Plant–insect interactions from the Middle Triassic (Ladinian) Forcella da Cians/Ritberg Flora, of the Agordo Formation near Wengen/La Valle, St. Veit-Seewald, within the Fernazza Formation, and St. Veit-Innerkohlbach, near Prags/Braies, within the Wengen/La Valle Formation in the northern Dolomites.

<p><b>A</b>: The pteridosperm <i>Ptilozamites sandbergeri</i> showing abundant DT80 galls along the leaf surface. Specimen PAL-1516 (St. Veit-Innerkohlbach). <b>B</b>: Successive, end-to-end oviposition marks (DT175) on a <i>Ptilozamites sandbergeri</i> rachial midvein, showing a series of four lesions (arrows). Specimen PAL-202 (Forcela da Cians). <b>C</b>: Oviposition (DT76) on the rachial midvein of another specimen of <i>Ptilozamites sandbergeri</i>. Specimen PAL-11 (Forcela da Cians). <b>D</b>: A pinnule of <i>Marattiopsis</i> sp., showing development of a leaf mine (DT222) adjacent to the primary vein. Specimen PAL-231 (St. Veit-Innerkohlbach). <b>E</b>: Enlargement of midvein-centered leaf mine (DT222) in the rectangular template in (D). Arrow shows the mine frass trail along the midrib. <b>F</b>: The fern <i>Cladophlebis leuthardtii</i>, with a small example of cuspate margin feeding (DT12). Specimen PAL-73 (St. Veit-Innerkohlbach). <b>G</b>: Foliar gall (DT32) on a fourth specimen of <i>Ptilozamites sandbergeri</i>. Specimen PAL-18 (Forcela da Cians). All specimens are reposited in the Museum of Nature South Tyrol (MNS), in Bolzano, Italy. Scale bars: striped = 1 mm; solid = 10 mm.</p

Stratigraphic and geographic context of localities that provide plant–insect interaction data for the Permian–Triassic sequence from the Dolomites Region in northeastern Italy.

<p>Geologic scale is after [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0165205#pone.0165205.ref076" target="_blank">76</a>]; grey dots designate localities discussed in this report black dots refer to principal towns and villages; and lines delimit major roads.</p

Plant–insect interactions from the Middle Triassic (Anisian) Kühwiesenkopf/Monte Prà della Vacca Flora, of the Dont Formation at Kühwiesenkopf/Monte Prà della Vacca in the northeastern Dolomites.

<p><b>A</b>: The lycopod <i>Lycopia dezancheri</i>, showing an example of slot feeding (DT08). Specimen PAL-7603. <b>B</b>: A stem of the sphenopsid <i>Neocalamites asperrimus</i>, with a cluster of oviposition scars (DT159). Specimen PAL-11. <b>C</b>: Enlargement of a series of linear rows of oviposition scars in (B). <b>D</b>: Incised margin feeding (DT15) on an isolated pinnule of the cycadophyte <i>Bjuvia</i> sp., indicated by black arrow. Specimen PAL-1599. <b>E</b>: A leaf of the cycadophyte <i>Bjuvia</i> sp. with examples of hole feeding (DT01, DT02), indicated by arrows. Specimen PAL-294. <b>F</b>: The cycadophyte <i>Bjuvia dolomitica</i>, showing four examples of slot feeding (DT08). Specimen PAL-2147. <b>G</b>: Enlargement of slot feeding (DT08) indicated by rectangular template in (F), showing underlying matrix. <b>H</b>: Surface feeding (DT82) on both sides on the basal portion on a cycadophyte leaf of <i>Bjuvia</i> sp. Specimen PAL-729. <b>I</b>: Two miniscule galls (DT80), indicated by black arrows on the cycadophyte <i>Bjuvia</i> sp. Specimen PAL-655. <b>J</b>: Successive pinnules of the cycadophyte <i>Bjuvia</i> sp., showing several small galls (DT80). <b>K</b>: Enlargement of gall at the lower-left template in (J). <b>L</b>: The broadleaved conifer <i>Voltzia</i> sp., displaying a scale mark (DT77), circumscribed by rectangular template. Specimen PAL-1108. <b>M</b>: Enlargement of scale mark at (L). <b>N</b>: An undetermined cycadophyte, with an oviposition scar (DT76) along a rachis. Specimen PAL-11. <b>O</b>: Detail of the oviposition scar, at the juncture of the blade and rachis. <b>P</b>: The cycadophyte <i>Ptilozamites heeri</i>, with a DT32 gall. All specimens are reposited in the Museum of Nature South Tyrol (MNS), in Bolzano, Italy. Scale bars: striped = 1 mm; solid = 10 mm.</p

Plant–insect interactions from the Middle Triassic (Ladinian) Monte Agnello Flora, of the Vulcanites near Predazzo in the central Dolomites.

<p><b>A</b>: The cycadophyte <i>Nilssonia neuberi</i>, displaying cuspate margin feeding (DT12), indicated by the arrow. Specimen MGP-191-6A. <b>B</b>: Another example of <i>Nilssonia neuberi</i>, exhibiting an example of a scale mark DT77. Specimen MGP-194-72A. <b>C</b>: The cycadophyte <i>Bjuvia</i> sp., showing examples of surface feeding (DT31) and margin feeding (DT15) along the right margin of the blade. <b>D</b>: Enlargement of polylobate surface feeding (DT31) from the upper template and trenched margin feeding (DT15) from the template in (C). <b>E</b>: A second example of <i>Bjuvia</i> sp., showing successive examples of surface feeding (DT29) on the three lower pinnules. Specimen MGP-196-43. <b>F</b>: The coniferophyte <i>Voltzia</i> sp., showing a gall indicated in the rectangular template. Specimen MGP-171-81. <b>G</b>: Enlargement of the beaked gall (DT121) from the template in (G), showing structure very similar to that described [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0165205#pone.0165205.ref019" target="_blank">19</a>] for a walchian conifer. <b>H</b>: A <i>Phlebopteris</i> sp. pinnule displaying cuspate margin feeding (DT12) along its lower border (arrows). Specimen MPG-191-64. <b>I</b>: A <i>Phlebopteris</i> sp. pinnule exhibiting a DT106 gall along midveinal area. Specimen MPG-194-84. <b>J</b>: A <i>Phlebopteris</i> sp. pinnule with a gall at arrow (DT106) occupying the area between the midveinal axis and pinnule edge. Specimen MPG-194-83. All specimens are reposited in the Museo della Geologia di Predazzo, and the Museum of Nature South Tyrol (MNS), Italy. Scale bars: striped = 1 mm; solid = 10 mm.</p

Damage Type (DT) Occurrences on the plant hosts from the early Permian (Kungurian) to Middle Triassic (Ladinian) of northeastern Italy organized by functional feeding groups (FFGs) and subgroups and damage types (DTs).

<p>Damage Type (DT) Occurrences on the plant hosts from the early Permian (Kungurian) to Middle Triassic (Ladinian) of northeastern Italy organized by functional feeding groups (FFGs) and subgroups and damage types (DTs).</p

Quantitative distribution of plant–insect interactions Ladinian strata in northeastern Italy.

<p>Quantitative distribution of plant–insect interactions Ladinian strata in northeastern Italy.</p

Damage type (DT) diversity and generalization–specialization proportions for the four major floras examined.

<p>Damage type (DT) diversity and generalization–specialization proportions for the four major floras examined.</p

Plant–insect interactions from the Middle Triassic (Anisian) Furkelpass and related floras, of the Richthofen Formation near Olang/Valdaora in the northern Dolomites.

<p><b>A</b>: Extensive margin feeding (DT12, DT14) of pinnular foliage on the pteridosperm <i>Scytophyllum bergeri</i>, indicated by black arrows. Specimen PAL-492. <b>B</b>: The pinnular margin of <i>Scytophyllum bergeri</i> is altered along its blade by margin feeding (DT12), indicated by black arrows. Specimen PAL-523. <b>C</b>: Another pinnule of <i>Scytophyllum bergeri</i> displaying margin feeding damage (DT12, DT143). Specimen PAL-466. <b>D</b>: Pinnule of <i>Scytophyllum bergeri</i>, exhibiting single (DT12) and multiple (DT143) examples of margin feeding. Specimen PAL-513. <b>E</b>: A <i>Scytophyllum bergeri</i> pinnule displaying single and continuous margin feeding (DT12, DT143). Specimen PAL-481. <b>F</b>: Margin feeding (DT12) on the pteridosperm <i>Scytophyllum bergeri</i>. Specimen PAL-473. <b>G</b>: A frond portion of <i>Scytophyllum bergeri</i> with several pinnules, one of which displays an example of slot feeding (DT08). Specimen PAL-469. <b>H</b>: Enlargement of pinnule in the polygon at the lower-left of (G), showing slot feeding. <b>I</b>: A specimen of showing a miniscule example of oviposition (DT76) on woody tissue, indicated by a black arrow. Specimen PAL-468. <b>J</b>: A pinnular fragment of <i>Scytophyllum bergeri</i> with extensive margin feeding (DT12, DT14) one of which is illustrated at the white arrow. Specimen PAL-483. <b>K</b>: Paired piercing-and-sucking marks (DT46, DT47) indicated by black arrows, on <i>Scytophyllum bergeri</i>. Specimen PAL-491. <b>L</b>: Ovipositional damage (DT175) to <i>Scytophyllum bergeri</i>, indicated by black arrows. Specimen PAL-510. <b>M</b>: Several examples of slot feeding (DT08), indicated by arrows, on <i>Scytophyllum bergeri</i>. Specimen PAL-518. <b>N</b>: A probable leaf mine (DT41) on a pinnule of <i>Scytophyllum bergeri</i>. Leaf mine margins are indicated by a drawn, dotted line. Main mine body indicated by white arrow and possible terminus by black arrow. Specimen PAL-517. All specimens are reposited in the Museum of Nature South Tyrol (MNS), in Bolzano, Italy. Scale bars: striped = 1 mm; solid = 10 mm.</p

Plant–insect interactions from the Lopingian (Wuchiapingian) Gröden/Val Gardena Flora, of the Gröden/Val Gardena Sandstone at Bletterbach Gorge in the western Dolomites.

<p><b>A</b>: Two examples at left of margin feeding (DT12), indicated by black arrows, on a degraded pinnule of the unaffiliated plant <i>Dicranophyllum</i> sp. Specimen PAL-997. <b>B</b>: Enlargement of (A), showing margin reaction tissue. <b>C</b>: Margin feeding (DT13) on the pinnular tip of the conifer <i>Ortiseia leonardii</i>. Specimen PAL-2020. <b>D</b>: An undetermined cycadophyte, showing an oviposition mark (DT76) on rachis, encompassed by polygonal template at left. Specimen PAL-1532. <b>E</b>: Enlarged image of oviposition mark in (D). The rachial epidermal apparently is absent. <b>F</b>: the ginkgophyte <i>Sphenobaiera nutzmani</i> exhibiting margin feeding (DT12) at top (black arrow) and surface feeding (DT130) below in the rectangular template. Specimen PAL-445. <b>G</b>: A magnified version of DT130 at (F), showing consumption of surface tissues. <b>H</b>: The pteridophyte <i>Sphenopteris</i> sp. 1 pinnule showing surface feeding damage (DT30), indicated by the roughened surface. PAL-1455. <b>I</b>: A globose gall (DT153) on the stem of the conifer <i>Quadrocladus</i> sp., indicated by central bulbous tissue and radiating files of cells. Specimen PAL-1464. <b>J</b>: Indeterminate, discoidal, platysperm seed with seed predation (DT74) indicated by arrow. Specimen PAL-1088. <b>K</b>: Wood borings (DT160) on an indeterminate, debarked axis. Specimen PAL-2016. <b>L</b>: Enlargement of borings at (K), showing circular cross section and infill pattern. <b>M</b>: Foliar fascicle of the conifer <i>Pseudovoltzia liebeana</i> with one foliage element showing a bulging gall (DT33) at black arrow. Specimen PAL-859. <b>N</b>: A stem of the conifer <i>Quadrocladus</i> sp., showing eight, lenticular-shaped oviposition marks (DT175) perpendicular to the stem axis. Specimen PAL-1448. <b>O</b>: An oviposition mark (DT76) on an unknown woody axis. Specimen PAL-837. <b>P</b>: The ginkgophyte <i>Sphenobaiera</i> sp., showing two major areas of surface feeding (DT30) on the blade and petiole, indicated by black arrows and margin feeding (DT12) at white arrow. Specimen PAL-821. All specimens are reposited in the Museum of Nature South Tyrol (MNS), in Bolzano, Italy. Scale bars: striped = 0.1 mm; solid = 10 mm.</p

The insect herbivore component community of pteridosperm <i>Scytophyllum bergeri</i>, from the Middle Triassic (Anisian) Furkelpass floras of northeastern Italy.

<p>Eleven DTs are represented on this host plant, including counterclockwise from the upper left: piercing and sucking of DT46 (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0165205#pone.0165205.g007" target="_blank">Fig 7K</a>); single-egg oviposition of DT72 (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0165205#pone.0165205.g007" target="_blank">Fig 7I</a>); surface feeding of DT103 (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0165205#pone.0165205.g007" target="_blank">Fig 7M</a>), a related DT also recorded as DT82 in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0165205#pone.0165205.g009" target="_blank">Fig 9G</a>; margin feeding on pinnule apices of DT14 (Figs <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0165205#pone.0165205.g007" target="_blank">7A, 7B, 7D, 7J</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0165205#pone.0165205.g009" target="_blank">9E</a>); multiple-egg oviposition of DT175 (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0165205#pone.0165205.g007" target="_blank">Fig 7L</a>); single pinnular margin feeding of DT12 (Figs <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0165205#pone.0165205.g007" target="_blank">7F, 7J</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0165205#pone.0165205.g009" target="_blank">9E, 9F and 9I</a>); leaf mining of DT71 (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0165205#pone.0165205.g007" target="_blank">Fig 7N</a>), also shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0165205#pone.0165205.g009" target="_blank">Fig 9H</a> as DT41; continuous pinnular margin feeding of DT143 (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0165205#pone.0165205.g007" target="_blank">Fig 7C–7E</a>); galling of DT80 (not Figd); slot hole feeding of DT08 (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0165205#pone.0165205.g007" target="_blank">Fig 7G and 7H</a>); and polylobate hole feeding of DT03 (not Figd). Herbivore insect culprits for these DTs likely were ovipositing odonatans (DT72, DT175), orthopterans (DT12, DT14, DT143), thysanopterans (DT46), sternorrhynchan and heteropteran hemipterans (DT46, DT80), chresmodids (DT72, DT175) tenthredinoid sawflies (DT80, DT143) and polyphagan beetles (DT03, DT08, DT103, DT71) [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0165205#pone.0165205.ref009" target="_blank">9</a>,<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0165205#pone.0165205.ref055" target="_blank">55</a>,<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0165205#pone.0165205.ref057" target="_blank">57</a>]. Possible predators on the herbivores were odonatans, dermapterans, neuropterans, and adephagan and polyphagan beetles. Note that the herbivore feeding-guild diversity on <i>S</i>. <i>bergeri</i> is about three times of that on Late Permian <i>Pseudovoltzia liebeana</i>.</p