Monday, May 6, 2013

Correction: That "long-horned case-maker" was genus Ceraclea (Ceraclea maculata), not genus Oecetis

I have one of our readers to thank for spotting a problem and helping me with this identification.

The long-horned case-maker I found at Buck Mt. Creek on Saturday (5/4) was Ceraclea by genus, not Oecetis.  In fact we can take it to species level ID -- it was Ceraclea maculata.  The maxillary palpi on Oecetis larvae are much longer than those you'll see in my previous photos.

For the genus ID let's go right to Wiggins (Larvae of the North American Caddisfly Genera, 1977 -- 1st ed.).

"Morphology  Larvae of Ceraclea are stout-bodied, the first abdominal segment widest and the abdominal gills usually in clusters.  The ventral apotome of the head is crescent-shaped and wider than long."   (Larvae, p. 164) Photos.

Wiggins continues, "In some species a parafrontal area is delimited between each frontoclypeal arm of the dorsal ecdysial line and a lightly pigmented supraocular line."  Need to illustrate that.

Genus Ceraclea.

On to species ID and the work of Steven Beaty ("The Trichoptera of North Carolina," p. 89).

C. maculata -- larvae 5-6 mm; parafrontal areas present; brown head with lighter spots on dorsum and side of head with 3 dark spots on pale background; 

The "parafrontal area" is illustrated in the picture above, and we can see the light spots on the dorsum and side of the head.  Not sure what he has in mind with the "3 dark spots."  This larva was 5 mm.

frontoclypeal lateral sutures parallel; pronotum light brown without contrasting spots; mesonotal bars sharply curved; two pair of setae on 9th tergite; anal leg with rod-like sclerites.  Case of fine grained sand often with larger sand particles incorporated, tapered and slightly curved.  Photos.

frontoclypeal lateral sutures (yes, parallel):

pronotum and mesonotal bars:

pairs of setae and anal leg sclerites (the orange slivers, not the dark brown):



That should be convincing.  Beaty adds that this species is "relatively common."  The TV is 6.2.

Another species is added to our EPT list of central Virginia.

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