SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '08bb631b0ae04c85e2544e8ccb89efd13f3717660af6e7acd73418dabc7bdeb7' 
  AND token = 'K8uHEbAYDvAG7l7aHNFnHJOHLmLYtdEhbdYHBh+3g/I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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