SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '2e75a4d37f01c1b03e406bfcbf1ccb00dfbdd97573f9318adf7db4e9e449efe3' 
  AND token = 'eyOfmeJ6p/4ZTlGn2s6y8FtUnAjQxV2NgzgdoIAne2c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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