SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b89709b91b048422aaae6eccec7ae2577b2868c82fc911af03348cb0ce09bfa7' 
  AND token = 'ynwEaytWRJvAFR8QNLB8uAvkR+66SuQMSeKbmeb30LM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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