SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '830c75e33de467cdd827fce7b2fa829e35b60eff61c98c9ac41b4f332827ed13' 
  AND token = 'uWeH4uwvZ20THPyfnMrnG11QwlrVkwLaG1SNnWvJMrM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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