SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7cffc1e1ab85fa842d9c09840e790374b8dd99bfe6a564a2c4361b35c9f5657b' 
  AND token = '88TeaXBTWOYQnwVOXymZHC3XEbf2+xHn+dVCzXm3unw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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