SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '249abda0c4ffa4fb3a86246412054a5d7407998881e9f1eb2a99c57e52606fe1' 
  AND token = 'wvaJX9HXQkCI56E/ng5YlLwH4YnKMgKa5kQhx3PgZwU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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