SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1c3646302d1da929db8865f98678d82ea08f8f1f9541f5210e99dad16f756ea7' 
  AND token = 'LPdMG7qqGkYpBtv8TRvlsU98drIHcGYIncuVFGDIngs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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