SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fe9d12d229e86e96881191a1993dc19776a0c3d804cd751d2476300f8e81e529' 
  AND token = 'YsYgFUsmq1a52mJVOSdjK/fzgVKzX3h3rq+XhRvVhYM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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