SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c4bf759386d0e72d1562c6b94bfc841e38093c268db5b23ba4c36e636e252e8a' 
  AND token = 'DGn8DfvloV3JTv1rS044gaUCZMZYYruzju4P+ScrOZg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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