SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b4109232dcafcd143d8c4b2c5d308764e86861460f6da3e0ec12456171289c79' 
  AND token = 'NELOJep1Ej0uylU9TC4MjugRVApPJUyL/JjkcmtD/Xw=' 
  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"
    }
  }
}