SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bb0064f03d435732268b1d0943cfc5aa95a35560faf6a184c00d0de7587f3b32' 
  AND token = 'l5+aqIOYTMDtQ9zUiZDzpzXqiw1BJWVXq+VCejAT+UI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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