SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ad5cc02a8f9d8a7d5f9c3bdaea06d57341d28a5d266df4b24d36d4fd41679b3b' 
  AND token = 'xNyqYmnrsWmGdlPKr/hKkpdw/od1YIAxpAY/ctFszn4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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