SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '7272aaa22a9b719bc9c11cc492898c38e4dfde42e845792bdeafa69996c15e32' 
  AND token = 'VWNB1laGSLOwtfdDPAgw/TRnDaT1P3DM/b/15odSLAM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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