SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d67f188d5c4057ae9f36921e6d452923c58963afa81c8778bf518f005b54e49' 
  AND token = 'Y8MFRw1ofhdVlUmNUzH7+J8PWGGnpCKCt0G1Cfb9JTI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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