SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '071393c85601703b1f77debdea606625cb4b7785a03a398c32e27d3946ccf812' 
  AND token = 'nmHxOaB1IFOWkdcxt61dAmV//D5YDuaWjAd+N2afyr8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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