Compare

Muelleria terrestris has linear-elliptic valves with a larger central area, but without a central gibbous margin. Muelleria agnellus is larger and lacks a central gibbous margin. Muelleria tetonensis is larger and linear-elliptic with parallel margins. Muelleria spauldingiae is greater than 10 µm wide and lacks a central gibbous margin.

LM scalebar = 10 µm
Muelleria gibbula LM6 Muelleria gibbula LM1 Muelleria gibbula LM5 Muelleria gibbula LM4 Muelleria gibbula LM7 Muelleria gibbula LM3 Muelleria gibbula LM2
Length Range
21.3-40.1 µm
Width Range
6.8-9.6 µm
Striae in 10 µm
18-22 at the valve center, 22-26 at the ends

Muelleria agnellus

Bahls 2014

Muelleria agnellus LM1 Muelleria agnellus LM2 Muelleria agnellus LM3 Muelleria agnellus LM4 Muelleria agnellus LM5 Muelleria agnellus LM6 Muelleria agnellus LM7
Length Range
26.9-59.6 µm
Width Range
9.5-12.3 µm
Striae in 10 µm
13-18 at valve center, 20-24 at the apices

Muelleria spauldingiae

Bahls 2014

Muelleria spauldingiae LM1 Muelleria spauldingiae LM2 Muelleria spauldingiae LM3 Muelleria spauldingiae LM4 Muelleria spauldingiae LM5 Muelleria spauldingiae LM6 Muelleria spauldingiae LM7
Length Range
28.8-66.2 µm
Width Range
11.7-15.0 µm
Striae in 10 µm
14-17 at valve center, 18-21 at the apices

Muelleria tetonensis

Bahls 2014

Muelleria tetonensis LM1 Muelleria tetonensis LM2 Muelleria tetonensis LM3 Muelleria tetonensis LM4 Muelleria tetonensis LM5 Muelleria tetonensis LM6 Muelleria tetonensis LM7
Length Range
27.2-52.6 µm
Width Range
8.6-11.7 µm
Striae in 10 µm
16-20 at valve center, 20-24 at the apices

Also compare to

Muelleria terrestris

(J.B.Petersen) S.A.Spauld. and Stoermer 1997