SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ce7f0f1b9b01ec28c6b1c809223c704d1e68fb1488b3c2af673f2807a6413b73' 
  AND token = 'qOhQZoR7X426A9ZWtbViZd8Jd/T2EthQPoSd443+zHs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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