segunda-feira, 28 de fevereiro de 2011
Localização geográfica: Estância Velha, Rio Grande do Sul. Data: 27 de fevereiro de 2011 (alto verão).
PS: poderia esta cigarra ser do gênero Proarna???
This video was made in a rare moment of luck! Too bad it lacked a little bit more luck to get to capture tha cicada ... But something I could see, for example, was its size, which is about 3cm. Her body was dark (brilliant conclusion! was dark when I shot ... lol) but had a few lighter spots. I even tried to distinguish something else, but when I approached to try to capture it, it flew away ... You can even hear my voice of devastation at the end of the video ... rs.
Geographic Location: Estancia Velha, Rio Grande do Sul Date: February 27, 2011 (midsummer).
PS: could this cicada belong to genus Proarna??
I know it's an awful picture, but i wanted to include it here anyway, so i could register the presence of a member of the Tibicen genus in Southern Brazil, on 2010's Christmas. Song is quite identical to Tibicen auriferus. Aproximate size: 3/4 inches.
quinta-feira, 24 de fevereiro de 2011
This is a recording of a cicada singing so low that it's almost inaudible (a succession of short calls... a "ki-ki-ki " very low). To be honest, I never saw the insect singer, but I'm sure it is a cicada because of the following reasons: 1. I don't know a cricket which makes a noise even similar, 2. I've never seen any cricket who sings in trees, even as high as the one shown in the video (maybe katydids could do that, but they don't sing during the day!) 3. The song is very similar to another species of cicada that i've already shown in this blog (Dorisiana viridis). For these reasons, along with the species' behavior (when two males are singing, they make a "duel"), I believe it's a cicada from genus Dorisiana, but the species I don't know (could be two species, D. drewseni or D . sp.) Someday I'll capture a specimen to photograph!
sexta-feira, 18 de fevereiro de 2011
Diferente da postagem anterior, na qual as fotos não forneciam muitos detalhes, as fotos desta postagem mostram os espécimes com nitidez. Pode-se ver claramente o desenho característico do "M" nas costas das cigarras (característica idêntica à do gênero Tibicen... por falar nisso, repararam na semelhança física??). Mais detalhes: Dorso - cabeça verde-escura (até o pronoto), mesonoto negro (com o M em verde-escuro) e abdome verde-escuro (com faixas verde-claro nas bordas dos segmentos). Ventre - cabeça verde-clara, tórax branco e abdome amarelado (quase bege), com os órgãos sexuais na cor marrom-escuro. Chamo a atenção para o rosto desta cigarra: olhando de frente, parece que ela está usando uma "máscara" sobre os olhos, e, o mais interessante, os olhos têm as duas cores do rosto!!! Vistos por cima, são escuros; por baixo, são claros!!
Já ia me esquecendo: o tamanho aproximado desta espécie é de 1,8 cm (razoavelmente pequena), e ela costuma ficar entre as folhas dos galhos (normalmente em árvores altas, mas encontrei esta em moitas baixas, em grande número). Costumam cantar em sincronia, mas às vezes cantam sozinhos.
A identificação desta espécie foi baseada nos seguintes documentos:
We're in February, and it's the Dorisianan invasion!! This genus is characterized by its emergence on late summer months (from January till March), and wherever I go I hear their song (ki-ki-ki-ki) in chorus echoing through the trees. The photos above show a female, I had the displeasure of collecting it already dead in my workplace. The bottom shows a male, alive, caught in my neighborhood and released shortly after the photo.
Unlike the previous post, in which the photos did not provide good details, these photos are very clear. You can clearly see the distinctive design of an "M" on the back of cicadas (identical to the characteristic of the genus Tibicen ... by the way, did you notice the resemblance?). More details: Back - dark green head (until the pronotum), black mesonotum (with the M in dark green) and abdomen dark green (light green with stripes on the edges of the segments). Belly - light green head, white thorax and light brown abdomen with the sexual organs in dark brown color. Pay attention to the cicada's face: it looks like it's wearing a "mask" over its eyes, and, most interestingly, the eyes are bicolor! Looking from above, they are dark, below, they are lighter!
Before I forget: the approximate size of this species is 1.8 cm (fairly small), and they usually stay between the leaves on the branches (usually in tall trees, but found this low in bushes in large numbers). They usually sing in sync, but sometimes they sing alone.
terça-feira, 15 de fevereiro de 2011
Yes I know, this is a blog about cicadas, but this bird is so uncommon in urban areas I couldn't resist so I decided to post it in my blog. It's the Common Potoo (Nyctibius griseus), and it occasionally makes a visit to the squarethat stands in front of my house. Before you ask me, yes it is possible that it feeds on cicadas (after all, it is insectivorous), but mainly it feeds on nocturnal insects (wich is not cicada's case). It has two distinct characteristics: its song, which is pretty sad, seems a regret (some say it is saying "gone, gone, gone ..." when it sings); and its ability to stand perfectly still, imitating a dead branch (thanks to two small holes in his eyelids, they can see even with eyes closed, thus ensuring their immobility until shortly before an imminent attack). There are many beautiful legends about this "ugly bird" but I will not repeat them here, just gonna let my record of their presence in my city (Campinas-SP).