SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6d0909efb1d2578c24404dc97a4c62f2ed16f12eabddaee98bca3aa8dc3e9769' 
  AND token = 'tHFAj/5T2jNJngQpQo1rwXU/lMlQ+OYrI6knHqOnNMg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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