SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0b288a912f54273342cbfa3473803e2827cfdd1344249f8d01b033d10cdd78fe' 
  AND token = 'QKfeJUtOnNwk3pFOuegCqEbL6vVjpS6TJgPTa7VezD8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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