A Sprinkle of Earth
Neodiplogrammus quadrivittatus - Sesbania Stem-boring Weevil (Olivier, 1807)
The Price of Winning Worthless Fights
Old cellphone picture. Posting for the register.
Description: These weevils are members of the order Coleoptera, suborder Polyphaga, infraorder Cucujiformia, superfamily Curculionoidea, family Curculionidae, subfamily Molytinae, tribus group Cryptorhynchinae, tribe Cryptorhynchini and subtribe Cryptorhynchina.
Neodiplogrammus quadrivittatus is originarily from South America and is considered "beneficial", a bad term which simply means they don't give humans monetary damage. In Brazil, they are registered for the state of São Paulo (one registered sighting) and Rio Grande do Sul, but I found this one in Santa Catarina, a neighbor state. They feed on Sesbania punicea ((Cav.) Benth) (Fabaceae: Faboideae: Sesbanieae), Cassia corymbosa (Lamk) (Fabaceae: Caesalpinioideae: Cassieae: Cassiinae) which seems to be a synonym of Senna corymbosa ((Lam.) H.S.Irwin & Barneby), and Sesbania virgata ((Cav.) Pers.) (Fabaceae: Faboideae: Sesbanieae). To the latter was attributed the sighting of the beetle in the state of São Paulo. The beetles measure around 13mm in length and possesss predominantly black elytra and yellowish-colored stripes on along each elytron, along each leg and on the lower surface of the abdomen. The thorax is red or orange with irregular lateral black spots and an irregular median black spot with light spots above and below it. The head is black with parts about the same color of the stripes on the elytra. They can often be registered through the tunnelling behavior of the immatures, which destroy important vascular tissues restricting water movements and nutrients in the plant. The stems will most likely die because this behavior comes often along with the cutting of vascular contacts between the roots and the stem.
The impregnated female will lay single eggs under the bark of stems and branches of the host plants. The immature grubs will feed inside the wood of the plants just below the bark, moving downwards, destroying tissue in the process and often reaching the root crown. They take several months to reach maturity to pupate. The pupa is a rough cocoon constructed from chips of chewed wood. The eggs of Neodiplogrammus quadrivittatus take a long time to hatch; about a year and the reason to this is unknown to me.
The Neodiplogrammus quadrivittatus is yet another case of human interference in nature by introducing them to other areas to control the population of Sesbania sp. trees as, as few as three immatures are enough to down a tree. This human interference might actually be problematic in the long run. This interference went further along with the "help" of Rhyssomatus marginatus ("seed feeder") and Trichapion lativentre ("flower bud feeder"). N. quadrivittatus are univoltine (reproduces once a year), of poor dispersal and takes a long time to mature.
With these three natural enemies of Sesbania sp. trees present, the seeds become scarce and old trees die. This successfully gave humans levels below economic thresholds but, although large populations of N. quadrivittatus have scattered to isoated plants or small clumps, seemingly posing no threat to ecosystem functioning, it is hard to predict how bad this can get in the future. If a threat is posed against the ecosystem, another biological control will most likely be implemented to annihilate the weevils, possibly bringing even more ecosystem destruction in which the innocents pay the price. While the control of the trees might be important now, it is just a consequence of more human intervention. This introduction is used because the course of control is gradual. Introduced plants or insects are, in reality and in most of the cases, if not all (to be politically correct), the result of human intervention in which many and innocent lives are scythed due to the truth behind the curtains: money. The spotting of a N. quadrivittatus in São Paulo possibly means that they can move on to other areas. I could find no registers of them in Santa Catarina, further reinforcing that it is unpredictable what will happen long term and who will pay the heaviest price once their introduction to other places become widespread. The chances are low due to their low dispersal process, but not impossible. They can also be found in Argentina, South Africa and possibly other places.
The males of N. quadrivittatus are smaller than females (www.inaturalist.org/taxa/417295-Neodiplogrammus-quadrivit...). The subject portrayed in this post is most likely a female.
Their habitats became forests containing their host plants within their zone of distribution and introduction.
Further sources:
www.scielo.br/scielo.php?pid=S1519-566X2003000300022&...
books.google.com.br/books?id=li5gq1pqR3kC&pg=PA145&am...
www.ncbi.nlm.nih.gov/pubmed/28307777
www.arc.agric.za/arc-ppri/Pages/Red-sesbania.aspx
PROJECT NOAH (Português): www.projectnoah.org/spottings/1622169192
Neodiplogrammus quadrivittatus - Sesbania Stem-boring Weevil (Olivier, 1807)
The Price of Winning Worthless Fights
Old cellphone picture. Posting for the register.
Description: These weevils are members of the order Coleoptera, suborder Polyphaga, infraorder Cucujiformia, superfamily Curculionoidea, family Curculionidae, subfamily Molytinae, tribus group Cryptorhynchinae, tribe Cryptorhynchini and subtribe Cryptorhynchina.
Neodiplogrammus quadrivittatus is originarily from South America and is considered "beneficial", a bad term which simply means they don't give humans monetary damage. In Brazil, they are registered for the state of São Paulo (one registered sighting) and Rio Grande do Sul, but I found this one in Santa Catarina, a neighbor state. They feed on Sesbania punicea ((Cav.) Benth) (Fabaceae: Faboideae: Sesbanieae), Cassia corymbosa (Lamk) (Fabaceae: Caesalpinioideae: Cassieae: Cassiinae) which seems to be a synonym of Senna corymbosa ((Lam.) H.S.Irwin & Barneby), and Sesbania virgata ((Cav.) Pers.) (Fabaceae: Faboideae: Sesbanieae). To the latter was attributed the sighting of the beetle in the state of São Paulo. The beetles measure around 13mm in length and possesss predominantly black elytra and yellowish-colored stripes on along each elytron, along each leg and on the lower surface of the abdomen. The thorax is red or orange with irregular lateral black spots and an irregular median black spot with light spots above and below it. The head is black with parts about the same color of the stripes on the elytra. They can often be registered through the tunnelling behavior of the immatures, which destroy important vascular tissues restricting water movements and nutrients in the plant. The stems will most likely die because this behavior comes often along with the cutting of vascular contacts between the roots and the stem.
The impregnated female will lay single eggs under the bark of stems and branches of the host plants. The immature grubs will feed inside the wood of the plants just below the bark, moving downwards, destroying tissue in the process and often reaching the root crown. They take several months to reach maturity to pupate. The pupa is a rough cocoon constructed from chips of chewed wood. The eggs of Neodiplogrammus quadrivittatus take a long time to hatch; about a year and the reason to this is unknown to me.
The Neodiplogrammus quadrivittatus is yet another case of human interference in nature by introducing them to other areas to control the population of Sesbania sp. trees as, as few as three immatures are enough to down a tree. This human interference might actually be problematic in the long run. This interference went further along with the "help" of Rhyssomatus marginatus ("seed feeder") and Trichapion lativentre ("flower bud feeder"). N. quadrivittatus are univoltine (reproduces once a year), of poor dispersal and takes a long time to mature.
With these three natural enemies of Sesbania sp. trees present, the seeds become scarce and old trees die. This successfully gave humans levels below economic thresholds but, although large populations of N. quadrivittatus have scattered to isoated plants or small clumps, seemingly posing no threat to ecosystem functioning, it is hard to predict how bad this can get in the future. If a threat is posed against the ecosystem, another biological control will most likely be implemented to annihilate the weevils, possibly bringing even more ecosystem destruction in which the innocents pay the price. While the control of the trees might be important now, it is just a consequence of more human intervention. This introduction is used because the course of control is gradual. Introduced plants or insects are, in reality and in most of the cases, if not all (to be politically correct), the result of human intervention in which many and innocent lives are scythed due to the truth behind the curtains: money. The spotting of a N. quadrivittatus in São Paulo possibly means that they can move on to other areas. I could find no registers of them in Santa Catarina, further reinforcing that it is unpredictable what will happen long term and who will pay the heaviest price once their introduction to other places become widespread. The chances are low due to their low dispersal process, but not impossible. They can also be found in Argentina, South Africa and possibly other places.
The males of N. quadrivittatus are smaller than females (www.inaturalist.org/taxa/417295-Neodiplogrammus-quadrivit...). The subject portrayed in this post is most likely a female.
Their habitats became forests containing their host plants within their zone of distribution and introduction.
Further sources:
www.scielo.br/scielo.php?pid=S1519-566X2003000300022&...
books.google.com.br/books?id=li5gq1pqR3kC&pg=PA145&am...
www.ncbi.nlm.nih.gov/pubmed/28307777
www.arc.agric.za/arc-ppri/Pages/Red-sesbania.aspx
PROJECT NOAH (Português): www.projectnoah.org/spottings/1622169192