SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a4bd79f8ef2c5428757c2accabd14c71fb841ce96d2b817590f2af3e17ccfe04' 
  AND token = 'lpYgQu/Qj8WVG6PGDP/hAaCAS/dXuXI+vq6pFhGN/Jo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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