SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64a5c33c817b9ed847ca7125e0093fd87dbaffc7f39460b203fca557f876739d' 
  AND token = 'rDBGrei4FnxfdBwJpn2x2JZc4vAxr/oK5VYLHIqSTHY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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