SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d27a37db4dbebc607d8d3745fe1bfb4a1b9afafa00cc79c4c7573794413efa7' 
  AND token = 'LFGCiasbk2m7tOoYhy9Y6O1LHgCcyGgeTLi6auhFTXk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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