SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5b7c176e691fc03886a8b38e456f9a9b75411a6bb49394c4b08a1438db8f827a' 
  AND token = 'kuGkdPcKeMuQZYuGqQueMIphcfcaj9wJGZg0bzoSKXU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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