SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e6f1b1add1801ee2a438bbaa09504c42e79061d7e80441ebfacc60bf77e25faa' 
  AND token = 'nGMOVatrQHfXzKkbeLWB7Wl6IDVdGzigDY7bX7KF16Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00158

JSON explain

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