Sandbox

SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'b9b1c2c1a1e5b2dae0e734de93fc6c5ac6dbd2cd088ed14fc3bd3d54f6e8cb20' 
  AND token = '8UOZtROEjDUkdry8yVGfbPM/UMIsfu9uZdIOt4VumtA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}