SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da069f91f382f89ef7a6bd37b62c2e99ce40eb7df025b1504381c6e38f477095' 
  AND token = '/6dTaLGOSEYogXvKrF8bxAa9DLzI1QK4O3KN7fb8SxY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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