SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0950b5d05ddcf35e4293109fc8272ed062a9e26496963d7db9d43ee7edb681c5' 
  AND token = '3RiKQmNgFxJUFBzK9/CzjF8/LQVp21+EuZmT5fLKSks=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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