SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5738ecd7a67dccaf0b33b9915161ed380e6fb85cf737ebaa96dfbf1466f8e733' 
  AND token = 'KOitAZJvGwrfTVPg+PrSsQTjZSn4SI0TEdoGp2ozKqY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00010

JSON explain

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