Tibicen pruinosus - Neotibicen pruinosus

Moved

… John R. Maxwell, 1 April, 2009 - 9:38pm

Tibicen pruinosus (MALE)

T. linnei has a a well defined glossy BLACK ventral stripe that is unbroken and bold...This cicada does not.

Comments regarding other traits listed under other pic's of this insect (pointing out characters as visible per image)

… Bill Reynolds, 20 March, 2009 - 3:22pm

Tibicen pruinosus

Typical example of T. pruinosus from much of the upper mid-south west of the Appalachians.

… Bill Reynolds, 3 March, 2009 - 4:12pm

Tibicen pruinosus complex

I agree with Dr. Hamilton, - this is no Tibicen linnei; however, I'm not convinced it is T. robinsonianus either. As stated, the opercula are much more rounded than seen in linnei; however, they still do not quite seem as short and rounded as T. robinsonianus. Tibicen pruinosus is a much more common species west of the appalachians (i.e Knoxville, TN) than here in the east (Raleigh, NC). Based on my experience in the region, Tibicen pruinosus can be quite abundant west of the mountains and esp. along the Tennessee River drainage of eastern TN (incl. Knox Co., TN) and n. Alabama (Madison Co., Lawrence Co., Colbert Co. & Lauderdale Co., AL etc.). I'm uncertain where (if at all) the break between the populations/species of T. winnemana and T. pruinosus occur, but I am certain that the distinctive call of T. pruinosus can be heard throughout the afore-mentioned region. A closer look at the other images of this insect, reveals that the dorsum of the abdomen seemingly lacks the tan/light brown markings typical of T. winnemana. There is also a distinctive elongated white mark immediately behind the tymbal cover, more suggestive of T. pruinosus. In support, using the 1922 original description of T. robinsonianus, this specimen lacks the black pigmentation, both dorsally and ventrally, in quantities sufficient to be suggestive of that species (T. robinsonianus). Since this insect has well developed ventral wax, it is not assumed to be teneral - explaining away the possibility of the black having not yet "developed". Additionally, this cicada lacks the sharply delineated, shiny black, ventral stripe along the midline seen in T. robinsonianus (and T. linnei). The dorsal aspect of the abdomen also seems to lack that glossy black characteristic of T. linnei and it's "sister sp." T. robinsonianus,... therefore, I lean towards T. pruinosus as a more likely id.

Refer to this image for T. robinsonianus - http://bugguide.net/node/view/8657/bgimage

… Bill Reynolds, 24 October, 2008 - 3:41pm

T. pruinosus complex

Another key that I am finding with regards to T. linnei vs T. pruinosus is the extremely broad black stripe which runs contiguously across the face between the compound eyes in T. linnei. See this photo here:

The specimen in this series of photos while having a stripe is not as defined and is broken up by the sclerotized portions of the head capsule. I would agree with Bill that this is probably a form of T. pruinosus and not T. robinsonianus for his points mentioned above.

… Gerry Bunker, 28 October, 2008 - 9:38am

Excellent Point !!!

As Gerry mentioned, T. linnei usually has a continuous "black mask" across the face (Thanks for that image Gerry - EXCELLENT POINT!). It is also important to note that T. robinsonianus shares this trait! Another shared similarity.

Based on my experience with these species (southern material), T. linnei and T. robinsonianus can be very difficult to separate - at least until you familiarize yourself with and isolate the differences between the 2 species (involving differences in the Costal Vein and Opercula). As mentioned by others here on Bugguide, T. linnei has a "notable bend/obtuse angle" in the costal vein, while T. robinsonianus has a more gradual curve. Regarding the opercula, as Dr. Hamilton pointed out, T. linnei has more elongated opercula, while those in T. robinsonianus are evenly rounded and truncated by comparison.

Thanks to Gerry's comment, a second and yet closer examination of T. pruinosus specimens on hand, revealed most specimens in this group, incl. winnemana & latifasciata, often possess green interruptions in the "black mask" (but not always!).

On another note, although I do not like to use color as an end all deciding factor in any id., based on material I have in my collection, the following seems to hold true:

The opercula in T. pruinosus are ochreous in color, while in most (not all!) T. linnei and T. robinsonianus the opercula are, at least in part, shaded with a darker brownish pigment anteriorly - a trait not yet seen in any of the pruinosus material I have examined.

… Bill Reynolds, 28 October, 2008 - 10:43am

Tibicen robinsonianus

Similar to T. linnei, but with rounder opercula (the brown flaps just behind the hind leg bases) and with the front wings less strongly angled at the node. It resembles T. canicularis, but has the wing node futher towards the base of the wing (below its midlength).

This species may in fact be a hybrid between T. linnei and T. canicularis. Do you have the latter in your neck of the woods?

… Andy Hamilton, 11 September, 2007 - 1:46pm

T. robinsonianus and it's possible Hybrid origin (?)

Although Tibicen robinsonianus is sympatric with both Tibicen linnei and T. canicularis, at least throughout parts of the latters' ranges, T. robinsonianus still appears to have a more southern distribution than does T. canicularis. I was recently informed that T. robinsonianus shares quite a few characters with T. linnei, - incl. many physical attributes and to some degree audal components, - suggestive of a more common recent ancestry between the two, =sister species (per. comm.). Hopefully more taxonomic work will be done in the near future to resolve this question. Until then, T. robinsonianus should be treated as a species.

… Bill Reynolds, 24 October, 2008 - 5:33pm

Tibicen robinsonianus

duplicate remark; the original did not show up until I had re-entered my comments.

… Andy Hamilton, 11 September, 2007 - 11:44am