SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '638b0c9075e4756f3dbff451eb54626084f48814c9a282a3955e2308bb17bcb5' 
  AND token = 'Knw5BxyXYVTyNS6WWFLH1riNzhZ5Gn+imKi/0QRa7BM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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