SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f7db2464cac4c8b92cd82feff0d6e98c9824348ab6e1658ee5d0da11be89752d' 
  AND token = 'kWEDR6Wmw0J7YGU5Xti9waNmuRdOfVQD50CaxQD0QDk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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