SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd82f34357a766a148955ad5acac4e96614bc27a6a48369496c3fa104b7e9bc38' 
  AND token = 'JOnWPPQSjq7G3Dr9eCpmwh/qNbX8Uv6i3azQ3O+mtBw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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