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brown Carabid - Agonum lutulentum

brown Carabid - Agonum lutulentum
Medford, (~25 miles east of Philadelphia, PA) Burlington County, New Jersey, USA
June 1, 2008
Size: ~7.3mm
here's a nice brown Carabid. further suggestions welcome :)

came to UV light

Images of this individual: tag all
brown Carabid - Agonum lutulentum brown Carabid - Agonum lutulentum

Thanks Peter,
Starting from the genus, yes, this one does appear to key to A. lutulentum. Matches LeConte's type at the MCZ well also. Of note, the MCZ has this listed under "A. lutulentus", ending with an 's', matching the species label shown with the beetle. A check on ITIS has "A. lutulentum" as valid, and no record of "lutulentus".

Another case of sloppy nomenclature
in which former name Platynus lutulentus is gender-consistent but later citations frequently perpetuated gender mismatch as "Agonum lutulentus".

thank Peter, but I'm so ignorant I don't understand your comment. Are you saying there are latin grammer rules which change the species name depending on the gender of the Genus name? Is there a reference you can recommend so I can learn these things? (there's probably a second grader somewhere that can school me)

Yes, gender of genus and species should be same.
If I recall correctly Platynus lutulentus is masculine; Agonum lutulentum is neuter. I'll double check this later. Off hand I can't recall a specific reference that would be useful to you.

Some guidelines for Latinized gender.
Masculine endings: -us, -ys, -ops,
Feminine endings: -a (except -ma neuter), -is, -yx
Neuter endings: -um, -om, -on, -ma

This is only a partial list so I may return to it later. There are complications, for example, -es ending could be either feminine or masculine.

Moved from Ground Beetles.

Agonum (subgenus Europhilus) likely.
Blackish head which contrasts with equally brownish pronotum + elytra favors member Agonum lutulentum in that subgenus. Members are easily separated by scoping.

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