Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6a690dcf3337bcac38d6d47e4c6a45b7ad2ac8bf41cedf9f5d80f8ac5262e1c2' 
  AND token = 'S86kM9gkQfuCCWym+tZi56NlmGyij8EXcW1QKfTLepc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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