Pre-emergence growth and development in the arctic midge Trichotanypus alaskensis Brundin
Developing at low mean temperatures, arctic chironomids often have prolonged larval growth yet adult emergence is typically a brief and highly synchronous event. How does a midge population achieve synchronous emergence? Under the Absolute Spring Species Hypothesis (AbSS), adult eclosion by early-em...
| Main Authors: | , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
PAGEPress Publications
2018-08-01
|
| Series: | Journal of Limnology |
| Subjects: | |
| Online Access: | https://www.jlimnol.it/index.php/jlimnol/article/view/1836 |
| _version_ | 1811318555907457024 |
|---|---|
| author | Malcolm G. Butler Shane D. Braegelman |
| author_facet | Malcolm G. Butler Shane D. Braegelman |
| author_sort | Malcolm G. Butler |
| collection | DOAJ |
| description | Developing at low mean temperatures, arctic chironomids often have prolonged larval growth yet adult emergence is typically a brief and highly synchronous event. How does a midge population achieve synchronous emergence? Under the Absolute Spring Species Hypothesis (AbSS), adult eclosion by early-emerging species may be synchronized by overwintering as fully mature larvae. Such prepupal larvae would neither feed nor grow after spring thaw, only pupate and emerge. The podonomine Trichotanypus alaskensis Brundin is an abundant midge in tundra ponds on Alaska’s Arctic Coastal Plain, and one of the earliest-emerging species in this chironomid-dominated insect community. T. alaskensis is univoltine in these arctic ponds, with most emergence from any one pond occurring within less than a one-week span during late June, typically about three weeks after pond thaw. We evaluated T. alaskensis for conformity to the AbSS model by documenting the overwintering state of this species in a tundra pond near Barrow, Alaska, then monitoring larval growth and development of the population from spring thaw to pupation. Most T. alaskensis were immature instar IV larvae when collected in late September of both 2010 and 2011, with 10-30% still in late instar III. Immediately after pond thaw in 2011, all collected larvae had imaginal disc primordia showing early stages of instar IV development. Within the first two weeks following pond thaw, most larvae had doubled their dry mass and developed into mature (prepupal) final-instar larvae. Highly synchronized emergence by T. alaskensis is not a consequence of a population overwintering as fully-mature larvae, as per the Absolute Spring Species Hypothesis. Rather, larvae in a given tundra pond appear to develop synchronously throughout the life cycle, including a period of substantial growth and rapid prepupal development between spring thaw and early-summer emergence. |
| first_indexed | 2024-04-13T12:27:52Z |
| format | Article |
| id | doaj.art-4cd3d1862e6d400ab41f7f2916fd2151 |
| institution | Directory Open Access Journal |
| issn | 1129-5767 1723-8633 |
| language | English |
| last_indexed | 2024-04-13T12:27:52Z |
| publishDate | 2018-08-01 |
| publisher | PAGEPress Publications |
| record_format | Article |
| series | Journal of Limnology |
| spelling | doaj.art-4cd3d1862e6d400ab41f7f2916fd21512022-12-22T02:46:58ZengPAGEPress PublicationsJournal of Limnology1129-57671723-86332018-08-0110.4081/jlimnol.2018.1836Pre-emergence growth and development in the arctic midge Trichotanypus alaskensis BrundinMalcolm G. Butler0Shane D. Braegelman1North Dakota State UniversityNorth Dakota State UniversityDeveloping at low mean temperatures, arctic chironomids often have prolonged larval growth yet adult emergence is typically a brief and highly synchronous event. How does a midge population achieve synchronous emergence? Under the Absolute Spring Species Hypothesis (AbSS), adult eclosion by early-emerging species may be synchronized by overwintering as fully mature larvae. Such prepupal larvae would neither feed nor grow after spring thaw, only pupate and emerge. The podonomine Trichotanypus alaskensis Brundin is an abundant midge in tundra ponds on Alaska’s Arctic Coastal Plain, and one of the earliest-emerging species in this chironomid-dominated insect community. T. alaskensis is univoltine in these arctic ponds, with most emergence from any one pond occurring within less than a one-week span during late June, typically about three weeks after pond thaw. We evaluated T. alaskensis for conformity to the AbSS model by documenting the overwintering state of this species in a tundra pond near Barrow, Alaska, then monitoring larval growth and development of the population from spring thaw to pupation. Most T. alaskensis were immature instar IV larvae when collected in late September of both 2010 and 2011, with 10-30% still in late instar III. Immediately after pond thaw in 2011, all collected larvae had imaginal disc primordia showing early stages of instar IV development. Within the first two weeks following pond thaw, most larvae had doubled their dry mass and developed into mature (prepupal) final-instar larvae. Highly synchronized emergence by T. alaskensis is not a consequence of a population overwintering as fully-mature larvae, as per the Absolute Spring Species Hypothesis. Rather, larvae in a given tundra pond appear to develop synchronously throughout the life cycle, including a period of substantial growth and rapid prepupal development between spring thaw and early-summer emergence.https://www.jlimnol.it/index.php/jlimnol/article/view/1836PodonominaeChironomidaeArcticprepupal developmentemergence synchronyAbsolute Spring Species Hypothesis. |
| spellingShingle | Malcolm G. Butler Shane D. Braegelman Pre-emergence growth and development in the arctic midge Trichotanypus alaskensis Brundin Journal of Limnology Podonominae Chironomidae Arctic prepupal development emergence synchrony Absolute Spring Species Hypothesis. |
| title | Pre-emergence growth and development in the arctic midge Trichotanypus alaskensis Brundin |
| title_full | Pre-emergence growth and development in the arctic midge Trichotanypus alaskensis Brundin |
| title_fullStr | Pre-emergence growth and development in the arctic midge Trichotanypus alaskensis Brundin |
| title_full_unstemmed | Pre-emergence growth and development in the arctic midge Trichotanypus alaskensis Brundin |
| title_short | Pre-emergence growth and development in the arctic midge Trichotanypus alaskensis Brundin |
| title_sort | pre emergence growth and development in the arctic midge trichotanypus alaskensis brundin |
| topic | Podonominae Chironomidae Arctic prepupal development emergence synchrony Absolute Spring Species Hypothesis. |
| url | https://www.jlimnol.it/index.php/jlimnol/article/view/1836 |
| work_keys_str_mv | AT malcolmgbutler preemergencegrowthanddevelopmentinthearcticmidgetrichotanypusalaskensisbrundin AT shanedbraegelman preemergencegrowthanddevelopmentinthearcticmidgetrichotanypusalaskensisbrundin |