SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '104023f512b9fc43585df6b4fffdbdbcbd16a4d11dd789cda7a972342518a00a' 
  AND token = 'ga6hX43cDqhQe6d7k8fa/zNnUx0nYvssjCHAPxqOR8o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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