SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd1cd61534b7a73898734acfa3ba9569ac13315a9af39fa59a3ee04d2dfac8f74' 
  AND token = 'EZZUu5PakBoEKuylOnLt7OCeCEVmDxEIUhU/bI1uFWo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00056

JSON explain

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