SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e1a65735c5f1d3faa2e76fd401be41ca3d56eb5bd6584aeb5207c22a08362bac' 
  AND token = 'tcftc8S2oidN6lDPRtluMUfkWh2E8deuqB3iEjKkDA0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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