SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9af97bf031ec6180224aeb706fade3ce556fb577c5254b2024ff28759db9bd4c' 
  AND token = '831/LdgtSW9St5GsvSIrVcwAK/s9LmqA9G/iA+7ZR0c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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