SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '4dbacd1605f65028b0a2a47723fc6d1d703538a06cb28f84eeb1288fc563895e' 
  AND token = 'uE+4CprgHtfD+98Zg6bfPP6cWvgh6L3fMbeimgcQdaI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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