SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '00fdbad57b35255c08867fa0f1d46acd90f154710c89375c744c42c220f3b1ff' 
  AND token = 'Lhqtgnp61Pjdr5gQsGAEATq0mJJ56MCjawKwkAUCk6s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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