SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3dc67d487e78cf800646e50cfab33e977694ae940ea6703940d3df164ac4017f' 
  AND token = '5s76LrqCL4XlEJXaHT5A0GZD8yShbwJy1lhHKr1pX78=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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