SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f7c3b9998ddb193ea2041af3215479a76ea8e53e1c882c7cd82596760ba23810' 
  AND token = 'LLbtRkPp90QWJ0r+XtEwvQERPBKpy08hesUzVrgCThc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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