SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6c598c08b3b89f85d0c02b387243f5d6cae7843eecfb01b9cd9325ac502ef6f6' 
  AND token = '85+ykvC1lZPSEMp77Pe6/O94XOnLWkoPtVlCANsq3cI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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