SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '237cd01b361b7ffe23ff9dc4c67525bea98d3abbb5bb8de769fcadded4152caf' 
  AND token = 'VrFi/6IkoLxCmyebcI+jbACXkTWaWnf+nJ4kycaxGiE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}