SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c05351127ed3015ccace4e3ce9335bab1422791546967a1e4b5fc2c5c47482fb' 
  AND token = 'y/zMsRDZEi1eYr2zDlvZvee5pzEdULDslPEoKufdZTU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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