SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6a6d4017a886b03207555d8d290015b963b196e49d1c8d575c697fc68fd0f9fa' 
  AND token = 'orheIsioCXsm4BGffvJAxgjvACX+tsCgMmuiN4FuUwk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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