SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '11f343c6d73c6a1147ab634c48420162ff8bfa6e82a2bf98a9b7664f309d8ad7' 
  AND token = 'N39AarW86i1iNH3MHvOOuW5SwU5deO/hp+iAdXoF3/w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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