SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '985af24df803c99b78b572a09e23906a766827275fb26c4b507215d84882339f' 
  AND token = 'pqY9KULq8UxjYi2B3PuxkPY0IbGU88EPmUXl23FO2VQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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