SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '10a8a5ec69c2adc1eea92198ccdd08e9e2f69ad2cc3bafe6f06dd605bb10b90b' 
  AND token = 'DD3MMtFdYSSd/fqZMpkFYXba/NzBfM0NyqDGcw0UmLU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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