SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e1f97893c4604dedc7f8d240df18b800ba6f14162a9533bb518f47127815e7ac' 
  AND token = 'a6nz0Bwbt2qOhZxXj+JepE5fZ9ihVbJu9woCw9jNuKU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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