SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e82ddddc7b0e930a3af43e3092b4002f8ed16caff87b763816caaca6258ebff1' 
  AND token = 'lkkVWmwq2mhsDJM3E8fKk41/JvCgfd/z/uL6yQxpMyc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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