\"><a href=\"http:\/\/blogs.uakron.edu\/weeks\/wp-content\/uploads\/sites\/1287\/2016\/01\/NAUPLII21.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-1335\" src=\"http:\/\/blogs.uakron.edu\/weeks\/wp-content\/uploads\/sites\/1287\/2016\/01\/NAUPLII21.jpg\" alt=\"Fig. 4. E. texana nauplius larva\" width=\"134\" height=\"121\" \/><\/a><figcaption id=\"caption-attachment-1335\" class=\"wp-caption-text\">Fig. 4. E. texana nauplius larva<\/figcaption><\/figure>\n<p>Larval and juvenile growth is extraordinarily rapid. Shrimp reach reproductive size in 4 &#8211; 7 days in the laboratory at 27 &#8211; 30<span style=\"font-family: Symbol\">\u00b0<\/span> C, and in as little as 4 &#8211; 6 days in the field. The hermaphrodites produce thousands of eggs in their lifetime, generating clutches ranging between 100-300 eggs, one to two times a day. Hermaphrodites often dig a shallow burrow into which eggs are released. Clutch size increases significantly with carapace length, but no difference in clutch size was detected between selfed and outcrossed clutches in the laboratory.<\/p>\n<hr \/>\n<figure id=\"attachment_1459\" aria-describedby=\"caption-attachment-1459\" style=\"width: 160px\" class=\"wp-caption alignleft\"><a href=\"http:\/\/blogs.uakron.edu\/weeks\/wp-content\/uploads\/sites\/1287\/2016\/01\/etmale2.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-1459\" src=\"http:\/\/blogs.uakron.edu\/weeks\/wp-content\/uploads\/sites\/1287\/2016\/01\/etmale2.jpg\" alt=\"Fig. 5. Eulimnadia texana male\" width=\"160\" height=\"120\" \/><\/a><figcaption id=\"caption-attachment-1459\" class=\"wp-caption-text\">Fig. 5. <em>Eulimnadia texana<\/em> male<\/figcaption><\/figure>\n<p>Sexual dimorphism is pronounced. The thoracic appendages of hermaphrodites are unmodified (Fig. 1), but the first two pairs of thoracic appendages in males undergo differentiation into claw-like claspers (Fig. 5) which are used to hold on to the margins of a hermaphrodite&#8217;s carapace during mating (Fig. 6).<\/p>\n<hr \/>\n<p><i>Eulimnadia<\/i> <i>texana<\/i> is omnivorous, able to filter feed as well as forage along pond bottoms.<\/p>\n<figure id=\"attachment_1499\" aria-describedby=\"caption-attachment-1499\" style=\"width: 110px\" class=\"wp-caption alignright\"><a href=\"http:\/\/blogs.uakron.edu\/weeks\/wp-content\/uploads\/sites\/1287\/2016\/01\/etmate2.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-1499\" src=\"http:\/\/blogs.uakron.edu\/weeks\/wp-content\/uploads\/sites\/1287\/2016\/01\/etmate2.jpg\" alt=\"Fig. 6. Mating pair (male above, hermaphrodite below)\" width=\"110\" height=\"230\" \/><\/a><figcaption id=\"caption-attachment-1499\" class=\"wp-caption-text\">Fig. 6. Mating pair (male above, hermaphrodite below)<\/figcaption><\/figure>\n<p>Natural populations of <i>Eulimnadia<\/i> are typically hermaphrodite-biased, with some populations completely lacking males. <i>Eulimnadia<\/i> <i>texana<\/i> populations range from 0 &#8211; 40 percent males, and inbreeding is positively correlated with hermaphrodite-biased sex ratios. Average inbreeding coefficients calculated from six natural populations ranged between 0.20 and 1.0, with an average of 0.49.<\/p>\n<p>Histological examinations of the gonads of <i>E. texana<\/i> proves the assumption that the populations are composed of males and hermaphrodites. Hermaphrodites have both testicular and ovarian tissue, while males have only testicular tissue (Fig. 7).<\/p>\n<hr \/>\n<figure id=\"attachment_1503\" aria-describedby=\"caption-attachment-1503\" style=\"width: 196px\" class=\"wp-caption alignleft\"><a href=\"http:\/\/blogs.uakron.edu\/weeks\/wp-content\/uploads\/sites\/1287\/2016\/01\/gonads2.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-1503\" src=\"http:\/\/blogs.uakron.edu\/weeks\/wp-content\/uploads\/sites\/1287\/2016\/01\/gonads2.jpg\" alt=\"Fig. 7. Cross section of gonads of E. texana (photo courtesy of Naida Zucker, New Mexico State University)\" width=\"196\" height=\"160\" \/><\/a><figcaption id=\"caption-attachment-1503\" class=\"wp-caption-text\">Fig. 7. Cross section of gonads of E. texana (photo courtesy of Naida Zucker, New Mexico State University)<\/figcaption><\/figure>\n<p>Current histological examinations are aimed at determining when and where fertilization occurs. Developing ova in the ovotestes show no signs of multiple nuclei indicative of fertilization (Fig. 8).<\/p>\n<hr \/>\n<figure id=\"attachment_1507\" aria-describedby=\"caption-attachment-1507\" style=\"width: 300px\" class=\"wp-caption alignright\"><a href=\"http:\/\/blogs.uakron.edu\/weeks\/wp-content\/uploads\/sites\/1287\/2016\/01\/unferteg.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"size-medium wp-image-1507\" src=\"http:\/\/blogs.uakron.edu\/weeks\/wp-content\/uploads\/sites\/1287\/2016\/01\/unferteg-300x217.jpg\" alt=\"Fig. 8. Developing ova in the ovotestes.\" width=\"300\" height=\"217\" \/><\/a><figcaption id=\"caption-attachment-1507\" class=\"wp-caption-text\">Fig. 8. Developing ova in the ovotestes.<\/figcaption><\/figure>\n<p>Eggs in the brood chamber show signs of developing embryos (Fig. 9), suggesting that either\u00a0fertilization is internal but initial cell division does not occur until the eggs are in the brood chamber, or that eggs are actually fertilized externally. Future work is concentrating on delineating these two alternatives.<\/p>\n<figure id=\"attachment_1511\" aria-describedby=\"caption-attachment-1511\" style=\"width: 300px\" class=\"wp-caption alignleft\"><a href=\"http:\/\/blogs.uakron.edu\/weeks\/wp-content\/uploads\/sites\/1287\/2016\/01\/eggsec2.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"size-medium wp-image-1511\" src=\"http:\/\/blogs.uakron.edu\/weeks\/wp-content\/uploads\/sites\/1287\/2016\/01\/eggsec2-300x290.jpg\" alt=\"Fig. 9. Fertilized egg from brood chamber. Crescent shaped body is developing embryo.\" width=\"300\" height=\"290\" \/><\/a><figcaption id=\"caption-attachment-1511\" class=\"wp-caption-text\">Fig. 9. Fertilized egg from brood chamber. Crescent shaped body is developing embryo.<\/figcaption><\/figure>\n<hr \/>\n<p>For further information on the sex determining mechanism of <i>E. texana<\/i>, check out the article in <a href=\"http:\/\/blogs.uakron.edu\/weeks\/sample-page\/published-research\/american-naturalist-1-1993\/\"><span style=\"color: #0000ff\">The<\/span> <span style=\"color: #0000ff\">American Naturalist<\/span><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Eulimnadia texana are &#8220;clam shrimp&#8221; that inhabit temporary playas, ditches, and many other ephemeral freshwater habitats throughout the southern United States, west of the Mississippi River, and into northern Mexico (Sassaman, 1989). Hermaphrodites (Fig. 1) produce desiccation-resistant cysts (Fig. 2) which they carry in a brood chamber in the crease of their folded carapace (Fig. [&hellip;]<\/p>\n","protected":false},"author":2555,"featured_media":0,"parent":1319,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"class_list":["post-1407","page","type-page","status-publish","hentry"],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/blogs.uakron.edu\/weeks\/wp-json\/wp\/v2\/pages\/1407","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.uakron.edu\/weeks\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/blogs.uakron.edu\/weeks\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.uakron.edu\/weeks\/wp-json\/wp\/v2\/users\/2555"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.uakron.edu\/weeks\/wp-json\/wp\/v2\/comments?post=1407"}],"version-history":[{"count":27,"href":"https:\/\/blogs.uakron.edu\/weeks\/wp-json\/wp\/v2\/pages\/1407\/revisions"}],"predecessor-version":[{"id":8082,"href":"https:\/\/blogs.uakron.edu\/weeks\/wp-json\/wp\/v2\/pages\/1407\/revisions\/8082"}],"up":[{"embeddable":true,"href":"https:\/\/blogs.uakron.edu\/weeks\/wp-json\/wp\/v2\/pages\/1319"}],"wp:attachment":[{"href":"https:\/\/blogs.uakron.edu\/weeks\/wp-json\/wp\/v2\/media?parent=1407"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}