SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '7b1b5cc82077284e190f5141fb4d46b28c198f117b9f13043fcac964fbc1173a' 
  AND token = 'lYWRLD/w4sAFt7Ur7QMqj1N9ALvZKmhrsGo4kB7+0IA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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