SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9236fd9d0c5d3776ec736a324a3c4efaefdb2bc94fc0ba70bc80c41a94b12fbc' 
  AND token = 'mjJMydrJLQ7UKWUwaubKSnxHPJykRq1CkN5tC8h6CCE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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