SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8af34b967a2c5ebf10439906504090b0a02f5a8784c60c449f645ac57a521d09' 
  AND token = 'AqhXpk1h3UaJEXifZEh2reORZArhKXlY+iyEBtFKvTo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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