SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '404bdd5f45ff6457764117076063e5a2116f5093ae1c480b59feae8db160f1b1' 
  AND token = 'UrVWqhHC6bFDBe3DjaLD/AsxYOxBRTl8AvXqstZzIqg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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