SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd39e79bb47972a55107c82b771864ef1f907488b908fd42cf620790d7fcecc8a' 
  AND token = 'K2sdgcb/tAcjWbXy2/Lv7VOxcyogNR3lyPhLlvkxkXk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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