SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a671fbb08aff9b526d8229b1917ea58ce97b0674fed1fb716a90f804503831e' 
  AND token = 'LBuxxZDsDlJZYDoIohkgjgsYGrEAZok2XQ5HAKeAVcs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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