SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9c91b94cd46a3c8ced6ca732bba7dc0d8935e18031ed03a191ff05330d27996e' 
  AND token = 'SWSkj0HNd5QACBWIBZIMZP7o1ZCokaqWEtX410wV/5U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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