SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ca49fcfb8759465b89e7aa5db2641aa47c5be2e9225785ae77c7d881273d3ea6' 
  AND token = 'ohMhbN3W9c9pZgc74N5WGRVGvL9ffPktQCc9ki1HGaM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}