SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a069de463625deee4821ffd23f5dab1ebbb35ff870e29d64c92e210cde885784' 
  AND token = 'R5XOCxHhuBkg8rSThy7yri9bNvPHlFGNA3+BiDVmEv0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}