SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45b59451e6acf5d8c45eda32a3e92eb84085e5a99489279833f0fea18304b3fb' 
  AND token = 'XxIpXKK27xPLFmyrWhKPSgCrrWRzD2n1awC26NOcqCA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}