SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5d8834421f56ebe074e8ccada587951bb9721011d0f8a261c1616edd1b8283a9' 
  AND token = 'ACtv6b4F3kgvo2qtuf2HMiP6VKphYeK/UFOjjllCZhc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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