SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd8fc046b7703cde912e57d5c60d6c5c4c89719d075559d7e7b93d4dde5b20336' 
  AND token = 'nZde3BWPiq0yIqRmNfV8kHI7w/aJEqTRVYSQt7wuAeI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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