SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '57dcb55bde33be98c7759c328646e1bbe53e14f42fef07a06c3c50b15d74ae86' 
  AND token = 'cp19tyb7jvekGskygnZm5prQNfa3HRCYfU+lR6Z/iqM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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