SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '1efbcec111c9be86845ecb66528cbe2736c1be87a4d36e6bf37933a579532334' 
  AND token = 'tYaI481kaHWr8um8/vKtwFxEqzQWX7B+nU2qTuSW8jE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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