SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bbfc0aa97bcf62f01f484f0eb9ff843ffdda7090896e7eefae08de6e1fa98b2a' 
  AND token = 's5ozBpXqduGL76QNDejnYgGedSIkyfqP3IhdozaWvwk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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