SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e2cb5ea310efa7b700c800161d16150cd7091a879effc60e21b8d4f87cf717e' 
  AND token = 'XAlsk2bcBAuAeejeLaaoascNKuNeEgwQIgmax22OfW4=' 
  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"
    }
  }
}