SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'acdbfcc74e1ecd3b51eb0c238adb0bf8387f93f0a5e49812adf16227f6c00adb' 
  AND token = 'N8eNvjyf1DD+IKUKCQsj4j++ncbTBrTuIjFO9gOTJvI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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