SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '17d1d8cf9cffefa752c9e4323f90b39c45d61ea0631179a44d5cea6eeb7ddd8b' 
  AND token = 'iDhxkHvyUzWOw1+//qRRI/xwsvLg14iILQy7GhktZkE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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