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On last year herb stems at the base of Solidago. Apothecia are sessile, 1-1.2mm with yellow marginal hairs.
Asci 8-spored, biseriate, IKI+bb, croziers(+).
Ascospores hyaline, cylindrical, OCI=1-2, measured
(11.4) 11.9 - 14.4 (15.4) × (1.9) 1.91 - 2.1 (2.4) µm
Q = (5.6) 5.8 - 7.3 (8) ; N = 19
Me = 13.4 × 2 µm ; Qe = 6.6
Paraphyses lanceolate, without VBs.
Yellow pigment from marginal hairs dissolves in KOH.

Yes, I know its purple. See this post…I think its the same thing! (And NOT infected with Nectriopsis violacea as the color is too even). https://weirdandwonderfulwildmushrooms.blogspot.com/2016/05/when-is-fuligo-septica-purple-not-very.html?showComment=1630533311320&m=1#c4868940049623093232

Also, this source suggests F. septica var. rosea…. https://www.mycosphere.org/pdf/MYCOSPHERE_8_10_17.pdf

Amphigenous on Baccharis halimifolia. More likely Puccinia baccharidis than P. pistorica, since the uredinia aren't solely hypophyllous. Urediniospores are extremely variable in shape and size. I'll be trying to rear the Mycodiplosis larvae from the later photos.

Measurements
Urediniospores
(25–)27–43(–51)×22–32 μm; Q=1.01–2.03
Urediniospores in type description
34–44×21–31 μm

Images
Slides in LPCB
1,2: Erumpent uredinia
3,4: Urediniospores
5-7: Urediniospores and paraphyses at various levels of development
8: Urediniospores in uredinium, some with broken stalks attached
9-15: Habit with bonus Mycodiplosis larvae
16-18: Intact uredinia

Not sure what to think of this; growing on Ilex vomitoria. I thought the spots might be aphid secretions until I checked the microscopy. The raised spots on the leaf don't seem to penetrate the leaf tissues deeply, and
they grow on both surfaces. They are composed mostly of tiny club-shaped conidia/microconidia(?). The conidia are around 7 × 1 μm.

Images
Slides in LPCB (last in KOH), scale bars 10 μm.
1: Habit
2: Partially dyed conidial mass near stomata
3: Spaced conidia
4-8: Habit
9: Maybe unrelated structure

Hypophyllous on Ulmus crassifolia. Could also be P. guttata, though older literature suggests that this would be the species of Phyllactinia on Ulmus.
From what I can tell, the specific name is derived from the shape of the conidia, none of which I could find. Will keep an eye out for more descriptive literature (preferably not in German this time). Large enough that I could remove each chasmothecium individually with a razor.

Measurements
Ascospores
Difficult to find with only two mature chasmothecia, about:
25 × 18 μm
Chasmothecia
214– 248 μm

Images
Slides in LPCB, scale bars 100 μm for images 2 and 7, 10 μm otherwise.
1: Habit
2: Chasmothecium and appendages
3,4: Penicillate cells
5,6: Ascospores, presumably
7: Additional chasmothecium

Likely the same species as this observation.
A few differences:
1) This Erysiphe sp. is growing on the upper side of the leaf
2) This host is Ulmus crassifolia rather than U. americana

The two specimens don't differ greatly in microscopy, though I did find conidia in this observation, which I did not in the previous.

Measurements
Ascospores
23–30 × 12–14.5 μm
Chasmothecia
110–132 μm
Conidia
35.5–44.5 × (13.6–)16–17 μm

Images
Slides in LPCB; scale bars all 10 μm, but 100 μm in image 3.
1,2: Ephiphyllous habit
3: Chasmothecia
4: Chasmothecia appendages
5: Chasmothecium
6: Immature chasmothecium
7,8: Ascospores
9-11: Conidia

Epiphyllous on Quercus virginiana. Keys most closely to C. dentatus, but lacks the black boundary that I would expect.

Measurements
Asci
(68–)91–113 × 7.7–9.4 μm
Ascospores
50–65(–77) × 1–1.6 μm

Images
Slides in KOH, scale bars 10 μm.
1-4: Habit
5-7: Asci
8: Immature ascus
9: Paraphyses
10: Ascospores
11: Crystalized minerals in apothecium

On Ligustrum leaves. All slides in water, with a few using Lactophenol Cotton Blue while searching for any fungal symbionts. Scale bars 10 μm, 100 μm in image 14.

Measurements
Zoospores (or gametes?)
6.65 × 6.33 μm
Zoosporangia
250 × 180 μm

Images
1: Epiphyllous habit
2-4: Zoospores
5: Sporangiophore (while using LPCB)
6: Zoosporangia
7,8: Sporangiophores
9,10: Thallus
11,12: Gametangium?
13: Red pigment in setae
14: Low magnification, full view
15,16: Habit

Hypophyllous on Solidago. Urediniospores seem significantly too small to call this Coleosporium solidaginis, measuring 15–29 × 13–19 μm, whereas they are cited in literature as closer to 23–36 × 15–24 μm. Possibly C. delicatulum, but I can find no descriptions of the uredinial stage. Scale bar 10 μm.

I've found similar specimens twice before, but have never collected one for microscopy. Both teleomorphic and anamorphic forms present, growing on fallen oak. Asci are consistently 8-spored and cylindrical. Ascospore measurements are consistent with descriptions of Stilbocrea macrostoma.

Measurements
Ascospores: (8.6–)10.2–12.1(–13.5) × 5–6.2 μm
Asci: 72–97 × 5.2–7 μm

Images
All slides in Melzer's, scale bars 100 μm for images 2,6,7; 10 μm for all others
1: Habit - teleomorph (pycnidia) and anamorph (Stilbella-like pins) stalks
2: Conidioma
3-5: Asci and ascospores
6-9: Condiomata and microconidia(?)
10-18: Habit

Not too familiar with Hirsutella/Ophiocordyceps anamorphs, but seems to fit. Likely the same species group that is currently epizootic in Oncometopia and Homalodisca; on O. orbona.

Images
Scale bars 10 μm, slides in LPCB
1-6: Mycelium on host and Solidago stem
7: Spent phialides
8: Early conidia
9: Developed conidium and phialide
10: Developing conidia and phialides
11: Spent phialides and hyphae
12: Habit

Keys out to Rhytidhysteron guaraniticum on two separate keys, can't find much information on the species apart from that however. At the very least exists in Paraguay.
On Citrus bark.
Mature ascocarps often exceed 2 mm in length. Width is variable with opening/closing, but closes to 0.4-1 mm.
Ascospores
23.3–33.5 × (8.4–)10.7–13.8 μm; Q: 1.94–2.92(–3.67)
Mostly 3-septate, often 1-septate, very rarely 2-septate.

Image Notes
All microscopy with 10 μm scale bars, mounted in KOH or LPCB
2: Open ascocarps revealing epithecia after sitting in water droplets for 30 minutes
4: Ascospores
5: Asci with ascospores in cross section
6: Exciple
7: Paraphysis
8: Cross section at low magnification

Amphigenous on Salix nigra leaves. Has previously been reported from S. nigra in North America.

Measurements (µm)
Ascospores as observed:
16–22.5 × 13–15.5 /1.6–2.9 wall thickness.
Ascospores in literature:
12–25 × 10–18/1·5–3.
Paraphyses width as observed:
17–19
Paraphyses width in literature:
15–24

Images
All structures in KOH, scale bars 10 µm.
1: S. nigra leaf with infection
2: Paraphyses
3: Urediniospores
4: Paraphysis
5: Teliospores
6-7: S. nigra

Hypophyllous, likely on Quercus virginiana leaf. Long, straight chasmothecial appendages with bulbous bases – characteristic of Phyllacytinia.
Species ID is difficult without Taxonomic Manual of the Erysiphales, which is a bit pricey. Phyllactinia alnicola has been reported on Q. virginiana in Texas as Microsphaera alni, though longer chasmothecial appendages might be expected for that species.
Ascospores
Range: 34.5–39.5 μm × (16.8–)17.5–21.5 μm; 1.62–2.23 μm/μm
Average: 36.61 μm × 19.77 μm; 1.86 μm/μm
Asci
Average: ~55 μm × 45 μm
Conidia
Range: (46–)48–51(–52.7) μm × (15.7–)18–24 μm; 2–2.6(–3.3) μm/μm
Average: 49.44 μm × 20.61 μm; 2.45 μm/μm
Chasmothecia
Diameter Range: 174–224 μm
Average: 203 μm
Appendage Length Range: 263–321 μm
Average: 299 μm
App. Length/Diameter Range: 1.32–1.65 μm/μm
Average: 1.48 μm/μm

Images
Scale bars 10 μm unless otherwise specified. All mounted in either LPCB or Melzer's.
1: Chasmothecia and appendages; top left and bottom right scale bars 100 μm
2-4: Habitus with appendages visible

1. Ascospores and ascus
2. Conidioma and conidia
3. Penicillate structures
4. Overzealous squash
5. Hypha and appressorium(?)
6. Sterigma-like strucutre from penicillate hyphae
7. Appressorium (?)
8. Underside of leaf.
9. More habitus.

Urediniospores 22–28.5 × 15–18.5 μm, highly verrucose with hyaline walls ~1.5 μm thick. On Rubus sp.
Images:
1: Habitus
2: Stalked urediniospores (referred to as spores from now on)
3: Verrucose surface of spores visible in air bubble
4: Germ pores?
5: Hyphae and spores
6: Spores and paraphyses?
7: Broken stalks on spores
8: Single spore
9: Hyphae, spores
10: Full structure, scale bar at 100 μm
11: Bonus Mycodiplosis larva
12-14: Habitus

All microscopy in Melzer's, scale bars 10 μm apart from picture 10.