SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05c76b565d6ebc646b804f294b1d92bcd8c61bdb478db8ac77d2ed0f5b2f2de9' 
  AND token = 'jRno5TUBGqYtXQoJ+41OBYOwrH+Fa3SKssy1PSbkrCg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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