SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'dd8743dd7c54d8f97a01881194a8099fa9ac504ca21f1e761f6edc41b6be85a2' 
  AND token = '79TwbHlArmwtYptppTmY9FyYaF1P1c6lV5mBEPoM6ig=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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