SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '02d2237876bcef68459e798b330694751211d687bd250c94191047c1ffeb3e9c' 
  AND token = 'YWclXMRH0A5O7+PDjJ6OEEUlPn/RdkLQrlYnusEa3P8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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