SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd4480c4157a854a8f04fe5beb04e0019b243631541d2756223d65039ed7875d8' 
  AND token = 'X9ScJYg0Hn4JWDWf1qXj9govaA9Tz5cmXuGmXZKB7MI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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