SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '117dd55b4d54603f99c674f9ad0c753107a21f8bec85a607ff80217dbf45a92e' 
  AND token = '4G1dYY90dXW/+NicU7Q3m4hEpfe8/UNRELwRHt41TzU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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