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My first attempt at diatoms cleaning.

Three specimens observed, from the same sample of my previous observation https://www.inaturalist.org/observations/141202070 taken on 2022-11-05.

Stria density: 7-8 per 10 μm (center), 10-11 (extremities).
Puncta density: 11 per 10 μm.
Length 213-225 µm, width 41-44 µm.

Stigmata visible near the central nodule.

According to Diatoms of Europe vol.3 by Kurt Krammer, 2002, it looks like Cymbella peraspera:
“Valves moderately to distinctly dorsiventral, dorsal margin rather evenly arched, ventral margin with a slightly gibbous central portion. Valve ends not protracted and broadly rounded. Length (130)154-320 µm, breadth 44-52 µm, maximal length/breadth ratio about 6. Axial area moderately wide, linear, widening at mid-valve to form a shallow central area, about ¼ to nearly ⅓ of the valve breadth. Raphe slightly lateral, tape ring near proximal and distal ends, becoming filiform near the proximal and the distal ends. Proximal raphe ends with moderately large roundish central pores which are slightly ventrally deflected; terminal fissures sickle-shaped and dorsally bent. Striae throughout radiate. Puncta distinctly and more or less roundish in focus high and low. A large number of stigmata on the ventral side of the central nodule, in focus low differently shaped from the puncta, commonly distant from the middle ventral striae. Striae 5-8/10 µm, becoming up to 10/10 µm near the extremities. Puncta 7-10(11) in 10 µm.”

Male found drowned on 26.vi.2007. Genitalia missing, sex assumed as male as there is no ovipositor and there are six visible sternites, seven tergites and tylloids on antenna. Total length 14 mm. Body partly covered with pale brown hairs. HEAD: Head not broader than thorax. Antenna with the flagellum black, widened in the middle, narrowed apically. Flagellum with 44 segments, 5th to 15th with oval tyloids; F1 and F2 more than two times as long as wide (=21/10 at 45 x, both). Genal carina meeting the hypostomal carina at least at a short distance from the base of the mandible. Clypeus flat or scarcely convex, with no longitudinal wrinkles, apex truncated. Mandibles bidentate, not twisted nor sickle-shaped. Face and frons with the inner orbits ivory, the upper mark extending to a mid distance from the orbit to the posterior ocellus. Clypeus margins marked with ivory. MESOSOMA: Transverse groove of pronotum without any interruption. Scutellum convex, with a transverse dumbbell shaped ivory spot in the middle. Propodeum: Propodeum with a distinct division into dorsal and posterior surfaces. Basal groove of propodeum deep. Area basalis with a median tubercle or carina projecting into the basal groove. Area superomedia transverse, subcordiform (19/40 mm long, 27/40 mm wide), rounded anteriorly, more smooth than the adjacent areas. Lateral and posterior edges of area dentipara with raised keels, apices of area dentiparae forming sharp raised corners. Lateral carina of the petiolar area longer than the costula. Spiracles of propodeum elongate, many times longer than wide. Marked with ivory are the middle of the pronatal collar, the hind angles of pronotum and the subalar prominence. Mesoscutum covered with pale brown hairs, mostly gone when cleaning it. METASOMA: Black, red in the space between the segments. T1: Basal third of petiole subquadrate in section, about as high as broad. Postpetiole with lateral and central areas differentiated; central area (=18/45 mm) wider than lateral areas (12/45 mm); central area irregularly and finely striate or punctate; lateral areas punctuated. T2: Tergite 2 base rugose-striated, with some isolated punctures. Gastrocoeli clearly defined, fairly deeply impressed, approximately triangular, with distinct thyridia. Thyridia narrower (=19/45 mm) than interspace between them (=32/45 mm). LEGS: Fore metatarsi expanded externally in an apical tooth. Middle femur not excised ventrally in the apical third. Claws not pectinated. All coxae, trochanteres and trochantellus black. Fore femora, fore tibia and mid femora light red or orange; hind femora dark red, broadly infuscated at both ends; mid and hind tibia, fore, mid and hind tarsi dark brown. REMARKS: Previously wrongly determined as Coelichneumon impressor, but the shape of the propodeum is not so roundly slanted as the dentiparal angles are forming sharp corners; also the postpetiole sculpture is different. Determination following Perkins (1959, 1960) from subfamily to species (genus Barichneumon sensu Perkins, as area basalis has a median tubercle pointing anteriorly; species as Barichneumon monostagon). The extension of the ivory mark between the compound eye and the posterior ocelli is more than stated (“mark extending at most to a third the distance from the orbit to the posterior ocellus”). Determination from family to subtribe also following Tereshkin 2009 and from subtribe to genus following Tereshkin 2004. Berthomieu 1894, Ceballos 1924, Meier 1968, Heinrich 1977, Rasnitsyn 1981 were also studied.

The rest of the day and evening we spent around Madera Canyon in the Coronado National Forest. It was a really wonderful location! :)

Still working on the ID's for these...

Check out the journal entry for lots of better photos of many of these same species:
http://www.inaturalist.org/journal/sambiology/11501-southeast-arizona-inaturalist-is-a-community