SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '15d2069e7706fb00f158664fc6b823d97873fd24e4ba42d7d4fc5084655bc685' 
  AND token = '5sP7CHeSQ+SweK0bBckjLXTmvKB4ZnwBnyzId6ue200=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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