A new species of Heterotrissocladius Spaerck, 1923 (Diptera: Chironomidae: Orthocladiinae) from Georgia, USA

Heterotrissocladius spiesi sp. n. is described from headwaters of two small Georgia streams (USA), below the Fall Line in the Coastal Plain Physiologic Province, Atlantic Slope drainage. One stream is near the coast (Lower Coastal Plain, Big Creek) and characterized as a 'blackwater' strea...

Full description

Saved in:
Bibliographic Details
Published in:Journal of limnology 2018-01, Vol.77 (1), p.59-64
Main Authors: Caldwell, B A, Jacobsen, R E
Format: Article
Language:English
Subjects:
Animal morphology
Aquatic insects
Coastal plains
Entomology
Freshwater
Geographical distribution
Headwaters
Heterotrissocladius boltoni
Heterotrissocladius marcidus
Heterotrissocladius spiesi
Inland water environment
Males
New species
New taxa
Pupae
Setae
Skin
Tannins
Taxonomy
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Heterotrissocladius spiesi sp. n. is described from headwaters of two small Georgia streams (USA), below the Fall Line in the Coastal Plain Physiologic Province, Atlantic Slope drainage. One stream is near the coast (Lower Coastal Plain, Big Creek) and characterized as a 'blackwater' stream due to high tannin concentrations. The other stream is inland (Upper Coastal Plain), clear and not noticeably affected by tannins. The description is based on adult males, pharate male pupae and one attached larval skin. The new species is assignable to the H. marcidus species group with some exceptions. Males differ from the previous group by a reduced number of rather weak, short acrostichal setae (0-3, previously considered as typical of the subpilosus group) as well as by a very reduced wing squamal fringe compared to most members of the H. marcidus group. Males are recognizable by an elongate, thin virga, distinctive anal point and inflated/triangular gonostylus. The female is not described; the immature stages are very similar in some features to H. boltoni. At the inland stream, an adult male of the new species was found together with pharate male pupae (one with larval skin) of another, as yet undetermined species of Heterotrissocladius (marcidus group) also known from elsewhere in the state. Female adults and a pharate female pupa collected at the blackwater stream site are noted but not included in the description or type series.
ISSN:1129-5767
1723-8633
DOI:10.4081/jlimnol.2018.1795