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Megachile apicalis - The Hidden Bee - A Cautionary Tale

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  • Sam Droege
    All: I am wrapping up a paper on the bees of Baltimore Harbor, from collections made last year. I reported on this a while back. One of the interesting things
    Message 1 of 7 , Jul 31, 2011
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      All:

      I am wrapping up a paper on the bees of Baltimore Harbor, from collections made last year.  I reported on this a while back. One of the interesting things was the discovering of large numbers of rarely collected introduced species.

      My editor, Gene Scarpulla, noted that Megachile apicalis did not appear to be on the Maryland list of species compiled by John Ascher.  I checked, and he was right.  This as far as we know, is the first recording of the species in the state.  I had assumed that I had recorded it as  had found it to be not uncommon on its pollen plant / weed Centaurea in NJ, PA, and NY, but in my region Centaurea is much less common and I am often out of state during that time of year (plus it is hot out!).

      In doing a little research I found the there were some very early records of this species in the region and put together the paragraph below:


      Megachile apicalis Spinola is a non-native species from the Mediterranean region.  While widespread in the West it is relatively unrecorded in the East with almost all recent records confined to the New York, New Jersey, Pennsylvania region.  Most likely this is due to its pollen specialization on Centaurea species and a general lack of collecting.  Interesting, the first recording of this species with good locality information that we are aware of was from 1931 in Rosemont, Fairfax County, Virginia on Centaurea cyanus (University of California, Riverside Entomological Research Museum).  Interestingly, Mitchell (1962) mentions a female without locality information but dated 1882.  Thus this species likely has remained regionally undetected for         long periods of time (Mitchell speculated that this species was possibly an unsuccessful introduction) giving one pause as to what else we may be failing to observe in our nearby bee fauna.  


      As far as I can tell Spotted Knapweed (C. stoebe) is the dominant introduced knapweed that lines roadways and railroad lines in the Mid-Atlantic and has also been on the continent since the 1880s.  Does anyone know if it has become more common recently in the East?

      It is also worth noting that almost all records of Lithurgus chyrsurus are from collections off Knapweed patches.  

      Wouldn't it be interesting (and easy) to do a survey of Knapweed patches in the East..;..

      Look at the figure below...  Knapweeds are declared noxious weeds throughout the continent...where are the M. apicalis records?  

      Surely there are recent Canadian records....

      Also this shows how easy it is to overlook species of bees and one has to wonder about the real status of, in particular, the loosestrife specialists if nobody is looking on loosestrife plants....

      sam

      Illustration of the DL records for M. apicalis



      OK, you Midwesterners....go out and collect off all your stands of Knapweed

      sam

                                                             
      Sam Droege  sdroege@...                      
      w 301-497-5840 h 301-390-7759 fax 301-497-5624
      USGS Patuxent Wildlife Research Center
      BARC-EAST, BLDG 308, RM 124 10300 Balt. Ave., Beltsville, MD  20705
      Http://www.pwrc.usgs.gov

      Carmen Possum

      The nox was lit by lux of Luna,
      And 'twas a nox most opportuna
      To catch a possum or a coona;
      For nix was scattered o'er this mundus,
      A shallow nix, et non profundus.
      On sic a nox with canis unus,
      Two boys went out to hunt for coonus.  
      The corpus of this bonus canis
      Was full as long as octo span is,
      But brevior legs had canis never
      Quam had hic dog; et bonus clever,
      Some used to say, in stultum jocum
      Quod a field was too small locum
      For sic a dog to make a turnus
      Circum self from stem to sternus.
      Unis canis, duo puer,
      Nunquam braver, nunquam truer,
      Quam hoc trio nunquam fuit,
      If there was I never knew it.
      This bonus dog had one bad habit,
      Amabat much to tree a rabbit,
      Amabat plus to chase a rattus,
      Amabat bene tree a cattus.
      But on this nixy moonlight night
      This old canis did just right.
      Nunquam treed a starving rattus,
      Nunquam chased a starving cattus.
      But sucurrit on, intentus
      On the track and on the scentus,
      Till he trees a possum strongum,
      In a hollow trunkum longum.
      Loud he barked in horrid bellum,
      Seemed on terra vehit pellum.
      Quickly ran the duo puer
      Mors of possum to secure.
      Quam venerit, one began
      To chop away like quisque man.
      Soon the axe went through the truncum
      Soon he hit it all kerchunkum;
      Combat deepens, on ye braves!
      Canis, pueri et staves;
      As his powers non longius tarry,
      Possum potest, non pugnare.
      On the nix his corpus lieth.
      Down to Hades spirit flieth,
      Joyful pueri, canis bonus,
      Think him dead as any stonus.
      Now they seek their pater's domo,
      Feeling proud as any homo,
      Knowing, certe, they will blossom
      Into heroes, when with possum
      They arrive, narrabunt story,
      Lenus blood et plenior glory.
      Pompey, David, Samson, Caesar,
      Cyrus, Black Hawk, Shalmanezer!
      Tell me where est now the gloria,
      Where the honors of victoria?
      Nunc a domum narrent story,
      Plenus sanguine, tragic, gory.
      Pater praiseth, likewise mater,
      Wonders greatly younger frater.
      Possum leave they on the mundus,
      Go themselves to sleep profundus,
      Somniunt possums slain in battle,
      Strong as ursae, large as cattle.
      When nox gives way to lux of morning,
      Albam terram much adorning,
      Up they jump to see the varmen,
      Of the which this is the carmen.
      Lo! possum est resurrectum!
      Ecce pueri dejectum,
      Ne relinquit track behind him,
      Et the pueri never find him.
      Cruel possum! bestia vilest,
      How the pueros thou beguilest!
      Pueri think non plus of Caesar,
      Go ad Orcum, Shalmanezer,
      Take your laurels, cum the honor,
      Since ista possum is a goner!

      Author Unknown
    • John S. Ascher
      Sam: Thanks for this interesting posting. Megachile apicalis is also on my mind this weekend, as I observed a probable female yesterday with a full pollen load
      Message 2 of 7 , Jul 31, 2011
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        Sam:

        Thanks for this interesting posting.

        Megachile apicalis is also on my mind this weekend, as I observed a
        probable female yesterday with a full pollen load and obtained this
        photograph:

        http://pick14.pick.uga.edu/mp/20p?see=I_JSA1834&res=640

        I did not collect a voucher as it was on federal parkland at Floyd Bennett
        Field. If anyone has an opinion about my probable M. apicalis ID or can
        confirm ID of the host plant please email me directly.

        Regarding the map pasted in Sam's email, please note that the actual known
        distribution of M. apicalis is considerably narrower than depicted,
        because the map in question includes state record centroids from my
        AMNH_BEES literature database in addition to georeferenced specimen
        records. To display only georeferenced specimen records, simply click on
        "Customize this Map" and then set "Map points using" to "coordinates" (not
        "both" coordinates and gazetteer which is the default setting). In this
        case it was not ideal to make the default map (optimized for speed) as
        this, taken at face value, gives a misleading impression of the bee's
        actual occurrence. I hope all advanced users of DL can consistently convey
        the need to use customized maps for any sophisticated purpose (such as
        precisely plotting confirmed localities for a bee species) and to realize
        that data are owned in all cases by particular data providers with
        differing standards of identification and georeferencing quality. One
        cannot expect an optimal result when accepting all records in the global
        repository GBIF (very keen to add hundreds of millions of records in the
        absence of any adequate methods to error-check or update these), mixing
        literature reports with precise specimen records, and generating maps with
        the most convenient option as opposed to taking advantage of advanced
        mapping options. In all cases it is necessary to credit individual data
        providers rather than simply citing "Discover Life" as a catch-all source
        as was done in recent species distribution modeling papers on Anthidium
        manicatum and on South American Peponapis.

        When the map of M. apicalis is customized to show display only specimen
        records, these cluster rather tightly along the NYC-to-DC corridor
        (exluding the outlying Elmira, NY record), in cismontane California (esp.
        in and around the Central Valley), and a limited area of NE OR and SE WA.

        Sam, please double check your Elmira, NY record. This is of considerable
        interest, as in my experience the only Eutricharaea found in the greater
        Fingerlakes Region of NY is rotundata. There are no apicalis records from
        Ithaca and vicinity despite very extensive collecting. Nearly all NY
        records of apicalis seem to be from NYC.

        "widespread in the West"

        This has not been demonstrated, at least based on specimen records
        displayed on DL. It is certainly widespread and very abundant in CA and
        also well known from NE OR and SW WA, but it's occurrence elsewhere in the
        west is not well documented.

        Terry, please verify if there is a valid Utah record (I have a state
        record but no specimen records are mapping on DL yet)?

        "Surely there are recent Canadian records.... "

        This seems to be pure speculation. I am aware of a "Canada" record but
        don't have any details of this and cannot confirm it. It would useful to
        confirm even one Canadian record of any age attributable to a province.

        "the real status of, in particular, the loosestrife specialists if nobody
        is looking on loosestrife plants...."

        By this do you mean yellow or purple loosestrife. There is an important
        difference! Both have specialist bees at least where native.

        If you mean yellow loosestrife, bee specialists have certainly looked for
        Macropis on Lysimachia in recent decades but are finding them only
        locally. By contrast, in the late 19th and early 20th centuries this genus
        was found by many collectors (including general entomologists) from many
        collectors in the vicinity of cities such as NYC, Boston, and DC. Most
        recent records are by specialist bee collectors from relatively few sites.
        Macropis have genuinely become hard to find but still exist at the most
        favorable remaining localities most of which are distant from cities.

        The case of Megachile apicalis, with its surprisingly limited confirmed
        distribution when maps are made and interpreted precisely, illustrates why
        it is important to map records with caution (being sure to screen out
        imprecise gazetteer centroids and suspicious georeferenced points from
        certain data providers) when considering the details of bee distributions.
        It also shows why it is is better to precisely delimit and even enumerate
        species ranges in preference to making misleading generalizations such as
        "widespread in the West" (as in Sam's draft text) or "e. U.S." (Cane
        2001). Our exotic and native bees are both more and less widespread in
        time and space than we might assume, and we must take care to use
        available resources optimally if we want to understand past and present
        distributional patterns. It's great to be concise when citing species
        ranges, but not at the expense of accuracy, especially in the case of
        species with dynamic and poorly documented ranges such as M. apicalis.

        John
      • Laurence Packer
        Cory has recorded it from Canada for the first time - from southern BC.  His Megachile revision has been revised to take into considering an increasing number
        Message 3 of 7 , Jul 31, 2011
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          Cory has recorded it from Canada for the first time - from southern BC.  His Megachile revision has been revised to take into considering an increasing number of new finds, including that one.

          cheers

          laurence

          --- On Sun, 7/31/11, John S. Ascher <ascher@...> wrote:

          From: John S. Ascher <ascher@...>
          Subject: Re: [beemonitoring] Megachile apicalis - The Hidden Bee - A Cautionary Tale
          To: "Sam Droege" <sdroege@...>
          Cc: beemonitoring@yahoogroups.com
          Received: Sunday, July 31, 2011, 12:36 PM

           



          Sam:

          Thanks for this interesting posting.

          Megachile apicalis is also on my mind this weekend, as I observed a
          probable female yesterday with a full pollen load and obtained this
          photograph:

          http://pick14.pick.uga.edu/mp/20p?see=I_JSA1834&res=640

          I did not collect a voucher as it was on federal parkland at Floyd Bennett
          Field. If anyone has an opinion about my probable M. apicalis ID or can
          confirm ID of the host plant please email me directly.

          Regarding the map pasted in Sam's email, please note that the actual known
          distribution of M. apicalis is considerably narrower than depicted,
          because the map in question includes state record centroids from my
          AMNH_BEES literature database in addition to georeferenced specimen
          records. To display only georeferenced specimen records, simply click on
          "Customize this Map" and then set "Map points using" to "coordinates" (not
          "both" coordinates and gazetteer which is the default setting). In this
          case it was not ideal to make the default map (optimized for speed) as
          this, taken at face value, gives a misleading impression of the bee's
          actual occurrence. I hope all advanced users of DL can consistently convey
          the need to use customized maps for any sophisticated purpose (such as
          precisely plotting confirmed localities for a bee species) and to realize
          that data are owned in all cases by particular data providers with
          differing standards of identification and georeferencing quality. One
          cannot expect an optimal result when accepting all records in the global
          repository GBIF (very keen to add hundreds of millions of records in the
          absence of any adequate methods to error-check or update these), mixing
          literature reports with precise specimen records, and generating maps with
          the most convenient option as opposed to taking advantage of advanced
          mapping options. In all cases it is necessary to credit individual data
          providers rather than simply citing "Discover Life" as a catch-all source
          as was done in recent species distribution modeling papers on Anthidium
          manicatum and on South American Peponapis.

          When the map of M. apicalis is customized to show display only specimen
          records, these cluster rather tightly along the NYC-to-DC corridor
          (exluding the outlying Elmira, NY record), in cismontane California (esp.
          in and around the Central Valley), and a limited area of NE OR and SE WA.

          Sam, please double check your Elmira, NY record. This is of considerable
          interest, as in my experience the only Eutricharaea found in the greater
          Fingerlakes Region of NY is rotundata. There are no apicalis records from
          Ithaca and vicinity despite very extensive collecting. Nearly all NY
          records of apicalis seem to be from NYC.

          "widespread in the West"

          This has not been demonstrated, at least based on specimen records
          displayed on DL. It is certainly widespread and very abundant in CA and
          also well known from NE OR and SW WA, but it's occurrence elsewhere in the
          west is not well documented.

          Terry, please verify if there is a valid Utah record (I have a state
          record but no specimen records are mapping on DL yet)?

          "Surely there are recent Canadian records.... "

          This seems to be pure speculation. I am aware of a "Canada" record but
          don't have any details of this and cannot confirm it. It would useful to
          confirm even one Canadian record of any age attributable to a province.

          "the real status of, in particular, the loosestrife specialists if nobody
          is looking on loosestrife plants...."

          By this do you mean yellow or purple loosestrife. There is an important
          difference! Both have specialist bees at least where native.

          If you mean yellow loosestrife, bee specialists have certainly looked for
          Macropis on Lysimachia in recent decades but are finding them only
          locally. By contrast, in the late 19th and early 20th centuries this genus
          was found by many collectors (including general entomologists) from many
          collectors in the vicinity of cities such as NYC, Boston, and DC. Most
          recent records are by specialist bee collectors from relatively few sites.
          Macropis have genuinely become hard to find but still exist at the most
          favorable remaining localities most of which are distant from cities.

          The case of Megachile apicalis, with its surprisingly limited confirmed
          distribution when maps are made and interpreted precisely, illustrates why
          it is important to map records with caution (being sure to screen out
          imprecise gazetteer centroids and suspicious georeferenced points from
          certain data providers) when considering the details of bee distributions.
          It also shows why it is is better to precisely delimit and even enumerate
          species ranges in preference to making misleading generalizations such as
          "widespread in the West" (as in Sam's draft text) or "e. U.S." (Cane
          2001). Our exotic and native bees are both more and less widespread in
          time and space than we might assume, and we must take care to use
          available resources optimally if we want to understand past and present
          distributional patterns. It's great to be concise when citing species
          ranges, but not at the expense of accuracy, especially in the case of
          species with dynamic and poorly documented ranges such as M. apicalis.

          John

        • Sam Droege
          John et al. Below is the map without the state centroids for the species Hey John: The Elmyra records are good ones. I had 14 specimens, about half caught in
          Message 4 of 7 , Jul 31, 2011
          • 0 Attachment
            John et al.

            Below is the map without the state centroids for the species






            Hey John:

            The Elmyra records are good ones.  I had 14 specimens, about half caught in bowls and half caught in nets on knapweed along the rr tracks that go through town.

            sam

            The murmuring of bees has ceased;
            But murmuring of some
            Posterior, prophetic,
            Has simultaneous come,--

            The lower metres of the year,
            When nature's laugh is done,--
            The Revelations of the book
            Whose Genesis is June.
               -Emily Dickinson



            From:"John S. Ascher" <ascher@...>
            To:"Sam Droege" <sdroege@...>
            Cc:beemonitoring@yahoogroups.com
            Date:07/31/2011 12:36 PM
            Subject:Re: [beemonitoring] Megachile apicalis - The Hidden Bee - A      Cautionary Tale
            Sent by:beemonitoring@yahoogroups.com





             



            Sam:

            Thanks for this interesting posting.

            Megachile apicalis is also on my mind this weekend, as I observed a
            probable female yesterday with a full pollen load and obtained this
            photograph:

            http://pick14.pick.uga.edu/mp/20p?see=I_JSA1834&res=640

            I did not collect a voucher as it was on federal parkland at Floyd Bennett
            Field. If anyone has an opinion about my probable M. apicalis ID or can
            confirm ID of the host plant please email me directly.

            Regarding the map pasted in Sam's email, please note that the actual known
            distribution of M. apicalis is considerably narrower than depicted,
            because the map in question includes state record centroids from my
            AMNH_BEES literature database in addition to georeferenced specimen
            records. To display only georeferenced specimen records, simply click on
            "Customize this Map" and then set "Map points using" to "coordinates" (not
            "both" coordinates and gazetteer which is the default setting). In this
            case it was not ideal to make the default map (optimized for speed) as
            this, taken at face value, gives a misleading impression of the bee's
            actual occurrence. I hope all advanced users of DL can consistently convey
            the need to use customized maps for any sophisticated purpose (such as
            precisely plotting confirmed localities for a bee species) and to realize
            that data are owned in all cases by particular data providers with
            differing standards of identification and georeferencing quality. One
            cannot expect an optimal result when accepting all records in the global
            repository GBIF (very keen to add hundreds of millions of records in the
            absence of any adequate methods to error-check or update these), mixing
            literature reports with precise specimen records, and generating maps with
            the most convenient option as opposed to taking advantage of advanced
            mapping options. In all cases it is necessary to credit individual data
            providers rather than simply citing "Discover Life" as a catch-all source
            as was done in recent species distribution modeling papers on Anthidium
            manicatum and on South American Peponapis.

            When the map of M. apicalis is customized to show display only specimen
            records, these cluster rather tightly along the NYC-to-DC corridor
            (exluding the outlying Elmira, NY record), in cismontane California (esp.
            in and around the Central Valley), and a limited area of NE OR and SE WA.

            Sam, please double check your Elmira, NY record. This is of considerable
            interest, as in my experience the only Eutricharaea found in the greater
            Fingerlakes Region of NY is rotundata. There are no apicalis records from
            Ithaca and vicinity despite very extensive collecting. Nearly all NY
            records of apicalis seem to be from NYC.

            "widespread in the West"

            This has not been demonstrated, at least based on specimen records
            displayed on DL. It is certainly widespread and very abundant in CA and
            also well known from NE OR and SW WA, but it's occurrence elsewhere in the
            west is not well documented.

            Terry, please verify if there is a valid Utah record (I have a state
            record but no specimen records are mapping on DL yet)?

            "Surely there are recent Canadian records.... "

            This seems to be pure speculation. I am aware of a "Canada" record but
            don't have any details of this and cannot confirm it. It would useful to
            confirm even one Canadian record of any age attributable to a province.

            "the real status of, in particular, the loosestrife specialists if nobody
            is looking on loosestrife plants...."

            By this do you mean yellow or purple loosestrife. There is an important
            difference! Both have specialist bees at least where native.

            If you mean yellow loosestrife, bee specialists have certainly looked for
            Macropis on Lysimachia in recent decades but are finding them only
            locally. By contrast, in the late 19th and early 20th centuries this genus
            was found by many collectors (including general entomologists) from many
            collectors in the vicinity of cities such as NYC, Boston, and DC. Most
            recent records are by specialist bee collectors from relatively few sites.
            Macropis have genuinely become hard to find but still exist at the most
            favorable remaining localities most of which are distant from cities.

            The case of Megachile apicalis, with its surprisingly limited confirmed
            distribution when maps are made and interpreted precisely, illustrates why
            it is important to map records with caution (being sure to screen out
            imprecise gazetteer centroids and suspicious georeferenced points from
            certain data providers) when considering the details of bee distributions.
            It also shows why it is is better to precisely delimit and even enumerate
            species ranges in preference to making misleading generalizations such as
            "widespread in the West" (as in Sam's draft text) or "e. U.S." (Cane
            2001). Our exotic and native bees are both more and less widespread in
            time and space than we might assume, and we must take care to use
            available resources optimally if we want to understand past and present
            distributional patterns. It's great to be concise when citing species
            ranges, but not at the expense of accuracy, especially in the case of
            species with dynamic and poorly documented ranges such as M. apicalis.

            John



          • Laurence Packer
            This is fabulous - it seems clear that we are talking about two independent origins. If anyone can get a sample of these bees for me from either side of the
            Message 5 of 7 , Jul 31, 2011
            • 0 Attachment
              This is fabulous - it seems clear that we are talking about two independent origins.
              If anyone can get a sample of these bees for me from either side of the continent (the larger the sample the better - but ten would be useful) I would be most grateful.
              Let me know if any of you might be able to do this.

              best wishes

              laurence

              --- On Sun, 7/31/11, Sam Droege <sdroege@...> wrote:

              From: Sam Droege <sdroege@...>
              Subject: Re: [beemonitoring] Megachile apicalis - The Hidden Bee - A Cautionary Tale
              To: beemonitoring@yahoogroups.com
              Received: Sunday, July 31, 2011, 5:56 PM

               

              John et al.

              Below is the map without the state centroids for the species






              Hey John:

              The Elmyra records are good ones.  I had 14 specimens, about half caught in bowls and half caught in nets on knapweed along the rr tracks that go through town.

              sam

              The murmuring of bees has ceased;
              But murmuring of some
              Posterior, prophetic,
              Has simultaneous come,--

              The lower metres of the year,
              When nature's laugh is done,--
              The Revelations of the book
              Whose Genesis is June.
                 -Emily Dickinson



              From:"John S. Ascher" <ascher@...>
              To:"Sam Droege" <sdroege@...>
              Cc:beemonitoring@yahoogroups.com
              Date:07/31/2011 12:36 PM
              Subject:Re: [beemonitoring] Megachile apicalis - The Hidden Bee - A      Cautionary Tale
              Sent by:beemonitoring@yahoogroups.com





               



              Sam:

              Thanks for this interesting posting.

              Megachile apicalis is also on my mind this weekend, as I observed a
              probable female yesterday with a full pollen load and obtained this
              photograph:

              http://pick14.pick.uga.edu/mp/20p?see=I_JSA1834&res=640

              I did not collect a voucher as it was on federal parkland at Floyd Bennett
              Field. If anyone has an opinion about my probable M. apicalis ID or can
              confirm ID of the host plant please email me directly.

              Regarding the map pasted in Sam's email, please note that the actual known
              distribution of M. apicalis is considerably narrower than depicted,
              because the map in question includes state record centroids from my
              AMNH_BEES literature database in addition to georeferenced specimen
              records. To display only georeferenced specimen records, simply click on
              "Customize this Map" and then set "Map points using" to "coordinates" (not
              "both" coordinates and gazetteer which is the default setting). In this
              case it was not ideal to make the default map (optimized for speed) as
              this, taken at face value, gives a misleading impression of the bee's
              actual occurrence. I hope all advanced users of DL can consistently convey
              the need to use customized maps for any sophisticated purpose (such as
              precisely plotting confirmed localities for a bee species) and to realize
              that data are owned in all cases by particular data providers with
              differing standards of identification and georeferencing quality. One
              cannot expect an optimal result when accepting all records in the global
              repository GBIF (very keen to add hundreds of millions of records in the
              absence of any adequate methods to error-check or update these), mixing
              literature reports with precise specimen records, and generating maps with
              the most convenient option as opposed to taking advantage of advanced
              mapping options. In all cases it is necessary to credit individual data
              providers rather than simply citing "Discover Life" as a catch-all source
              as was done in recent species distribution modeling papers on Anthidium
              manicatum and on South American Peponapis.

              When the map of M. apicalis is customized to show display only specimen
              records, these cluster rather tightly along the NYC-to-DC corridor
              (exluding the outlying Elmira, NY record), in cismontane California (esp.
              in and around the Central Valley), and a limited area of NE OR and SE WA.

              Sam, please double check your Elmira, NY record. This is of considerable
              interest, as in my experience the only Eutricharaea found in the greater
              Fingerlakes Region of NY is rotundata. There are no apicalis records from
              Ithaca and vicinity despite very extensive collecting. Nearly all NY
              records of apicalis seem to be from NYC.

              "widespread in the West"

              This has not been demonstrated, at least based on specimen records
              displayed on DL. It is certainly widespread and very abundant in CA and
              also well known from NE OR and SW WA, but it's occurrence elsewhere in the
              west is not well documented.

              Terry, please verify if there is a valid Utah record (I have a state
              record but no specimen records are mapping on DL yet)?

              "Surely there are recent Canadian records.... "

              This seems to be pure speculation. I am aware of a "Canada" record but
              don't have any details of this and cannot confirm it. It would useful to
              confirm even one Canadian record of any age attributable to a province.

              "the real status of, in particular, the loosestrife specialists if nobody
              is looking on loosestrife plants...."

              By this do you mean yellow or purple loosestrife. There is an important
              difference! Both have specialist bees at least where native.

              If you mean yellow loosestrife, bee specialists have certainly looked for
              Macropis on Lysimachia in recent decades but are finding them only
              locally. By contrast, in the late 19th and early 20th centuries this genus
              was found by many collectors (including general entomologists) from many
              collectors in the vicinity of cities such as NYC, Boston, and DC. Most
              recent records are by specialist bee collectors from relatively few sites.
              Macropis have genuinely become hard to find but still exist at the most
              favorable remaining localities most of which are distant from cities.

              The case of Megachile apicalis, with its surprisingly limited confirmed
              distribution when maps are made and interpreted precisely, illustrates why
              it is important to map records with caution (being sure to screen out
              imprecise gazetteer centroids and suspicious georeferenced points from
              certain data providers) when considering the details of bee distributions.
              It also shows why it is is better to precisely delimit and even enumerate
              species ranges in preference to making misleading generalizations such as
              "widespread in the West" (as in Sam's draft text) or "e. U.S." (Cane
              2001). Our exotic and native bees are both more and less widespread in
              time and space than we might assume, and we must take care to use
              available resources optimally if we want to understand past and present
              distributional patterns. It's great to be concise when citing species
              ranges, but not at the expense of accuracy, especially in the case of
              species with dynamic and poorly documented ranges such as M. apicalis.

              John



            • Griswold, Terry
              John, Sam, We have records of Megachile apicalis from CA, and from golf courses in OR & southern WA. We have no field caught records from UT or anywhere else
              Message 6 of 7 , Aug 3, 2011
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                John, Sam,

                 

                We have records of Megachile apicalis from CA, and from golf courses in OR & southern WA.  We have no field caught records from UT or anywhere else in the Great Basin & Colorado Plateau.  The suggestion of UT might have come from specimens in our collection that are labeled “Logan Greenhouse” and were flown in caged experiments.  These are not being served on GBIF.

                 

                terry

                 

                Terry Griswold

                USDA ARS Bee Biology & Systematics Laboratory
                Utah State University
                Logan, UT 84322-5310
                USA

                435.797.2526

                435.797.0461 Fax

                 

                From: beemonitoring@yahoogroups.com [mailto:beemonitoring@yahoogroups.com] On Behalf Of John S. Ascher
                Sent: Sunday, July 31, 2011 10:36 AM
                To: Sam Droege
                Cc: beemonitoring@yahoogroups.com
                Subject: Re: [beemonitoring] Megachile apicalis - The Hidden Bee - A Cautionary Tale

                 

                 



                Sam:

                Thanks for this interesting posting.

                Megachile apicalis is also on my mind this weekend, as I observed a
                probable female yesterday with a full pollen load and obtained this
                photograph:

                http://pick14.pick.uga.edu/mp/20p?see=I_JSA1834&res=640

                I did not collect a voucher as it was on federal parkland at Floyd Bennett
                Field. If anyone has an opinion about my probable M. apicalis ID or can
                confirm ID of the host plant please email me directly.

                Regarding the map pasted in Sam's email, please note that the actual known
                distribution of M. apicalis is considerably narrower than depicted,
                because the map in question includes state record centroids from my
                AMNH_BEES literature database in addition to georeferenced specimen
                records. To display only georeferenced specimen records, simply click on
                "Customize this Map" and then set "Map points using" to "coordinates" (not
                "both" coordinates and gazetteer which is the default setting). In this
                case it was not ideal to make the default map (optimized for speed) as
                this, taken at face value, gives a misleading impression of the bee's
                actual occurrence. I hope all advanced users of DL can consistently convey
                the need to use customized maps for any sophisticated purpose (such as
                precisely plotting confirmed localities for a bee species) and to realize
                that data are owned in all cases by particular data providers with
                differing standards of identification and georeferencing quality. One
                cannot expect an optimal result when accepting all records in the global
                repository GBIF (very keen to add hundreds of millions of records in the
                absence of any adequate methods to error-check or update these), mixing
                literature reports with precise specimen records, and generating maps with
                the most convenient option as opposed to taking advantage of advanced
                mapping options. In all cases it is necessary to credit individual data
                providers rather than simply citing "Discover Life" as a catch-all source
                as was done in recent species distribution modeling papers on Anthidium
                manicatum and on South American Peponapis.

                When the map of M. apicalis is customized to show display only specimen
                records, these cluster rather tightly along the NYC-to-DC corridor
                (exluding the outlying Elmira, NY record), in cismontane California (esp.
                in and around the Central Valley), and a limited area of NE OR and SE WA.

                Sam, please double check your Elmira, NY record. This is of considerable
                interest, as in my experience the only Eutricharaea found in the greater
                Fingerlakes Region of NY is rotundata. There are no apicalis records from
                Ithaca and vicinity despite very extensive collecting. Nearly all NY
                records of apicalis seem to be from NYC.

                "widespread in the West"

                This has not been demonstrated, at least based on specimen records
                displayed on DL. It is certainly widespread and very abundant in CA and
                also well known from NE OR and SW WA, but it's occurrence elsewhere in the
                west is not well documented.

                Terry, please verify if there is a valid Utah record (I have a state
                record but no specimen records are mapping on DL yet)?

                "Surely there are recent Canadian records.... "

                This seems to be pure speculation. I am aware of a "Canada" record but
                don't have any details of this and cannot confirm it. It would useful to
                confirm even one Canadian record of any age attributable to a province.

                "the real status of, in particular, the loosestrife specialists if nobody
                is looking on loosestrife plants...."

                By this do you mean yellow or purple loosestrife. There is an important
                difference! Both have specialist bees at least where native.

                If you mean yellow loosestrife, bee specialists have certainly looked for
                Macropis on Lysimachia in recent decades but are finding them only
                locally. By contrast, in the late 19th and early 20th centuries this genus
                was found by many collectors (including general entomologists) from many
                collectors in the vicinity of cities such as NYC, Boston, and DC. Most
                recent records are by specialist bee collectors from relatively few sites.
                Macropis have genuinely become hard to find but still exist at the most
                favorable remaining localities most of which are distant from cities.

                The case of Megachile apicalis, with its surprisingly limited confirmed
                distribution when maps are made and interpreted precisely, illustrates why
                it is important to map records with caution (being sure to screen out
                imprecise gazetteer centroids and suspicious georeferenced points from
                certain data providers) when considering the details of bee distributions.
                It also shows why it is is better to precisely delimit and even enumerate
                species ranges in preference to making misleading generalizations such as
                "widespread in the West" (as in Sam's draft text) or "e. U.S." (Cane
                2001). Our exotic and native bees are both more and less widespread in
                time and space than we might assume, and we must take care to use
                available resources optimally if we want to understand past and present
                distributional patterns. It's great to be concise when citing species
                ranges, but not at the expense of accuracy, especially in the case of
                species with dynamic and poorly documented ranges such as M. apicalis.

                John

              • Doug Yanega
                ... For this reason, we do not database locality data for any reared or inspector-intercepted specimens *unless* we know the locality of the source population
                Message 7 of 7 , Aug 3, 2011
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                  Terry wrote:

                  >We have records of Megachile apicalis from CA, and from golf courses
                  >in OR & southern WA. We have no field caught records from UT or
                  >anywhere else in the Great Basin & Colorado Plateau. The suggestion
                  >of UT might have come from specimens in our collection that are
                  >labeled "Logan Greenhouse" and were flown in caged experiments.
                  >These are not being served on GBIF.

                  For this reason, we do not database locality data for any reared or
                  inspector-intercepted specimens *unless* we know the locality of the
                  source population (and then we database that source). There were some
                  heated arguments with my boss over this with regards to thousands of
                  specimens of exotic parasitoid wasps reared in our quarantine
                  facilities, which he wanted to database as being from Riverside,
                  creating points on distribution maps giving a place where these
                  species do not naturally occur. He thought it should be sufficient to
                  include a note somewhere in some "miscellaneous notes" field that
                  said something like "lab culture originally from Durban, South
                  Africa", but I finally convinced him with the argument that people
                  would never read those notes, and instead assume that the mapped
                  points indicated these species had escaped and established in the
                  wild here in the US, and likewise make it impossible to recognize
                  those few cases where something HAS been introduced and established
                  here - he admitted that this would be a bad thing, and capitulated.

                  Peace,
                  --

                  Doug Yanega Dept. of Entomology Entomology Research Museum
                  Univ. of California, Riverside, CA 92521-0314 skype: dyanega
                  phone: (951) 827-4315 (standard disclaimer: opinions are mine, not UCR's)
                  http://cache.ucr.edu/~heraty/yanega.html
                  "There are some enterprises in which a careful disorderliness
                  is the true method" - Herman Melville, Moby Dick, Chap. 82
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