SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f0d334d862eb96a45500469cb5b8c5774ed5c34daa2fb08aba19b6160645eca' 
  AND token = 'C+swt/ZmGDfSs6wRgyGpvhx/RdFZTTQ6ET1hMpGh8oE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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