SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '07999f0a8a99f8d5c326f2c77c1b84cb3d76e141e502d226003b254a32ff58b2' 
  AND token = 'W4wjuD/iqPHezvkP1NXteK7s4w7Skf+BuHvgJ1lNUt4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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