SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'd644d5467356c4a9b689248ae9633472d98c026d045a48d270e98c08b0b924a1' 
  AND token = 'zs/1wpMy5WYdHGxbS0dW4qrWDdRWyfAKm5lz9NQIW64=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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