SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1dd2d014cb73f17e11e5669246fffa74d1674f2c96721872fe8cd66a8a0d4e76' 
  AND token = 'lBkfe8jrzFpBn35l0nvQrwCiYGSjusomQya5bV1Hg/A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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