SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8cf8aa0a961be57a0ec448864e6a664c1a6c72dc29e92dbaba0ce14f9371050a' 
  AND token = 'kOyb5a8OroSviioLmJE8zCbgZw6SaPhjKKmXZ3GVCA4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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