SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2fb25535c6d7ef6255ec6f90af317d8f034a45b7d301665f64df3ab488ab37ee' 
  AND token = 'UVLgjaONeBzOo8JDvd7XB+LBtKq3/UqcliDbobX9I4w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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