SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '68b2dfce91403639c65d751254373592d9f52bb109a6ab6ebbd7d5b9ed434f78' 
  AND token = 'wOa8vFlP+caLjiAR1zA/JyXoPu5KPuHwyUyNSepYhKc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}