SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '823bc35f9db0a1b18a150bdb6be3d15ff011857a11a6f59e42b3a03d8434407a' 
  AND token = 'ZOdjhbGhY1wK5RuX1c13JlquzHd/74D1Tzg1s+s9pCg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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