SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ed4292817e33f9b0caebe83cbc6b48f1d43bb36b1fd99244132124360250632' 
  AND token = 'EzzHDKNy5hlCeFB1HBL9vtP9kjqVpvSSil3+YmsmpC0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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