SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e40154427a9d6d68920172b7fcf7250f5c85be6fa881bfa4091f35ac547be807' 
  AND token = 'wAgs7D4EKSZdRpS36U3PS3nTlanu69AwtP4T1TUTmq8=' 
  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"
    }
  }
}