Species Tibicen linnei - Linne's Cicada
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Class Insecta (Insects)
Order Hemiptera (True Bugs, Cicadas, Hoppers, Aphids and Allies)
Suborder Auchenorrhyncha (Free-living Hemipterans)
Family Cicadidae (Cicadas)
Genus Tibicen (Annual Cicadas)
Species linnei (Linne's Cicada)
Synonyms and other taxonomic changes
Mistakenly referred to by several authors as Carolus Linnaeus' Cicada tibicen. First described as a new species in 1907 by John B. Smith and John A. Grossbeck, as Cicada linnei
Explanation of Names
Named after Carolus Linnaeus
- Linné is the Swedish version of his name. Several authors had mistaken this species for one described by Linnaeus until Smith and Grossbeck set the record straight. It thus, ironically, became known as Linné's Cicada because it was shown not
to be his cicada at all, but a new species.
Usually characterized by the following (this taxon may be subject to considerable variation across its range):
1) Typically described as possessing an "uninterupted black face mask" (However, this trait is variable, esp in the south)
NOTE the strongly interrupted face mask in this Alabama specimen.
2) "Strongly bowed costal margin"
This trait is typical of most linnei populations but subject to variation. Unfortunately, this character may also be seen in several closely related taxa (esp. canicularis, winnemanna & pruinous in part) and may not be a dependable character as a stand alone diagnostic.
3) "Ventral black stripe on abdomen"
Subject to some variation, but seems reliable for most populations.
4) Eye color: This particular characteristic sparks debate for several taxa. As with most "single characters", this trait may not hold true across the range and can be subject to variation!
Among most populations, the eyes are usually dark (esp. the Southeast and Atlantic coast), but browns, greens, blues and greys may not be uncommon across parts of the "linnei range". It is worthy of mention that most specimens observed with lighter eye colors were in fact younger adults within the first 36 hours post emergence.
Side Note: It has also been observed and reported that "flash photography" may skew eye color in some insects (a side effect of photography & typical for skewing color in many insects). Here in the East, the eye color is dark (except in tenerals - in which it may be green, tan, brown, grey or slate). There may be more variation in the northern and western parts of the range (Great Lakes region) - however - it is also suspected there may be introgression among related taxa in this part of the range (more work is needed to substantiate the hybrid hypothesis)
5) females appear to lack the well developed pruinose spots at the base of the abdomen and may on occasion have slight indications at best
6) males usually have elongated and slightly pointed opercula (refer to image above) which are often dark in color, but NOT always (Usu. not evenly rounded as in pruinosus, but some populations exhibit very rounded opercula)
7) Although the song is often described as "fairly consistent" across most of the range (Davis describes the call as a rapid Zeger-Zeger-Zeger....), this "species" may in fact be as varied geographically in call as are some of the other Tibicen species in color and pattern. Others have decscribed the call as a rapid "whirring rattle" (~like gravel being swirled in a tin can).
Most similar in appearance and often confused with T. pruinosus, T. winnemanna, and T. canicularis
NOTE: Some IMAGES under this taxon may be MISIDENTIFIED and are in a constant state of review!
Based on morphological characteristics, call similarities, and distribution patterns, several species are subject to confusion and erroneous id (We/I make mistakes!).
This is a dynamic "living-breathing" site and though we (I) make mistakes, we strive to share the most comprehensive and accurate information possible.
Comments, corrections and updates are always welcome.
Eastern US and adj. s. Canada
Southeast: Most of the southeast (areas east of the Mississippi River)
Confirmed reports from the following locations: n. AL, e. AL, TN, GA, n. FL, c. FL, SC, NC, & VA
Questionable reports from MS, LA, & AR - ???
(NOTE: In central Florida, typical T. linnei is replaced by a strange variant endemic to the forests surrounding lime sinks and spring rivers along the highland ridge. The males in these populations often produce strange pulsing calls which deviate from typical linnei and often seem to possess hybrid linnei x pruinosus traits. These "linnei" populations need greater taxonomic scrutiny to better understand placement and taxonomic status.)
Mid-Atlantic & Northeast (Common to Locally Common)
New England (rare in extreme s. New England)
Mid-West & Great Lakes regions (Common to Locally Common)
Upper Plains States incl. Iowa & s. Wisconsin (Common to Locally Common)
Eastern Plains States (less common - KS & NE)
Some populations in the upper mid-South/central TN seem to prefer Junipers
June-October, Most places
September-November, central Florida
various hardwoods & conifers
"The TROUBLE with linnei"
T. linnei VS. T. pruinosus/winnemanna
Diagnostics such as the "line bisection test" & "wing node position" used to separate T. linnei from T. pruinosus in the Midwest - seems to be challenged when applied to "T. pruinosus/winnemanna" (+ other taxa) in the Southeast. I have noticed that while the point of bisection varies in T. winnemanna in the east and T. pruinosus from the upper mid-South, it nearly always bisects the designated wing cell somewhere across the last half or third. This point of bisection is often very near, on the point of coalescence, and in some cases even anterior to the point of coalescence between the C (costal vein) & SC (subcostal) - a characteristic predicted for T. linnei. Midwestern conventions and use of this test suggest little if any bisection of the designated wing cell in members of the pruinosus group.
In support of the test, the point of bisection is "relatively consistent" in most T. linnei and crosses the halfway point nearly everytime either on the point of coalescence (in females) or anterior to the point of coalescence (usu. males).
NOTE: Some variation exists between males and females of T. linnei and among populations of T. linnei. The "line bisection test" is not an ABSOLUTE. Even for T. linnei, there have been populations and isolated specimens which DO NOT conform nor meet the expected test results!
Although this test has some support and validity in the upper Midwest, it is of little use if you wish to separate female specimens of T. winnemanna, T. pruinosus and T. linnei collected below the Mason-Dixon Line. Using this character and test, as a stand alone deciding factor, may result in erroneous identification.
I have had this discussion on numerous occasions with several leading cicada specialists and few of them weigh heavily on the costal margin diagnosis for identification of linnei or separation of it from similar related types.
Bowing in the costae and use of the "line bisection test" for species determination can fail. There is significant overlap in this trait and strong bowing in the costae can be seen in any of the following taxa: T. linnei, T. pruinosus, T. winnemanna and T. canicularis (to a lesser extent T. robinsonianus). Due to overlap, it is not possible to separate the species based on this character alone.
Costal Margin used in id ... continued!
Please refer to the following paper for discussion on the idenification of T. linnei and separation of this species from other related species.
According to Beamer and supported in other manuscripts, the shape of the opercula of the males in T. linnei vs. T. pruinosus is the ONLY true deciding factor, not the wing shape.
NOTE: Opercula shape also varies in some populations of T. linnei! Collection of males while calling the typical "linnei call" has produced series of specimens with greater variation than suggested in the literature. Individuals have been collected from across the linnei range with observable variation in opercular shape and color, ranging from dark and elongated to oblique and pale (as seen and expected in "typical pruinosus").
The males' calls may be the only SINGLE useful character for species identification and separation (between pruinosus/winnemanna & linnei)! In parts of the range where linnei is sympatric with related taxa (esp. pruinosus/winnemanna), separation using traditional morphological characters may be moot (per. comm. & per. observ.).
Though not formally documented, hybridization appears to be common and widespread among several taxa. This species is part of a "taxonomic mess" involving T. pruinosus, T. winnemanna, and T. canicularis.... T. linnei often lies at the core, and is a "common denominator" among ambiguous taxa. As mentioned earlier, pruinosus/winnemanna and linnei may hybridize creating identification issues. Morphological and audal analysis seem to support crossing between and among several taxa incl. the aforementioned, however, more work ins needed to formally substantiate observations.
HYPOTHETICAL: Given the variation in morphologies and calls, "T. linnei" may belong to a complex involving potentially more than one species (?)
"Green Tibicen Species"
Collectively, yet informally, referred to as the "Green Tibicen species" (per. comm.), the following cicadas are often difficult to differentiate and all appear to be very closely related. Genitalic analysis of the males suggest these species are very closely related and morphological differences between and among the species are slight. It is also thought (based on observations) that several of these may be involved in complex hybrid zones; however, more work is needed to substantiate and better understand these observations.
Tibicen pruinosus pruinosus var. fulvus Beamer 1924 [syn. T. pruinosa var. fulva], "Pale Scissor(s) Grinder Cicada"
"Southern Dog-day Cicadas"
Loosely & informally referred to as the "Southern Dog-day Cicadas" (suggested - Reynolds 2010), the following taxa are mostly "southern" in distribution and appear to be closely related. These cicadas share several traits, incl. elongated opercula in the males, rapid trill and/or clicking calls, and unusually wide heads relative to body dimension (head widths usu. exceed thoracic widths).
(*appears to be the most divergent member within this group - ??)
Entomological News, v.18, p.127
Smith & Grossbeck's original description of the species.