SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d6b300c038c4bae1c9943302611100f199c16073bf7779cb8b6c356acb5e2ad' 
  AND token = 'E9Dr4Xd6RTGCghIeeJPsTKunV8ictRzLJxL+xVXlbi8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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