SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48e190195fcc9d92783f7fe3a351fd5f9eebf41d2f40c30ad2113e48d2283444' 
  AND token = 'nOybpJurE/yshRwCgLkkdqd38kNrlyVtzFxGOEh1rkw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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