SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e004840f05691283fb84fa917aee5449a3fda83269fa66da960bff1aa39ca0a2' 
  AND token = 'TIWQWUsUjyXBS0OnPC1T3SdGuyPZYPeGD8PKBkjZ9eg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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