SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '26d1aa63f1ecdfea0606fc638bbc66bcf6599dc447cf2f1628a70d71f87045bb' 
  AND token = 'pm4fTVf2ItfWn3QJvIWwntPampY8ScgMPkJiUtCuRnA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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