SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '98d4e1525880e79593781c582e3a07d0adc56bbe86bce18c86e1d871f3e584ad' 
  AND token = 'Wrxv3vdIaBXlRJ5zhydCNeEfXUKqpH24emiJOJGcNB0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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