SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '43129f261c886c4fd53d7eb80422b2ae3669315c8241343b55c523d1b98553ac' 
  AND token = 'iUjBLReNvqLECDjCaDjxMNe4wr3w0/tP/MxceN8+QmE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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