SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '85bb25180e35d88317a24436e45622b231ba647cee5fbba38d53b140b0e0f5c9' 
  AND token = 'Xc5IvvlGdtyUYSQD0UQBRDcgwMeXiPVs/zeyYTZps70=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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