SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '52e90d73cfd08977a1a83f5552ca5e161b61a92cb6731a9a77fb05e70f89e606' 
  AND token = 'o0zyYlDFJohSt+4sOpfW1jLuvuJen6Y9MXBxyUh0k/Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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