SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f99488a7c3f15eab14b11a201a4caee150eac06dcdc6db90f6d01dcacfe9197c' 
  AND token = 'ir1Xf+PrfUGCrX8e8nPkRiEWYD+JADJVUeNJbCBiqGY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00009

JSON explain

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