A Study of an Extinct Butterfly Plebejus argus masseyi.
Dec 28, 2014 12:38:57 GMT
deliasfanatic, mygos, and 6 more like this
Post by nomad on Dec 28, 2014 12:38:57 GMT
The insect collections in the Hope Department of Entomology at the Oxford University Museum of Natural History in the UK are a hallowed ground for any visiting British entomologist. Here there are echos of many famous entomologists, these include the Hope Department's founder Frederick William Hope, the first curator- professor John Obadiah Westwood and the great naturalist Alfred Russell Wallace. The collections include thousands of historical worldwide specimens including many of those that were caught by Wallace on his adventures through the Malay archipelago and those by Darwin on the voyage of HMS Beagle.
The Oxford University Museum of Natural History.
Recently, I was at the museum visiting the British collections and during my study there, I was able to learn more about an extinct native butterfly and lesser known but distinguished naturalists who had collected and observed this butterfly in the field. I spent the day examining the Lycaenidae cabinets. There were several drawers of, in my opinion, the most interesting of our British butterflies, the Silver-studded Blue - Plebejus argus. In Britain Plebejus argus has an extraordinary amount of interesting geographical variation. As I drew out one cabinet drawer of Plebejus argus I knew its contents would be especially pleasing because it contained several rows of the two British extinct subspecies of Plebejus argus, cretaceus and masseyi. Extinct butterflies always have fascinated me, whether or not they are full species or subspecies. There are some species in far off jungles that have become extinct, but there is ever the hope of entomologists they still occur somewhere in an unexplored place. However, there is no hope for the extinct subspecies that I was about to examine, they really have departed both this once green and pleasant land forever. One advantage of studying the collections at the museum's Hope department, is that many of the specimen data labels have been transcribed and another label placed at its side on a pin where the details can be clearly seen. There is not need to physically examine the specimens. We all know to where that can lead to, the removal of data labels has seen specimen damage where antennae and abdomen and even wings have been broken by museum researchers.
I was especially interested in the museum's series of the extinct Plebejus argus masseyi. This race was first captured at Witherslack Moss by J.B. Hodgkinson ( 1823-1897) of Preston on July 21st 1856. Hodgkinson had started life in poverty, working long hours as a mill boy, but he still managed to become an expert field collector and native lepidoptera dealer. It then seems that this new mossland race of Plebejus argus was forgotten about until Herbert Massey from Manchester visited the locality in 1892, he had previously collected with Hodgkinson. Massey sent specimens of Plebejus argus from Witherslack to James Tutt, who at first wrongly ascribed this new race with its remarkable blue females to the endemic var corsica ( corsicus) -subspecies Bellier 1862. Later however, Tutt when viewing both the subspecies corsicus noticed that the British race had a much different underside and described the British subspecies in Massey's honour during 1909. Dr Chapman confirmed the genitalia of the males of both races, corsicus and masseyi were also different . The race masseyi differs from the nominate race argus that represents the lowland British heathland populations by the following features. The males are of a brighter blue with a reduced black border, revealing the nerves and spots on the forwings outer edges. The females are rayed with an almost metallic blue that covers most of the hindwing and much of the forewings.
Specimens of P. argus argus from lowland Heathland, Studland England that were captured during early July 1899 by W.G. Pogson Smith. OUMNH collections.
Left.Two male specimens of Plebejus argus masseyi caught by B.H. Crabtree during July 1915-1916 at Witherslack Moss. OUMNH collections. Right.Two female beautiful specimens of masseyi caught by C.F. Johnson at Witherslack Moss during July 1918. OUMNH collections.
Having viewed a series of Plebejus argus masseyi in a private collection that were captured from all the same historic locality, the Witherslack Moss Westmorland ( now part of Cumbria ) in Northern England ; I was not surprised at first to see that those in the museum's drawer were also from the same locality and from around the same date 1915-1919. It seems during those years at Witherslack Moss this beautiful little insect was at its most abundant and that is when the majority of collectors came here to add a series to their collection. Massey in the ' The Entomological Record and Journal of Variation ' for 1895 gave a short account of encountering subspecies masseyi at Witherslack. He mentions visiting in 1892 and found that masseyi occurred only in the wettest part of the moss where it was extremely local and it seemed to fly little. He mentioned that the peat cutters had started to dig on the moss and wondered if this would affect the butterfly. James Tutt in his ' A Natrual History of the British Lepidoptera Vol 10 - British Butterflies Vol 3' published in 1909, added the following notes ; At Witherslack Moss during 1897 Murray found masseyi flying among a very low species of rush about 3 inches - 7.62cm high in a place where no trefoil ( trifolium) occurs. Tutt noted that the collector Crabtree took masseyi in fine condition at Witherslack on the July 17-18th during 1893. From specimen data and other records masseyi had a short flight period and was on the wing between mid July and early August. On the colder northern wet mosslands, subspecies masseyi started to emerge later than P. argus argus in Southern England. Tutt mentions that on the mosses there was an abundance of Ornithopus perpusillus - Birds - foot ; although the foodplant of masseyi remains unknown. Even if the Victorian and later collectors could have found the larvae they would have not been able to breed this butterfly because it was not then known that Plebejus Argus has such a close assocation with Ants. Recently, detailed studies in the UK have found out here that Plebejus argus is more dependant on Ants ( Formicidae) through its entire larvae and pupae stages than any other British butterfly.
Left. Plebejus argus masseyi male verso specimen captured by C.F. Johnson during July 1918 at Witherslack Moss. OUMNH collections. Right Female masseyi specimen captured by E.J. Nurse during July 1918 at Witherslack Moss. OUMNH collections.
I had almost finished studying the cabinet drawer of masseyi in the museum when I noticed three specimens in the top left hand corner had been taken at a different locality, Holker Moss in Lancashire by a J. J. Lister. When Lister had discovered masseyi at Holker Moss in Lancashire during 1918, he found that here the females differed in some small degree to those females in the wetland colonies to the south and gave an interesting account in the ' Transactions of the Entomological Sociey of London for 1919. Holker Moss lies some 16 kms north of Witherslack moss near the estuarine part of the River Leven in North Lancashire, which is now also included in Cumbria. The two mosses are separated by high ground known as the Cartmell Fells. Indeed, until I read Lister's account I was not sure exactly where Witherslack Moss was in relation to the village of the same name. As limestone hills commence just north of the village I knew it was somewhere in the low-lying ground to the south. Witherslack Moss does not seem to appear on any maps that I have seen and as all the surviving fragments of other mosses are today sometimes now known as the Witherslack Mosses. I felt that it was important to locate the exact site of Witherslack Moss where subspecies masseyi was originally discovered . Lister records that the main masseyi site at Witherslack Moss was situated about a mile- 1.6km south of the village between the River Winster and the old road from Witherslack to Grange on the coast. To the east of the road lies the fragmented Meathrop Moss, which is now a local nature reserve and still has important populations of the northern and midland specialty Coenonympha tullia ssp davus .
Two female specimens of masseyi taken by J.J. Lister at Holker Moss during July 1919. OUMNH collections.
Lister found that in the females of masseyi from Holker Moss the blue scales were mainly confined to inner areas of the forewings and that the blue areas were much greater in those of the females from the Westmoreland mosses lying near the River Kent. This indicates that Lister has found masseyi on other mosses in the old county of Westmoreland other than at its prime locality at Witherslack. Lister mentions in his account that he had examined and compared 83 females in his collection from the River Kent mosses and 40 females from Holker Moss.
J.J. Lister certainly was a very enthusiastic collector who gave us valuable information on plebejus argus masseyi. Joseph Jackson Lister ( 1857 -1927 ) was born at Leytonstone in London, later he went to Cambridge University where he became a senior lecturer in Animal Morphology. In 1887-1888 he was chosen as the naturalist for the voyage of HMS Egeria to Christmas Island in the Indian Ocean where he discovered a number of new species. He has a Palm, Orchid and Gecko named in his honour. The ship then went on to survey Australia. He wrote a book, the Natural History of Christmas Island in 1888.
I have read that Plebegus argus masseyi finally because extinct around 1942 ( Thomas 1999). If indeed masseyi survived until that date, it must have been very rare by then. Radcliffe (2002) mentions that on several occasions he had been told that the last population of masseyi disappeared in a fire. There is a population of Plebejus argus in the Nature reserve at Prees Heath in Shropshire in the West Midlands which a number of people have referred to as subspecies masseyi. The habitat at Prees Heath is typical lowland heathland not wet mossland. The females in the Prees Heath are a mixture of the typical lowland argus with brown wings and those that have blue scaling, where on the forwings it is confined to the inner areas. There was also once another population of Plebejus argus at Delamere Forest in Cheshire which has also become extinct ; here the females were similar to those at Prees Heath. There was a mosaic of habitats at Delamere from heathland to mosses and it is not cetain which of these the population of Plebejus argus inhabited. While the population at the Shropshire site is most interesting, it sadly does not seem to be the extinct subspecies masseyi of the northern mossland sites. masseyi certainly was collected in large numbers and there must have been heavy pressure on its population. The Derby arms - Inn in the village of Witherslack where Lister and many other entomologists stayed and made it there base for their field excursions, was also the meeting place of local entomological field excursions. See the image below of one such entomological meeting at the Witherslack Derby Arms in 1904. When Lister and other collectors were enoying their days during 1918-1919 on the mosses , they probably did not know that a bill had been passed in London to drain Witherslack, Holker and some of the other mosses in the surrounding area. In the ensuing years both Holker and Witherslack mosses were indeed drained. Holker Moss became agricultural land and Witherslack moss was planted with a plantation of cash crops of conifers. So in the end it was habitat destruction by drainage and perhaps a disastrous fire and not collectors which saw the sad extinction of the charming little masseyi in its unique habitat. Only those little bright jewels in collections are a reminder of what we have sadly lost.
Entomological field meeting at the Derby Arms, Witherslack during 1904. When I stayed at the inn two years ago, the original photograph of this image was still hanging on the bar wall.
Holker Moss is now farmland. Sheep grazing the site.
The Oxford University Museum of Natural History.
Recently, I was at the museum visiting the British collections and during my study there, I was able to learn more about an extinct native butterfly and lesser known but distinguished naturalists who had collected and observed this butterfly in the field. I spent the day examining the Lycaenidae cabinets. There were several drawers of, in my opinion, the most interesting of our British butterflies, the Silver-studded Blue - Plebejus argus. In Britain Plebejus argus has an extraordinary amount of interesting geographical variation. As I drew out one cabinet drawer of Plebejus argus I knew its contents would be especially pleasing because it contained several rows of the two British extinct subspecies of Plebejus argus, cretaceus and masseyi. Extinct butterflies always have fascinated me, whether or not they are full species or subspecies. There are some species in far off jungles that have become extinct, but there is ever the hope of entomologists they still occur somewhere in an unexplored place. However, there is no hope for the extinct subspecies that I was about to examine, they really have departed both this once green and pleasant land forever. One advantage of studying the collections at the museum's Hope department, is that many of the specimen data labels have been transcribed and another label placed at its side on a pin where the details can be clearly seen. There is not need to physically examine the specimens. We all know to where that can lead to, the removal of data labels has seen specimen damage where antennae and abdomen and even wings have been broken by museum researchers.
I was especially interested in the museum's series of the extinct Plebejus argus masseyi. This race was first captured at Witherslack Moss by J.B. Hodgkinson ( 1823-1897) of Preston on July 21st 1856. Hodgkinson had started life in poverty, working long hours as a mill boy, but he still managed to become an expert field collector and native lepidoptera dealer. It then seems that this new mossland race of Plebejus argus was forgotten about until Herbert Massey from Manchester visited the locality in 1892, he had previously collected with Hodgkinson. Massey sent specimens of Plebejus argus from Witherslack to James Tutt, who at first wrongly ascribed this new race with its remarkable blue females to the endemic var corsica ( corsicus) -subspecies Bellier 1862. Later however, Tutt when viewing both the subspecies corsicus noticed that the British race had a much different underside and described the British subspecies in Massey's honour during 1909. Dr Chapman confirmed the genitalia of the males of both races, corsicus and masseyi were also different . The race masseyi differs from the nominate race argus that represents the lowland British heathland populations by the following features. The males are of a brighter blue with a reduced black border, revealing the nerves and spots on the forwings outer edges. The females are rayed with an almost metallic blue that covers most of the hindwing and much of the forewings.
Specimens of P. argus argus from lowland Heathland, Studland England that were captured during early July 1899 by W.G. Pogson Smith. OUMNH collections.
Left.Two male specimens of Plebejus argus masseyi caught by B.H. Crabtree during July 1915-1916 at Witherslack Moss. OUMNH collections. Right.Two female beautiful specimens of masseyi caught by C.F. Johnson at Witherslack Moss during July 1918. OUMNH collections.
Having viewed a series of Plebejus argus masseyi in a private collection that were captured from all the same historic locality, the Witherslack Moss Westmorland ( now part of Cumbria ) in Northern England ; I was not surprised at first to see that those in the museum's drawer were also from the same locality and from around the same date 1915-1919. It seems during those years at Witherslack Moss this beautiful little insect was at its most abundant and that is when the majority of collectors came here to add a series to their collection. Massey in the ' The Entomological Record and Journal of Variation ' for 1895 gave a short account of encountering subspecies masseyi at Witherslack. He mentions visiting in 1892 and found that masseyi occurred only in the wettest part of the moss where it was extremely local and it seemed to fly little. He mentioned that the peat cutters had started to dig on the moss and wondered if this would affect the butterfly. James Tutt in his ' A Natrual History of the British Lepidoptera Vol 10 - British Butterflies Vol 3' published in 1909, added the following notes ; At Witherslack Moss during 1897 Murray found masseyi flying among a very low species of rush about 3 inches - 7.62cm high in a place where no trefoil ( trifolium) occurs. Tutt noted that the collector Crabtree took masseyi in fine condition at Witherslack on the July 17-18th during 1893. From specimen data and other records masseyi had a short flight period and was on the wing between mid July and early August. On the colder northern wet mosslands, subspecies masseyi started to emerge later than P. argus argus in Southern England. Tutt mentions that on the mosses there was an abundance of Ornithopus perpusillus - Birds - foot ; although the foodplant of masseyi remains unknown. Even if the Victorian and later collectors could have found the larvae they would have not been able to breed this butterfly because it was not then known that Plebejus Argus has such a close assocation with Ants. Recently, detailed studies in the UK have found out here that Plebejus argus is more dependant on Ants ( Formicidae) through its entire larvae and pupae stages than any other British butterfly.
Left. Plebejus argus masseyi male verso specimen captured by C.F. Johnson during July 1918 at Witherslack Moss. OUMNH collections. Right Female masseyi specimen captured by E.J. Nurse during July 1918 at Witherslack Moss. OUMNH collections.
I had almost finished studying the cabinet drawer of masseyi in the museum when I noticed three specimens in the top left hand corner had been taken at a different locality, Holker Moss in Lancashire by a J. J. Lister. When Lister had discovered masseyi at Holker Moss in Lancashire during 1918, he found that here the females differed in some small degree to those females in the wetland colonies to the south and gave an interesting account in the ' Transactions of the Entomological Sociey of London for 1919. Holker Moss lies some 16 kms north of Witherslack moss near the estuarine part of the River Leven in North Lancashire, which is now also included in Cumbria. The two mosses are separated by high ground known as the Cartmell Fells. Indeed, until I read Lister's account I was not sure exactly where Witherslack Moss was in relation to the village of the same name. As limestone hills commence just north of the village I knew it was somewhere in the low-lying ground to the south. Witherslack Moss does not seem to appear on any maps that I have seen and as all the surviving fragments of other mosses are today sometimes now known as the Witherslack Mosses. I felt that it was important to locate the exact site of Witherslack Moss where subspecies masseyi was originally discovered . Lister records that the main masseyi site at Witherslack Moss was situated about a mile- 1.6km south of the village between the River Winster and the old road from Witherslack to Grange on the coast. To the east of the road lies the fragmented Meathrop Moss, which is now a local nature reserve and still has important populations of the northern and midland specialty Coenonympha tullia ssp davus .
Two female specimens of masseyi taken by J.J. Lister at Holker Moss during July 1919. OUMNH collections.
Lister found that in the females of masseyi from Holker Moss the blue scales were mainly confined to inner areas of the forewings and that the blue areas were much greater in those of the females from the Westmoreland mosses lying near the River Kent. This indicates that Lister has found masseyi on other mosses in the old county of Westmoreland other than at its prime locality at Witherslack. Lister mentions in his account that he had examined and compared 83 females in his collection from the River Kent mosses and 40 females from Holker Moss.
J.J. Lister certainly was a very enthusiastic collector who gave us valuable information on plebejus argus masseyi. Joseph Jackson Lister ( 1857 -1927 ) was born at Leytonstone in London, later he went to Cambridge University where he became a senior lecturer in Animal Morphology. In 1887-1888 he was chosen as the naturalist for the voyage of HMS Egeria to Christmas Island in the Indian Ocean where he discovered a number of new species. He has a Palm, Orchid and Gecko named in his honour. The ship then went on to survey Australia. He wrote a book, the Natural History of Christmas Island in 1888.
I have read that Plebegus argus masseyi finally because extinct around 1942 ( Thomas 1999). If indeed masseyi survived until that date, it must have been very rare by then. Radcliffe (2002) mentions that on several occasions he had been told that the last population of masseyi disappeared in a fire. There is a population of Plebejus argus in the Nature reserve at Prees Heath in Shropshire in the West Midlands which a number of people have referred to as subspecies masseyi. The habitat at Prees Heath is typical lowland heathland not wet mossland. The females in the Prees Heath are a mixture of the typical lowland argus with brown wings and those that have blue scaling, where on the forwings it is confined to the inner areas. There was also once another population of Plebejus argus at Delamere Forest in Cheshire which has also become extinct ; here the females were similar to those at Prees Heath. There was a mosaic of habitats at Delamere from heathland to mosses and it is not cetain which of these the population of Plebejus argus inhabited. While the population at the Shropshire site is most interesting, it sadly does not seem to be the extinct subspecies masseyi of the northern mossland sites. masseyi certainly was collected in large numbers and there must have been heavy pressure on its population. The Derby arms - Inn in the village of Witherslack where Lister and many other entomologists stayed and made it there base for their field excursions, was also the meeting place of local entomological field excursions. See the image below of one such entomological meeting at the Witherslack Derby Arms in 1904. When Lister and other collectors were enoying their days during 1918-1919 on the mosses , they probably did not know that a bill had been passed in London to drain Witherslack, Holker and some of the other mosses in the surrounding area. In the ensuing years both Holker and Witherslack mosses were indeed drained. Holker Moss became agricultural land and Witherslack moss was planted with a plantation of cash crops of conifers. So in the end it was habitat destruction by drainage and perhaps a disastrous fire and not collectors which saw the sad extinction of the charming little masseyi in its unique habitat. Only those little bright jewels in collections are a reminder of what we have sadly lost.
Entomological field meeting at the Derby Arms, Witherslack during 1904. When I stayed at the inn two years ago, the original photograph of this image was still hanging on the bar wall.
Holker Moss is now farmland. Sheep grazing the site.
