SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac1cdc2299dad53d05464a274151bbcc6270292ab12d16a78862f25901297183' 
  AND token = 'uROqPZD0VBAFQKPlYR7CqTDv9sWgnJVTIPIOtplmz+k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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