SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '34863c2bd8b0220a523b2beeb6511ef2094838bb347b75f224fb44a7f3c794a8' 
  AND token = 'L85vhMspggXjzyu/kJYcaWGW3GsfextD/pDvHDrAozs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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