SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b1d5286cd66784066c7a0bea7c1d90ec6d9312b5e15b16c595dd084aef04b3c3' 
  AND token = 'RXY84wWFAdoiezdCcP+N0hP1a0Ft2FX9Ok7c/OUFoeM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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