SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c2d866032dc958bdf66717b3c8bae61809aff3d155ec153c8c2d5b18f3959d1a' 
  AND token = '5G8Xo2KW8wMDE3E1uvg4SP5GhVBczfufuqoQOTw0g6M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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