SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6f23b515c2525e9ace81ff61758b2b1ef4d962e604fd57f1b4b7eea3764985a3' 
  AND token = 'TvL3MqdK12BxKnHcDnNCxs460TQx47Qi/EGElGR8bOc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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