SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f19ef0ed230df9a2085f919fedd85d8f0359a0d119a1ed66cde2f8b8aeda223' 
  AND token = '9FwWtChsKmfinQ0iZaqp6IiS8e9t76huM9WwQ7yt+v8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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