Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'bbf4ef5879e816a30eb59b42318ccd45b2ee7a8d231ba99f5f63f4f7ba535158' 
  AND token = '3uG8Qx/JzDDUHiYa86TlShTB9kfQHF8u+D4fQsKnklQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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