SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f0d3fc467df048ef0f96dd1bac0dc44ecef3b50dcccf7897b8dae4755da66206' 
  AND token = 'TVC4nWB5LzDJ36Xpxwmd/5UUwlmShdzUSoWdGd3YrCY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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