SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2f39519345dc6d2c64c4fc2a32e361399a2348167cf3d6e0a77071c690f5b44d' 
  AND token = 'sbQaRHesAPmYHTyQMn1+gg2FlRjKmXpqnW+TYPRbjnc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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