SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4bfc9cd3115d6e2ba157d517e53c56d17c21fab8be165a3a8ac20726075e8f7e' 
  AND token = 'TTKpLf7sz/y7tXYKggQAsaXvr4PVjIgpCwGZCsv0rkE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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