SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8d5edd010522455accce0c3c65585eb9b8715d0f63ef858fd1d22d495aad4d4f' 
  AND token = 'VNrZ6rQxfcLS79KbNCDGxLLzJwUVyFsGwHgW0L6TzuI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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