SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f46a1f7171160e8853d14280b90d418081f89cbd3745c9cb258177f6c511e408' 
  AND token = '/DaXFbm/aNsDzgFsTCraMHOCHVQkf39MpL9csWsSGsU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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