SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b72f9e06960346c171e03dd1a8adf1aac3278c2cc940cb773d4561a6695306ff' 
  AND token = 'fY+/AIK7B6UcqfPPhkgNwjjnVU9a2pbLNw29GHnsUSA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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