SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aeaba3a14855ea4e651d7e68b70589d08eab11647b681ffe11a73bd7b39c3b20' 
  AND token = 'Tl3xl8bkDFyvOkw8uLEbbSgWdySLekFVv2GCIsZSIGM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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