SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e0c2479028357d4be058a6659359959ca91ddc535b94f0a340287ac86dfa4265' 
  AND token = 'gFD/lrVVAoNd4koV6PJNqZQ0WQGiViYLLXraN6kgYLY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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