SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee56cf1ea1421da7852a62efee0cfa17845d0bf9d4d559579f5cf46bc5b8fb60' 
  AND token = 'OUBaKsj9qUSze8OcmNqhbH/M+vHI+WJCHJXKAjt1vUU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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