SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d47f83657cd372f5e92d85a0430ac53f9a5d74f26b2e1c17e21a92dc907ece0' 
  AND token = 'LSz2h6YR4sZbIOAc6/5U3wgJ/sp8+NlUi6DVLM1uSJw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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