Artificial Key to Cisthene Moths of Texas - The Key

In the previous journal article, I introduced the topic of constructing an artificial key to the 12 species of the lichen moth genus Cisthene which have been reported in Texas. The present article offers the identification key, along with selected illustrations and links to each of the twelve species. A third installment of this journal entry will have more detailed species descriptions along with updated range information. Here are the twelve species of Cisthene which have been reported in Texas, along with links to representative examples:

#8059 Cisthene subrufa (Barnes & McDunnough, 1913)
http://www.boldsystems.org/index.php/Taxbrowser_Taxonpage?taxon=Cisthene+subrufa&searchTax=Search+Taxonomy
#8060 Cisthene unifascia Grote & Robinson, 1868 http://bugguide.net/node/view/725219
#8061 Cisthene kentuckiensis (Dyar, 1904 http://bugguide.net/node/view/1131852
#8066 Cisthene tenuifascia Harvey, 1875 http://bugguide.net/node/view/90495
#8067 Cisthene plumbea Stretch, 1885 http://bugguide.net/node/view/1228517
#8070 Cisthene angelus (Dyar, 1904) http://bugguide.net/node/view/578042
#8071 Cisthene subjecta Walker, 1854 http://bugguide.net/node/view/1206008
#8072 Cisthene packardii (Grote, 1863) http://bugguide.net/node/view/1355054
#8073 Cisthene conjuncta (Barnes & McDunnough, 1913) http://bugguide.net/node/view/806771
#8074 Cisthene barnesii (Dyar, 1904) http://bugguide.net/node/view/309878
#8075 Cisthene picta (Barnes & McDunnough, 1918) http://bugguide.net/node/view/911893
#8078 Cisthene martini C.B. Knowlton, 1967 http://bugguide.net/node/view/321518

Fig1 Cisthene geography_4964.JPG
Figure 1. Thin-banded Lichen Moth, Cisthene tenuifascia, showing key elements used in the identification key.

ARTIFICIAL KEY TO TEXAS SPECIES OF CISTHENE:

1a. Color areas on FW mainly whitish; PM band consists of only a rectangular spot on costa and a rounded spot on inner margin; white basal streak partly separated from marginal PM spot by a gray patch or by more gray along inner margin; rare, mainly LRGV. #8073 C. conjuncta (Fig. 1-1)
I propose the common name "White-streaked Lichen Moth" for this species.
Fig 1-1 Cisthene conjucta TX-TxLepSurv-BG copy
1b. Color areas mainly orange, ranging from yellow to red-orange. (2)

2a. Basal streak separated from inner margin of FW by gray (Fig. 2-1)*; narrow edge of yellow present along much of costal margin; East Texas. (3)
(* This does NOT refer to the gray central disk on the thorax in many species.)
Figure 2-1 Cisthene packardii

2b. Basal streak contiguous with inner margin of FW (Fig. 2-2). (4)
Figure 2-2 Cisthene tenuifascia

3a. Basal streak meets marginal PM spot at apex of spot; basal streak mainly reddish, contrasting little with thorax, collar, and marginal PM spot; costal PM spot low, flattened, usually 2X to 3X wide as tall; uncommon in n.e. Texas. #8071 C. subjecta (Fig. 3-1)
Subject Lichen Moth
Fig 3-1 Cisthene subjecta FL1206008-Goss-BG

3b. Basal streak meets marginal PM spot below apex of spot; basal streak usually yellowish, contrasting with reddish on thorax, collar, and PM spots; costal PM spot mixed red and yellow, semicircular, with steep forward edge; e. 1/3 of Texas, west to Bastrop Co. #8072 C. packardii (Fig. 3-2)
Packard's Lichen Moth
Fig 3-2 Cisthene packardii LA7717305-Tyler

4a. Thorax, including central disk, entirely yellow or orange (Fig. 4-1) or with just a small streak of gray in rear center; basal orange streak broadly connected to PM band. (5)
Fig 4-1 Cisthene picta TX911893-Hendrickson-BG

4b. Thorax with gray central disk (Fig. 4-2). (6)
Fig 4-2 Cisthene unifascia_5184

5a. Axis of PM band perpendicular to inner margin; distal edge of orange PM band clearly concave; basal streak with straight lower (forward) margin; Edwards Plateau, High Plains, eastward; uncommon. #8075 C. picta (Fig. 5-1)
Pictured Lichen Moth
Fig 5-1 Cisthene picta TX911893-Hendrickson-BG

5b. Axis of PM band oblique, nearly parallel with outer FW margin; distal margin of PM band relatively straight (but flaring at costa); in Texas primarily in the Trans-Pecos, east to the Devil's River. #8070 C. angelus (Fig. 5-2)
Angel Lichen Moth
Fig 5-2 Cisthene angelus TX8915595-LeeHoy

6a. PM spot usually absent on costa, but extensive yellow-orange streak extends along costa (1/2 to full length, variable); PM spot on inner margin typically large, rounded or triangular; ground color medium gray; common in wooded East Texas, west rarely to Travis and Uvalde Cos. #8067 C. plumbea* (Fig. 6-1)
Lead-colored Lichen Moth
Fig. 6-1 Cisthene plumbea_3200
(* Highly variable amounts of yellow-orange; sometimes very extensive; see Fig. 6-2.)
Fig 6-2 Cisthene plumbea TN7620729-Kueda

6b. PM band complete or at least costal PM spot obvious. (7)

7a. Top of head (vertex) gray (but collar and tegulae usually orange)*; basal streak narrow; PM orange band typically very narrow or broken into 2 or 3 spots or virtually absent, often slightly convex on distal edge; primarily West Texas and Edwards Plateau, east to Austin. #8074 C. barnesii (Figs. 7-1, 7-2)
Barnes' Lichen Moth
(* Some C. plumbea may have gray head; see couplet 6.)
Fig 7-1 Cisthene barnesii TX5852279-Lasley Fig 7-2 Cisthene barnesii AZ1838416-Hannawacker

7b. Top of head orange or yellow (along with collar and tegulae) (Figs. 1, 4-2, etc.). (8)

8a. Primarily LRGV, uncommon: color areas pale yellow; basal streak stopping well short of PM band, the pair of short basal streaks along with the pale tegulae thus creating an elliptical patch around the dark thoracic disk; PM band variable but usually flares much wider at inner margin then at costa, or PM band broken with large triangle on inner margin, small one on costa; ground color brownish gray, often darker next to PM band or triangles; size small (FW 6 to 7 mm; wingspan 13 to 16 mm). #8059 C. subrufa (Fig. 8-1)
I propose the common name Tamaulipan Lichen Moth for this species based on its general distribution.
Fig 8-1 Cisthene subrufa Kons-Borth-BOLD

8b. Not as above; color areas typically orange to red-orange (occasionally yellow); basal streak usually reaching PM band or close to it, sometimes broadly connected; PM band usually complete, wide to thin, sometimes broken; ground color typically slate gray to blackish. (9)

9a. Ground color black; basal streak wide and widely connected to wide PM band; PM band with rounded, concave forward margin; extreme n.e. Texas only. (Color areas may be orange or yellow; ground color of worn specimens will be grayer.) #8061 C. kentuckiensis (Figs. 9-1, 9-2)
Kentucky Lichen Moth
Fig 9-1 Cisthene kentuckiensis MD1131852-Jonn-BG Fig 9-2 Cisthene kentuckiensis TX7140617-Annikaml

9b. Ground color dark gray to slate gray; basal streak variable but not broadly connected to PM band if at all; PM not shaped as above. (10)

10a. PM band typically consisting of two broad-based triangles which barely connect in middle; forward edge of PM band thus deeply indented, angular, irregular (not smoothly concave); color areas usually pale orange but may be yellow or red-orange; s.e. 1/2 of Texas. #8060 C. unifascia (Fig. 10-1)
One-banded Lichen Moth ("Banded Footman" in early literature)
Fig 10-1 Cisthene unifascia TX5451612-Lasley

10b. Not as above: PM band complete and of more uniform width and/or forward edge smoothly concave. (11)

11a. Color areas usually dark red-orange, often with very narrow yellow edge; ground color dark gray to blackish; rare, local in mts. of Trans-Pecos (poss. specimens). #8078 C. martini (Fig. 11-1)
Martin's Lichen Moth
Fig. 11-1 Cisthene martini AZ321518-Melton-BG

11b. Color areas typically orange; ground color slate gray; orange basal streak and PM band variable but usually relatively narrow, parallel sided or slightly concave on both edges, sometimes broken; common and widespread across much of Texas. #8066 C. tenuifascia (Figs. 11-2, 11-3, 11-4)
Thin-banded Lichen Moth
Fig 11-2 Cisthene tenuifascia_4964.JPG Fig. 11-3 Cisthene tenuifascia_7073 Fig 11-4 Cisthene tenuifascia TX5451615-Lasley
(Make sure to note the orange vertex, as noted on each of these examples.)

Supplemental Notes
As can be discerned from the structure of this key, the Thin-banded Lichen Moth is best identified by process of elimination. Yet it appears to be the most widespread species in Texas and, frustratingly, one of the most variable. To rephrase much of the information in the above key in a negative way, a Cisthene moth might be identified as Thin-banded IF it LACKS all of the following characters:

-- Gray separating the basal streak from inner margin ( = Subject or Packard's Lichen Moths)
-- Gray vertex ( = Barnes' Lichen Moth)
-- Orange thoracic disk ( = Pictured and Angel Lichen Moth)
-- PM band of two (or just one) broad spots or triangles ( = One-banded or Lead-colored Lichen Moth)

Indecision/confusion will occur if it can be demonstrated (e.g. by barcoding or genitalic examination) that some of the above characters can be documented in individuals of Thin-banded, but those occurrences are apparently very few in number, if they exist at all. A detailed discussion of the identification of Thin-banded Lichen Moth will be found in my next journal entry (Sept. 27, 2017). The most likely confusion among Texas members of this genus will be with the following:

-- Barnes's Lichen Moth can have (usually has?) an orange collar contrasting with the gray vertex. Failure to note the gray vertex and/or confusion of the collar and vertex color patches has led to many apparent misidentifications. Confusion arrises with Thin-banded because both species not infrequently have a very thin or broken PM band, but that condition is more frequent, perhaps the norm, in Barnes'. Observers should rely more on vertex color than PM band strength for identification. By range, Barnes' seems to be a moth of pinyon-juniper foothills and is unexpected (in Texas) outside of the Trans-Pecos and the southern and eastern Edwards Plateau.
-- Kentucky Lichen Moth has thus far only been documented in extreme n.e. Texas (Caddo Lake area). The black ground color (on fresh specimens), wide orange basal streak, and wide PM band normally distinguish this easily from Thin-banded, but faded individual Kentucky Lichen Moth which have somewhat narrower orange streaks and band may be confusable with Thin-banded having wider than normal color areas. Any confusion with One-banded is usually easily resolved with reference to the shape of the forward edge of the PM band. Confusion with Pictured Lichen Moth is resolved by thoracic disk color and the broader connection of the basal streak to the PM band in that species.
-- The enigmatic Tamaulipan Lichen Moth of the Lower Rio Grande Valley is known from few specimens and many images are suspect, thus I relied almost exclusively on BOLD specimens (see link above). Along with the short basal streak and brownish ground color, size is critically important. Based on published measurements, most/all Tamaulipan should be recognizably smaller than most Thin-banded. Keep your millimeter rule handy when in the LRGV (and everywhere else)!!

I emphasize again that the above key should be useful for identifying the majority of specimens and images, but uncommon or aberrant forms will not key out successfully, and the full range of variation in each species is still not easily examined solely from online images.

NOTE: This should be considered a DRAFT publication. I retain all rights to its content and subsequent publication. Please contact me (iNat message) for further details about development of the full article (in prep.).

Photo credits: (All photos by @gcwarbler unless noted otherwise.)
Fig. 1-1 Texas Lepidoptera Survey, BugGuide, used by permission.
Figs. 2-1, 3-2 @royaltyler, iNaturalist.org, used by permission.
Fig. 3-1 Gary J. Goss, BugGuide, used by permission.
Figs. 4-1, 5-1 Ann Hendrickson, BugGuide, used by permission.
Fig. 5-2 @leehoy, iNaturalist.org, used by permission.
Fig. 6-2 @kueda, iNaturalist.org, used by permission.
Fig. 7-1, 10-1, 11-4 @greglasley, iNaturlist.org, used by permission.
Fig. 7-2 @hannawacker, iNaturalist.org, used by permission.
Fig. 8-1 Spec. by Kons & Borth; BOLD public data, #HKONB166-08
Fig. 9-1 Jonn, BugGuide, used by permission.
Fig. 9-2 @annikaml, iNaturalist.org, used by permission.
Fig. 11-1 Copyright Charles W. Melton, BugGuide, used by permission.

Posted by gcwarbler gcwarbler, September 21, 2017 13:41

Comments

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Very impressive. That sort of work takes a lot of time and dedication. How did you settle on that group for a key, and did you have formal training to do that?

Posted by mamestraconfigurata over 1 year ago (Flag)
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Thanks, @mamestraconfigurata. The choice of doing a key for Cisthene at this time was somewhat serendipitous, but it was prompted by my own head scratching over several recent iNat observations. (My thanks to @kimberlietx, @leehoy, and Ann Hendrickson, among others, for that honor.) The set of 12 species covered here includes all species reliably reported to date in Texas from all the sources I could find. I'm not a trained entomologist or lepidopterist, per se, but I've been studying insects and moths as a "well-seasoned enthusiast" for decades. I have a strong biology background and have been using and constructing dichotomous keys for many years; I taught a session on the use of dichotomous keys for a local chapter of Master Naturalists a few years ago.

Posted by gcwarbler over 1 year ago (Flag)
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I think most of the moths were described by "well-seasoned enthusiasts" ! It's something I would like to do at some point (designing a key), but I actually don't know how to start or which group needs a key. I'll keep searching and playing around, though.

Ian

Posted by mamestraconfigurata over 1 year ago (Flag)
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Great work, Chuck! I remember making a key as a biology undergrad, after running across a book in the library that described the process.

Ian, there are some good YouTube videos on the process. Groups that need keys tend to be the ones in which the species are not readily distinguished just by looking at them--the key helps one to focus on the characters that are informative:
https://www.youtube.com/results?search_query=how+to+make+a+dichotomous+key

I once made a key to identification of Texas snake skins (well, the one's likely to be found around my home, anyway)....have long since lost it though!

Posted by pfau_tarleton over 1 year ago (Flag)
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Well done Chuck! I know this took a lot of time on your part, and it is very much appreciated! I'm bookmarking this page for the next one that shows up. And there better be a lot more! I'm ready to put my keying skills to work!

Posted by kimberlietx over 1 year ago (Flag)
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@pfau_tarleton Thank you very much for that!

Posted by mamestraconfigurata over 1 year ago (Flag)
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Chuck, this is fantastic! I didn't realize how confusing the Cisthene species were until I observed several in east Texas this year. I have bookmarked this excellent key, and will go back and look at my observations. I'm sure I will have to make some adjustments. Thanks again!

Posted by annikaml over 1 year ago (Flag)
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Great work, Chuck. Don't stop now - how about Acronicta?

Posted by krancmm over 1 year ago (Flag)
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Great work!, thanks for the corrections you made on mexican observations!
Revisen esta información: @juancarlosgarciamorales1 @hugoalvarezg @juancruzado

Saludos!

Posted by aztekium_tutor over 1 year ago (Flag)
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Oh, yeah! Acronicta next, Chuck!

Posted by annikaml over 1 year ago (Flag)
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So excited. I dreaded seeing Cisthene on my sheet... Now I can't wait.

Posted by benhutchins over 1 year ago (Flag)
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I vote Petrophila next!

Posted by benhutchins over 1 year ago (Flag)
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Chuck, I love this key!

Posted by annikaml over 1 year ago (Flag)
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I've just turned in a manuscript entitled "Identification of Cisthene Lichen Moths of the Central and Eastern US" to Southern Lepidopterists News. It has a more comprehensive description of all these species. That should be in print by mid-winter.

Posted by gcwarbler over 1 year ago (Flag)
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Chuck, looking forward to seeing it in print! How many () did you use? :)

For those of you who aren't familiar with Southern Lepidopterists News, it's the official publication of the Southern Lepidopterists Society which focuses on leps found in the southern US (Alabama, Arkansas, Florida, Georgia, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, Texas and Virginia). Membership dues are reasonable and the content is much more geared to our area than others, like the Lep Society's publications.

http://southernlepsoc.org/?cat=9

Posted by krancmm over 1 year ago (Flag)
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(Well, if you must know) I think (perhaps I'm just hoping) I didn't (or wouldn't--after your kind remarks/edits (although editorially--and grammatically--very helpful)) use too many parentheses or "brackets"--not that I think I've ever been guilty of inserting too many [because I always try to write succicntly and to the point with nothing repetitive, redundant, or duplicative included, and my shift-9 and shift-0 keys still seem to be working--but, of course, I wouldn't want them to get lonely]. (;-))

Posted by gcwarbler over 1 year ago (Flag)
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This journal entry has been edited, combined with the previous entry, and formally published in Southern Lepidopterist's News (Vol. 39, No. 4, pp. 309-322, Dec. 2017). A pdf of the final article is available from me; please send me a separate personal message on iNat if you are interested.

Posted by gcwarbler over 1 year ago (Flag)
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wow - I love this!

Posted by loarie over 1 year ago (Flag)
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Totally ditto on the love. This is indeed great. :)

Posted by sambiology over 1 year ago (Flag)
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The article is wonderful!! Looks great - you guys take up Chuck's offer for the .pdf as it's invaluable. Thanks @gcwarbler Chuck and @hughmcguinness Hugh.

Posted by krancmm over 1 year ago (Flag)

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