SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c89312a3f74c36d551344903044b493d03b4381a4498afd32fe09215adf68460' 
  AND token = 'LhFsFOuBWYz71FpM5r30AjZu8SGiFAaIboqqtEpNaEo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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