SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '897dd42d7a3586ef7e929900207a8dbb2804b98c57c9b8d3481128b6fd1cfab1' 
  AND token = 'Hdzsl/bnNeMmrHE1DttRNwUAqSEcbmhbs2dO1dXW/nc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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