SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b823526dbcaf7d9dbbb9916c07cc551f03d4298b3f05c5361060bd742ff90cf1' 
  AND token = 'IlhBbOtCj9ruek+bfkBATTDE+xQZZgXPtWUmuNuV3b8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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