SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '44486a0cdab0acc74b9cefd7f419f1638a9d2b16137d7515bbafae04a43a1917' 
  AND token = 'OjrtWVIIgjYMUi3pYfmaigEu9AbSE9ilZCRkqtwUh1E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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