Beethoven Piano trios: numbers

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I didn't realise before that Beethoven's "first" works are piano trios, though apparently his Opus 1 isn't really!

Below is a list of Beethoven's piano trios, extracted from a well known source.

Opus 1: Three Piano Trios (1795)
No. 1: Piano Trio No. 1 in E-flat major
No. 2: Piano Trio No. 2 in G major
No. 3: Piano Trio No. 3 in C minor
Opus 11: Piano Trio [No. 4](?) in B-flat major ("Gassenhauer") (1797)
Opus 44: Variations on an original theme in E-flat major
Opus 70: Two Piano Trios (1808)
No. 1: Piano Trio [No. 5](?) in D major, "Ghost"
No. 2: Piano Trio [No. 6](?) in E-flat major
Opus 97: Piano Trio [No. 7](?) in B-flat major ("Archduke") (1811)
Opus 121a: Kakadu Variations, for Piano Trio (Variations on "Ich bin der Schneider Kakadu") (1803)

The numbering is uncertain, as the Op 11 trio started off as a trio with wind instruments - but with optional scoring.
Currently I'm reminding myself of Op 70 No 2 - which doesn't have a well known name. http://open.spotify.com/track/4eco9j6ezsz3NWz8cIPG3S

The numbering of the Beethoven piano trios is a bit confusing.
The trios opus 1 are the very first works which Beethoven considered to be worthy of getting an opus number, but these aren't his very first published works either. That's a variation set on a March by Dressler, WoO 63, from 1784 iirc.

A complication with the trio numbering is the fact that the trio opus 11, is for clarinet or violin, cello and piano.
Therefore it is omitted in the numbering.
Hence:
3 trios op.1 = trios nos 1-3
2 trios opus 70 = trios 4 & 5
Archduke trio op.97 = trio 6

But the list is not complete. It should be:
Hess 48: Movement for piano trio in E-flat (1790) (a complete movt among the first extensive sketches for the opus 1 trios)
WoO 38 Piano trio in E-flat (1792; an omitted trio likely originally meant for opus 1)
Opus 1: Three Piano Trios (published 1795)
*No. 1: Piano Trio No. 1 in E-flat major
*No. 2: Piano Trio No. 2 in G major
*No. 3: Piano Trio No. 3 in C minor
Opus 11: Piano Trio in B-flat major ("Gassenhauer") (1797)
Opus 36a: Piano trio after Symphony no.2 (Beethoven's own transcription)
Opus 38: Piano trio after the Septet opus 20 for clarinet or violin, cello and piano (Beethoven's own transcription)
Opus 44: Variations on an original theme in E-flat major (1800)
Opus 70: Two Piano Trios (1808)
*No. 1: Piano Trio No. 4 in D major, "Ghost"
*No. 2: Piano Trio No. 5 in E-flat major
Opus 97: Piano Trio No. 6 in B-flat major ("Archduke") (1811)
WoO 39 Piano trio in B-flat in one movement for Bettina von Brentano (1812)
Opus 121a: Kakadu Variations, for Piano Trio (Variations on "Ich bin der Schneider Kakadu") (1803)

Opus 63: piano trio after string quintet opus 4 / wind octet op.103. this work might be an arrangement by Beethoven, but there are severe doubts regarding its authorship and as such considered to be spurious

WoO Anh.3 Rondo for piano trio in D. Beethoven's authorship doubtful, but so far neither confirmed or firmly to be rejected.

Philips' Beaux Arts recordings consist of all piano trios except for op.63 and Anh.3
Philips originally numbered the trios from 1 to 11, confusingly opus 44 being trio no.10 and op.121a no.11