SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd75bcf1454d5074a5e1bfbeaecccaed6d309f1834cc6f5fe4c384692d5e31158' 
  AND token = 'vIGbuSxN5FGMr8c/MzzeSQjaWAWkcgeZelFDFnAX7CI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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