SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a731ad2fd57d13ccb366ab099002d202aa6a532bc6c731cf3f4b858dd7e5b57' 
  AND token = 'N92Blt/YQLNHpz+C157SmptEmacIiQF9yMMJBWsbLnk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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