SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6602c5bc9d350a093534715c52fe5a897d806c04ebab0faf11cc81217ecc1896' 
  AND token = 'jphe/iF+jEWb1zoyPh7dSbWXv6RcimPCika1Ju35Q/U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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