SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '54efca1d5dcf46ce88135dc16035d4ab951bd77e015bb68bf91b4547ad4904d3' 
  AND token = 'Iat3yqR5TORoiG4id9zMjADihnzBYai0ui7CXdu3NSI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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