SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '19efd3e32747a55692c4d66e80f423009348af0a1cf70dfd04a845149156db19' 
  AND token = 'ui7/o6EwRmcCiDuTDmzpmuTGiloA7UF6wemDDsXRpX4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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