SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a4b1e2f41d78d0e62d2aec1641bf57179cf30bc3b3e03e3969d93e102969e573' 
  AND token = 'gKzMX4/8YYbYHBf1gGjOTVurJsUUG2L9SG2WF2O2IRw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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