SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '29ee545b4293c6ea853a17ba7b9aba038439cac7b10c8e1faaec7146641a8ebe' 
  AND token = 'ygYWODQB14WuvRLbel1tYTpM0Taf3eF8eIMnI++qYew=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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