SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b22ead881db098982fcd853d38e576f753386ae5f55623edbe9af75c0c84359b' 
  AND token = 'AaOXPgFnBWORmi6rNVWIf+v3BDdwZ2c3xkGfE7+h4XQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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