SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2270a6004ab931d2b442414837d1323e54acb34b40416e82c5ccf4bd02f2f9b9' 
  AND token = 'LUMXhoDZBsrD6OFVJ/jXkuHvjF2KT6wQqGIHAjV8Bio=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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