SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '971579e458452c7e350520b8e408642bd97d3ea9d1c233739020c1c48f433c8e' 
  AND token = 'tmhlCZoINJMju9Ao64OAkSdZPhsQWeSDJVk3BjdYxDE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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