SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c2d38bceb805eb60f514a50111a3b56ad4de80838a259dfb52de450fcfdad200' 
  AND token = 'Blx53fkRiToRAvXt6p6naNTtcEKVa9Q5xVpJS/UmfTk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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