SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '569fdd925d2322c53e2d26171f61c4761204735a34fbc133ae871671e54ac5a0' 
  AND token = '9DEB7MP+otMakDpfP37zRXWeHW4R/68dwdGKaYFTS/4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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