SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '70254aaf293433b021d4b64326105408e066eb815376a2ad0b3422dad9c9ede2' 
  AND token = 'TFZvWOhnYsSJ+e0yAMhgWcXgwCU+Nno2gx8ihgr44vs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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