SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9de6c0f897558a96d02b3f071e943297387c5344ae6c1b58529fc645f132e14e' 
  AND token = 'GsTe+ZrloN2ANVXn++ZSSyX1LYhb0IDXj9KBgjiQ1/Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00060

JSON explain

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