SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '09c04d1a8191af4d62ccf41f39f49760fa425fef588d0e274eb7caf50c7fe6d8' 
  AND token = 'SZvKzv756if1ni6jeUeAYBJUzmaBMs71CcGl7pBGNa0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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