SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5bdd4b628bf2c55337ef127ccc06fbf86634b20660a890bd28d71e9127a622b2' 
  AND token = 'YAY80uHU5qn9Ikh2NYNC9LJrh08Buml/ZhQGyXjPOI8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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