SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48cb0794677c6965ba855e300913d6c6ab4c1ea4e54adbcafefd80c3cf447dc1' 
  AND token = 'XT/0CTkMFNuhEAK/RSpxdb5w5wO/mEjPeAVTKXP/2ao=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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