SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8af9d871b39f815e692d4cda0bb14ebc4f9160197c6db4a2a9cd7d0374c5837b' 
  AND token = 'mJWOZwHqPAamKrKhF1EKiCv95HXJVi1g5Na9lN+ayQo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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