SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be07e79ecb9b72454009620bd0916575fc68d1cbdece7a229c4a0c4abecd05f4' 
  AND token = '9sQEU5Bp3dOzTiRIVdOLm2ivbaymvODGjhfwv5/laf4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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