SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '542f2a194a0b830f894a8907583c4735168dc43285d68242e7de08c05b8818f1' 
  AND token = 'OOKUS808R5WD4KzOMFnXM8YolcLl8G9bH16YaOveHYs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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