SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4386cbe8d661d0f889048f64a5a8ccd3e6757f48630d30e4ce8121ccd280a07a' 
  AND token = 'F+82MakzUyk/xRxS1XGmKO3Y1ra9ZP/ifHDTDNo/I0Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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