SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9a59372e2cb8b4bd08563e1f3aa0bfc820c3a3f09855f15b81fd1cd2c27cd93e' 
  AND token = 'uhbRZwqioJUBzBg/3Zfdr7ArnaKpHI6frgwsDWCxej4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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