SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5f39e092aebfa0828fad377115948596e18d032c4190c119f74a6b889cb6148e' 
  AND token = 'QgeaQtOJ5nllcSDACkIxJfMF4a46oIBoU4MbJveeKj0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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