SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b79547bae92be900f60120b6c9f354458efc43d62b4603b7b1db73f068e1390c' 
  AND token = 'Bz1czxnx0aAtS3ncOfBat03stu+kHfd6juJZAr5Vkas=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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