SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2fac862bb873ba77d083705bc346815e0e1df0bbfd79076a8e3392fa340d9bcb' 
  AND token = 'PDdA+32DuuSAkMMDUSJ+qQI2ZN8LFajz4hpTIzrdCWQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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