SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60eba65bc28263e890c8f038e5322b4fdecda05c6f8d51d6592db3f9f70fb9a6' 
  AND token = 'kfvPHzHiSjbkfj+ThDj95bJLipg3Q5uWhAkJg1Cvb70=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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