Initial Statement of Beneficial Ownership (3)

FORM 3	UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES	OMB APPROVAL OMB Number: 3235-0104 Estimated average burden hours per response... 0.5
	Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940

1. Name and Address of Reporting Person ^*

ARCH CAPITAL GROUP LTD.

2. Date of Event Requiring Statement (MM/DD/YYYY) 8/24/2021

3. Issuer Name and Ticker or Trading Symbol

CALAMOS STRATEGIC TOTAL RETURN FUND [CSQ]

(Last) (First) (Middle)

100 PITTS BAY ROAD, WATERLOO HOUSE, GROUND FLOOR

4. Relationship of Reporting Person(s) to Issuer (Check all applicable)

_____ Director ___X___ 10% Owner
_____ Officer (give title below) _____ Other (specify below)

(Street)

PEMBROKE, D0 HM 08

(City) (State) (Zip)

5. If Amendment, Date Original Filed(MM/DD/YYYY)

6. Individual or Joint/Group Filing(Check Applicable Line)

___ Form filed by One Reporting Person
_X_ Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)
Series D Mandatory Redeemable Preferred Shares	280000 ⁽¹⁾	I	See footnote 1

*Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)*
1. Title of Derivate Security (Instr. 4)	2. Date Exercisable and Expiration Date (MM/DD/YYYY)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
1. Title of Derivate Security (Instr. 4)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	4. Conversion or Exercise Price of Derivative Security		6. Nature of Indirect Beneficial Ownership (Instr. 5)

Explanation of Responses:
(1)	The reported securities are owned directly by Arch Reinsurance Ltd., a wholly-owned subsidiary of Arch Capital Group Ltd.

Reporting Owners
Reporting Owner Name / Address	Relationships
Reporting Owner Name / Address	Director	10% Owner	Officer	Other
ARCH CAPITAL GROUP LTD. 100 PITTS BAY ROAD WATERLOO HOUSE, GROUND FLOOR PEMBROKE, D0 HM 08		X
ARCH REINSURANCE LTD. 100 PITTS BAY ROAD WATERLOO HOUSE, 1ST FLOOR PEMBROKE, D0 HM 08		X

Signatures
/s/ Francois Morin		10/29/2021
^**Signature of Reporting Person		Date
/s/ Tim Peckett		10/29/2021
^**Signature of Reporting Person		Date