SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ba358ff00fe2fb40e753ca3fabaafa000ed98afc63eb57eb8d8b0714cd996a4b' 
  AND token = 'P9DPNZqwvvvWLqfbgsRHx7Lr6lK8ozeqYckYUkiIzcE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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