SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '663e0c8ac64ac13329ca03020e7efe2a9568a4282ab83880e7ebc9a1ce219c66' 
  AND token = '+k7z3a/nNclSXjgpLqOYYYowYuN+TbTZJgtN/tJ35Q8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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