SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8bafd8c330da4ca2324077b5c3ee4c5ee53d1eda8cac6cb5f3fa9e60bdf08955' 
  AND token = 'NyH0Z0iBl7Ie8kmLwjGAkTPNHvBp9QD3JxNhKyKwJGU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}