SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b08d7c99906506eb3833466fcb289be3a59ff54db78cf834d710217f48fd4736' 
  AND token = 'iIVVsSE9L/suNedhWhLvlaSNZy2P6Z4fm/qnFzRdxpA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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