SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f95a9bc5911f61fac56e8b18f5d749e47585a3639cd5057fb86b329c6e133354' 
  AND token = '7CzHMsHIO0QeF5mkI58JAPBEVsh27y0GBlBca0R3j+E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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