SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bb7a6865407cfadd85ead473bbc33fa0ec4c3bfb4d729315ba371e8247a4a35b' 
  AND token = 'iCMJ7G46FOghFgNcCtBl6fYfVYYboz43L18FEZT+o98=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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