SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60c7574d6ceef5737e2ed322c8d28049f4337e253fc2fb04846609ec77f75e96' 
  AND token = 'BUhRf8JYltiFYIshGAUUZtbbiv/v3+xbkMoelTCzt90=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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