SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ddb1c73594cf10902d04ad6d9af977b16e47441db9ae5a5d3ad55a597416914d' 
  AND token = 'd5RcMirdYRhbPEGa4JtIJM4T+frAV8toyu2gJBEAn7k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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