SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1e52609813b780691c79bd79dac9412ecb174a948582f59d6f3b186cd21a2a91' 
  AND token = 'sVA1+IH7N/ezFXAOCbLvaOLndAP/3XW6pjF4RnrwXBM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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