SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2750acb32f4748a1732af226da93b9b3af86439465631c637a67c72f15de9e97' 
  AND token = '2PsHyjeK9tOYGLvRgIVbYbJoNTHkr2YOLf8fgYqI/SQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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