SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '92ea97870242cae2d1e6a822d2ccb1d2a7cc2a6bd8d208559e9cbba8302bd1d6' 
  AND token = 'flpeFOE3oGHo9Hnoo1NcsrJtjT5I1BN1fsJp4bhLTYY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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