SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1b789ce58044fac6af26025e98c5d3535f615990ecbdf9a1e9559f48a61d8416' 
  AND token = 'LA+FGuZj0ZBC96jD3vlPnH6gO7eqI/T9NhD+4atkPps=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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