SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6944ae2e99254f091d073b337f12809f6156214744e8a47900bd4ccb5127f36b' 
  AND token = 'N34nG3ZQfpYXV+pde0lEkvHKxjjgcstBws9zsilfUAA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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