SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f4f1144d2c9245c8f67ae396901c4a43cea3ead1452825cf9fdae806f27dba1c' 
  AND token = 'T6fHC0gHdycNpE+kh4aMu22zr/XD5cp24kvsbp7sN9s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00008

JSON explain

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