SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '77a10431a6ef4a6aa922067e51befb210c92da979537427d65906020d8e69b06' 
  AND token = '+fLdUymcNBpsK0EyrSc3PQGfjgAMk1WDewbunkbHNe8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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