SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eaf111155c5d8ca76c14ee4972a7ce00fc9e67f376d78c84770783f8408d1297' 
  AND token = 'qjDS86gHOYL77sO3NXPlzETuXbDhfxf3m9wErTYo4UI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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