SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '795199508e9b10486d031657bd87bcc0e395629abbce6d430acf28623bf93785' 
  AND token = 'lzbM26a9UNMkYS0p0mDKqNNZqPHvXJu/iucO9ekkJD8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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